CAFO and Biodigesters Fact Sheet — Sustain Rural Wisconsin Network

Journal Articles

1. Alarcón, L.V., Allepuz, A. & Mateu, E. Biosecurity in pig farms: a review. Porc Health Manag 7, 5 (2021).

Link: https://doi.org/10.1186/s40813-020-00181-z

The perception of the importance of animal health and its relationship with biosecurity has increased in recent years with the emergence and re-emergence of several diseases difficult to control. This is particularly evident in the case of pig farming as shown by the recent episodes of African swine fever or porcine epidemic diarrhea. Moreover, a better biosecurity may help to improve productivity and may contribute to reducing the use of antibiotics. Biosecurity can be defined as the application of measures aimed to reduce the probability of the introduction (external biosecurity) and further spread of pathogens within the farm (internal biosecurity).

Thus, the key idea is to avoid transmission, either between farms or within the farm. This implies knowledge of the epidemiology of the diseases to be avoided that is not always available, but since ways of transmission of pathogens are limited to a few, it is possible to implement effective actions even with some gaps in our knowledge on a given disease. The development of quantitative assessment methods will permit a more precise selection of measures and a fine evaluation of their impact. Collaboration with other branches of science such as sociology or psychology may help to the sustainable implementation of biosecurity plans.

2. Almond, G. Water: Optimizing Performance While Reducing Waste. 46th Annual North Carolina Pork Conference North Carolina State University, 2002.

Link: Water: Optimizing Performance (ncsu.edu)

Due to the relative abundance of water and its “low price”, there previously was little demand for research on the role of water and water delivery systems in US pork production, and specifically with applications to North Carolina. Water is important in pork production for two general reasons: its role in pig performance and its contribution to waste.

3. American Academy of Pediatrics. Committee on Environmental Health and Committee on Infectious Diseases, 2009. Drinking water from private wells and risks to children. Pediatrics 123(6):1599– 1605.

Link: Drinking Water From Private Wells and Risks to Children (aappublications.org)

Drinking water for approximately one sixth of US households is obtained from private wells. These wells can become contaminated by pollutant chemicals or pathogenic organisms and cause illness. Although the US Environmental Protection Agency and all states offer guidance for construction, maintenance, and testing of private wells, there is little regulation. This policy statement provides recommendations for inspection, testing, and remediation for wells providing drinking water for children.

4. American Association of Swine Veterinarians. Holding Time Calculations for Feed Ingredients to Mitigate Virus Transmission. February 4, 2020

Link: Holding-Time-Calculations-for-Feed-Ingredients-to-Mitigate-Virus-Transmission

Imported feedstuffs are not all manufactured and handled in the same way. Consideration should be given to the conditions of manufacture and how these products are handled and transported. Feedstuffs that are manufactured, sealed, handled and shipped under biosecure conditions that produce a product free of pathogens and prevents post-processing contamination are not a risk to animal health. If a feedstuff is not produced under biosecure conditions, is produced under unknown conditions or is not sealed to prevent post-processing contamination, a holding time gives an opportunity for viral contaminants to naturally degrade and to not be infectious.

5. American Association of Swine Veterinarians. On-Farm Euthanasia of Swine. 2016 #04970-11/16 Link: 2016EuthRec-EN.pdf (aasv.org)

Euthanasia is the humane process whereby the pig is rendered insensible, with minimal pain and distress, until death. For the euthanasia process or method to be considered humane, it must be quick, effective and reliable. Key elements for determining if a method is humane include: • minimal pain and distress to the pig during administration, • rapid loss of consciousness, • death is achieved quickly and consistently. This brochure provides practical recommendations for the on-farm euthanasia of swine. It also highlights euthanasia methods that have been shown to meet the definition for humane euthanasia based on the available scientific literature. However, this list may not be all-inclusive. Other options may be used as long as they meet the definition and key elements for euthanasia discussed above.

6. American Association of Swine Veterinarians. Swine Disease Manual - Porcine Reproductive and Respiratory Syndrome

Link: Porcine Reproductive and Respiratory Syndrome (PRRS)

In some operations, it may be economically feasible to depopulate, clean and disinfect the facilities and, after a few weeks, repopulate with stock free of PRRS and other major diseases. Herd closure for at least 200 days has also been used as another means to stabilize a breeding herd without depopulating. Most breeding stock companies today provide PRRS-free seed stock which was once a major limitation. Before embarking on this strategy, one should honestly assess risk factors for re-infection of the herd as well as the level of biosecurity that can be maintained by the producer. Herds located in swine-dense areas are at great risk for re-infection.

7. American Public Health Association. Precautionary Moratorium on New and Expanding Concentrated Animal Feeding Operations. November 5, 2019. Policy Number: 20194 Link: Precautionary Moratorium on New and Expanding CAFOs (apha.org)

These operations function with the high throughput and rapid turnover of an industrialized system. The enormous accumulation of manure and other untreated waste is often stored and disposed of in a manner that pollutes the air, surface, and groundwater, posing risks to the environment and human health, particularly for CAFO workers and nearby residents. This policy statement calls for a moratorium on the establishment of new CAFOs and expansion of existing CAFOs until regulation and enforcement conditions are in place to adequately protect the public’s health.

8. Arora, K. General Guidelines on Composting of HPAI Infected Carcasses. Iowa State Extension Store. July 2017.

Link: General Guidelines on Composting of HPAI Infected Carcasses (iastate.edu)

Containment of highly pathogenic avian influenza (HPAI) is a critical step which must be properly performed to ensure human and animal safety. This publication discusses how to prepare to contain a potential outbreak and what should be done to safely contain it.

9. Baykov B, Stoyanov M. Microbial air pollution caused by intensive broiler chicken breeding. FEMS Microbiol Ecol. 1999;29(4):389-392.

Link: https://academic.oup.com/femsec/article/29/4/389/527380

This study examined the extent of microbial atmospheric pollution caused by industrial broiler breeding operations and found that as birds aged, microbial numbers increased in the indoor air and were spread into the environment to a greater degree. The study also found that microorganisms could be spread by air flow up to 3000 meters from the production buildings.

10. Brender JD, Weyer PJ, Romitti PA, et al. Prenatal nitrate intake from drinking water and selected birth defects in offspring of participants in the national birth defects prevention study. Environ Health Perspect. 2013;121(9):1083-1089.

Link: https://www.ncbi.nlm.nih.gov/pubmed/23771435

The relationship between prenatal exposure to nitrates in drinking water and birth defects was examined in this study. The study concluded that higher maternal water nitrate consumption was associated with birth defects, including spina bifida, limb deficiency, cleft palate, and cleft lip.

11. Broom, DM. (2003) Causes of Poor Welfare in Large Animals During Transport. Veterinary research communications, 27 Suppl 1, 515–518.

Link: Causes of poor welfare in animal transport (nih.gov)

The welfare of animals during transport should be assessed using a range of behavioral, physiological and carcass quality measures. In addition, health is an important part of welfare so the extent of any disease, injury or mortality resulting from, or exacerbated by, transport should be measured. Many of the indicators are measures of stress in that they involve long-term adverse effects on the individual. Key factors affecting the welfare of animals during handling and transport which are discussed are: attitudes to animals and the need for training of staff; methods of payment of staff; laws and retailers' codes; genetics, especially selection for high productivity; rearing conditions and experience; the mixing of animals from different social groups; handling procedures: driving methods; stocking density; increased susceptibility to disease and increased spread of disease.

12. Brumm, M. Patterns of Drinking Use in Pork Production Facilities. (2006) Nebraska Swine Reports. 221.

Link: Patterns of Drinking Water Use in Pork Production Facilities

The amount of drinking water needed daily by the pig depends on numerous influences, including temperature, diet, stage of production and health. Daily drinking water needs for pigs range from less than 0.5 gal/pig/day for newly weaned pigs to greater than 1.5 gal/pig/day for grow-finish pigs. Water requirements for breeding swine range from 3 to 4 gal/day for gestating females and 6 gal/day for lactating swine.

13. Burgos J, Ellington B, Varela M. Presence of multidrug-resistant enteric bacteria in dairy farm topsoil. J Dairy Sci. 2005;88(4):1391-1398.

Link: https://www.ncbi.nlm.nih.gov/pubmed/15778307

In addition to human and veterinary medicine, antibiotics are extensively used in agricultural settings, such as for treatment of infections, growth enhancement, and prophylaxis in food animals, leading to selection of drug and multidrug-resistant bacteria. To help circumvent the problem of bacterial antibiotic resistance, it is first necessary to understand the scope of the problem. However, it is not fully understood how widespread antibiotic-resistant bacteria are in agricultural settings. The lack of such surveillance data is especially evident in dairy farm environments, such as soil. It is also unknown to what extent various physiological modulators, such as salicylate, a component of aspirin and known model modulator of multiple antibiotic resistance (mar) genes, influence bacterial multi-drug resistance. We isolated and identified enteric soil bacteria from local dairy farms within Roosevelt County, NM, determined the resistance profiles to antibiotics associated with mar, such as chloramphenicol, nalidixic acid, penicillin G, and tetracycline. We then purified and characterized plasmid DNA and detected mar phenotypic activity. The minimal inhibitory concentrations (MIC) of antibiotics for the isolates ranged from 6 to >50 microg/mL for chloramphenicol, 2 to 8 microg/mL for nalidixic acid, 25 to >300 microg/mL for penicillin G, and 1 to >80 microg/mL for tetracycline. On the other hand, many of the isolates had significantly enhanced MIC for the same antibiotics in the presence of 5 mM salicylate. Plasmid DNA extracted from 12 randomly chosen isolates ranged in size from 6 to 12.5 kb and, in several cases, conferred resistance to chloramphenicol and penicillin G. It is concluded that enteric bacteria from dairy farm topsoil are multidrug resistant and harbor antibiotic-resistance plasmids. A role for dairy topsoil in zoonoses is suggested, implicating this environment as a reservoir for development of bacterial resistance against clinically relevant antibiotics.

14. Burkholder J, Libra B, Weyer P, et al. Impacts of waste from concentrated animal feeding operations on water quality. Environ Health Perspect. 2007:308-312.

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/F'MC1817674/

This work-group, part of the Conference on Environmental Health Impacts of Concentrated Animal Feeding Operations: Anticipating Hazards—Searching for Solutions, found that current and generally accepted livestock waste management practices do not protect water resources from the pathogens, pharmaceuticals and excessive nutrients found in animal waste. As concern about the potential human and environmental health impact of long-term exposure to contaminated water grows, there is greater need for rigorous monitoring of CAFOs, improved understanding of the major toxicants affecting human and environmental health, and a system to enforce these practices.

15. Cambra-Lopez M, Aarnink AJ, Zhao Y, Calvet S, Tones AG. Airborne particulate matter from livestock production systems: A review of an air pollution problem. Environmental Pollution. 2010;158(1):1-17.

Link: https://www.ncbi.nlm.nih.gov/pubmed/19656601

This paper reviews research on particulate matter inside and emitted from livestock production system and reports that livestock housing is an important source of particulate matter emissions. The paper recommends additional research to characterize and control particulate matter in livestock houses, as high concentrations such as those found in livestock houses can threaten the environment and the health and welfare of humans and animals.

16. Carmichael WW. Health effects of toxin-producing cyanobacteria: "The CyanoHABs". Human and Ecological Risk Assessment: An International Journal. 2001;7(5):1393-1407.

Link: http://www.tandfonline.com/doi/abs/10.1080/20018091095087

Current understandings of cyanobacteria toxin poisonings (CTPs) and their risk to human health were reviewed in this paper. CTPs occur in fresh and brackish waters throughout the world as a result of eutrophication and climate change. Cyanobacteria toxins are responsible for acute lethal, acute, chronic and sub-chronic poisonings of wild and domestic animals and humans. These poisonings result in respiratory and allergic reactions, gastrointestinal disturbances, acute hepatotoxicosis and peracute neurotoxicosis.

17. Casey JA, Curriero FC, Cosgrove SE, Nachman KE, Schwartz BS. High-density livestock operations, crop field application of manure, and risk of community-associated methicillin-resistant Staphylococcus aureus infection in Pennsylvania. JAMA Internal Medicine. 2013;173(21):1980- 1990.

Link: https://www .ncbi .nlm .nih .gov/pubmed/24043228

Nearly 80% of antibiotics in the United States are sold for use in livestock feeds. The manure produced by these animals contains antibiotic-resistant bacteria, resistance genes, and antibiotics and is subsequently applied to crop fields, where it may put community members at risk for antibiotic-resistant infections. The objective of this study was to assess the association between individual exposure to swine and dairy/veal industrial agriculture and risk of methicillin-resistant Staphylococcus aureus (MRSA) infection. This study was a population-based, nested case-control study of primary care patients from a single health care system in Pennsylvania from 2005 to 2010. Incident MRSA cases were identified using electronic health records, classified as community- associated MRSA or health care—associated MRSA, and frequency matched to randomly selected controls and patients with skin and soft-tissue infection. Nutrient management plans were used to create 2 exposure variables: seasonal crop field manure application and number of livestock animals at the operation. In a sub-study, we collected 200 isolates from patients stratified by location of diagnosis and proximity to livestock operations. The study measured community-associated MRSA, health care—associated MRSA, and skin and soft-tissue infection status (with no history of MRSA) compared with controls. From a total population of 446,480 patients, 1,539 community-associated MRSA, 1335 health care-associated MRSA, 2895 skin and soft-tissue infection cases, and 2914 controls were included. After adjustment for MRSA risk factors, the highest quartile of swine crop field exposure was significantly associated with community-associated MRSA, health care- associated MRSA, and skin and soft-tissue infection case status (adjusted odds ratios, 1.38 [95% CI, 1.13-1.69], 1.30 [95% CI, 1.05-1.61], and 1.37 [95% CI, 1.18-1.60], respectively); and there was a trend of increasing odds across quartiles for each outcome (P ≤ .01 for trend in all comparisons). There were similar but weaker associations of swine operations with community- associated MRSA and skin and soft-tissue infection. Molecular testing of 200 isolates identified 31 unique spa types, none of which corresponded to CC398 (clonal complex 398), but some have been previously found in swine. Proximity to swine manure application to crop fields and livestock operations each was associated with MRSA and skin and soft-tissue infection. These findings contribute to the growing concern about the potential public health impacts of high-density livestock production.

18. Center for Food Security and Public Health, Iowa State University. Prepare for animal disease threats.

Link: CFSPH - Center for Food Security and Public Health (iastate.edu)

African Swine Fever was confirmed for the first time in recent years in samples from pigs in the Dominican Republic on July 28. Keeping this transboundary disease out is key.

19. Centro del los Derechos Del Migrante. Recruitment Revealed: Fundamental Flaws in the H-2 Temporary Worker Program and Recommendations for Change.

2018 Link: Recruitment_Revealed

This report reveals the reality of international labor recruitment for low-wage, temporary jobs in the United States, examining recruitment in Mexico, home to the largest number of temporary migrants who labor under H-2 visas in the U.S. The findings are based on data gathered by Centro de los Derechos Migrante through a groundbreaking survey and lengthy interviews of hundreds of H-2 workers.

20. Chambers, PG, Grandin, T, et.al. Guidelines for humane handling, transport, and slaughter of livestock. Food and Agriculture Organization of the United Nations Regional Office for Asia and the Pacific. RAP Publication 2001/4

Link: https://www.fao.org/3/x6909e/x6909e.pdf

Guidelines with several specifics on handling, design of pens and chutes, and good animal welfare standards.

21. Chen, C-T, Crespi, et. al. Long-run impacts of trade shocks and export competitiveness: Evidence from the U.S. BSE event. Agricultural Economics. 2020; 51: 941– 957.

Link: https://doi.org/10.1111/agec.12602

Examines how comparative advantages of major beef exporters changed following the 2003 bovine spongiform encephalopathy (BSE) outbreak, which significantly disrupted the U.S. beef trade until approximately 2007. Using longitudinal data on beef export values and constructed revealed comparative advantage measures, we show that while some measures of the long-run impacts of BSE on U.S. beef export competitiveness have returned to pre-2003 levels, the U.S.’s comparative advantage has not. Long-term trade competitiveness may not simply return to normal even after a short-term disruption.

22. Chiu H, Tsai S, Yang C. Nitrate in drinking water and risk of death from bladder cancer: An ecological case-control study in Taiwan. Journal of Toxicology and Environmental Health, Part A. 2007;70(12):1000-1004.

Link: https://www.ncbi.nlm.nih.gov/pubmed/17497410

The association between bladder cancer mortality and nitrate exposure from Taiwan drinking water was investigated in this study. The results showed a significant positive relationship between the levels of nitrates in the drinking water and the risk of death from bladder cancer, indicating that environmental exposure to nitrates plays a role in the development of bladder cancer.

23. Coffey, Brian et al., The Economic Impact of BSE on the U.S. Beef Industry: Product Value Losses, Regulatory Costs, and Consumer Reactions, Kansas State University, April 2000 Link: Economic Impact of BSE

As BSE spread outside Europe to Japan and, in mid-2003, to Canada, USDA enhanced its surveillance efforts and increased funding for BSE related research. Regulatory efforts to counter the disease were further strengthened when, on December 23, 2003, it was reported that a dairy cow in Washington state had tested positive. Within days of the announcement, 53 countries banned imports of U.S. cattle and beef products. In 2003, U.S. beef exports were valued at $3.95 billion and accounted for 9.6 percent of U.S. commercial beef production. The import bans caused U.S. beef exports to plummet and exports for the year declined 82 percent below 2003’s level.

24. Costa, T, Akdeniz, N. A review of the animal disease outbreaks and biosecure animal mortality composting systems. Waste Management, Volume 90, 2019, Pages 121-131,

Link: https://doi.org/10.1016/j.wasman.2019.04.047

Despite the development of new vaccines and the application of rigorous biosecurity measures, animal diseases pose a continuing threat to animal health, food safety, national economy, and the environment. Intense livestock production, increased travel, and changing climate have increased the risk of catastrophic animal losses due to infectious diseases. In the event of an outbreak, it is essential to properly manage the infected animals to prevent the spread of diseases. The most common disposal methods used during a disease outbreak include burial, landfilling, incineration and composting. Biosecurity, transportation logistics, public perception, and environmental concerns limit the use of some of these methods. During a disease outbreak, the large number of mortalities often exceeds the capacity of local rendering plants and landfills. Transporting mortalities to disposal and incineration facilities outside the production operation introduces biosecurity risks. Burying mortalities is limited by the size and availability of suitable sites and it has the risk of pathogen survival and contamination of groundwater and soil. Portable incinerators are expensive and have the potential to aerosolize infectious particles. Composting, on the other hand, has been recognized as a biosecure disposal method. Although composting has been shown to eliminate HPAI, FMD, PED, and PRRS viruses, no studies have been reported regarding African swine fever. More studies are needed to show the biosecurity of composting in eliminating infectious diseases and especially microbial DNA, which is often referred to be the reason for reoccurring diseases.

25. Costa, D. Employers increase their profits and put downward pressure on wages and labor standards by exploiting migrant workers. Economic Policy Institute, Aug 27, 2019.

Link: Employers and Migrant Workers

Our current immigration system isn’t working for workers. Instead, it benefits low-road employers who exploit the immigration status of unauthorized immigrants and authorized guestworkers through a legal framework that puts downward pressure on wages and leaves migrant workers powerless to enforce their labor rights and hold employers accountable. This hurts both migrants and the U.S. workers—citizens and lawful permanent residents—who work alongside them. Congress needs to reform the U.S. immigration system by granting lawful permanent resident status to the current unauthorized immigrant population; revising temporary work visa program rules; enacting new protections from retaliation for migrant workers; appropriating more funding for labor standards enforcement; and permanently banning employers from hiring through temporary work visa programs if they have violated immigration or labor laws.

26. Cullens, F. Water Use on Dairy Farms. Michigan State University Extension. October 18, 2011. Link: Water use on dairy farms - MSU Extension

A reliable, high quality water supply is essential to dairy farms. Water is used for animal consumption, milk cooling, cleaning and sanitizing equipment, cow cooling, irrigating crops, producing value added products, moving manure and cleaning the barns via flush systems.

27. Dee SA, Deen J. Evaluation of an industry-based sanitation protocol for transport vehicles contaminated with porcine reproductive and respiratory syndrome virus. J Swine Health Prod. 2006;14(3):126-132.

Link: Evaluation of an industry-based sanitation protocol

Contaminated livestock trailers certainly represent a significant risk for movement of the virus between and within herds. Historically, this disease risk has been effectively mitigated in some cases with the use of trailer washing, disinfection protocols, and thermo-assisted drying and decontamination (TADD) systems. This paper summarizes four studies that evaluated individual aspects of trailer sanitation programs including TADD and multiple disinfectants alone, as well several protocols that include washing, disinfection and TADD. To test a protocol, using conditions found on commercial swine production units, for sanitation of 1:150 scale models of commercial transport vehicles contaminated with porcine reproductive and respiratory syndrome virus (PRRSV). High-pressure washing of transport trailers, followed by 90 to 120 minutes exposure to either modified potassium monopersulfate or quaternary ammonium chloride disinfectants applied with a hydrofoamer is likely to eliminate residual infectious PRRSV.

28. Dee, SA, Bauermann, FV, Niederwerder, et. al (2018). Survival of viral pathogens in animal feed ingredients under transboundary shipping models. PloS one, 13(3), e0194509.

Link: https://doi.org/10.1371/journal.pone.0194509

The goal of this study was to evaluate survival of important viral pathogens of livestock in animal feed ingredients imported daily into the United States under simulated transboundary conditions. Eleven viruses were selected based on global significance and impact to the livestock industry, including Foot and Mouth Disease Virus (FMDV), Classical Swine Fever Virus (CSFV) and African Swine Fever Virus (ASFV). Surrogate viruses with similar genetic and physical properties were used for 6 viruses. Results support published data on transboundary risk of PEDV in feed, demonstrate survival of certain viruses in specific feed ingredients ("high-risk combinations") under conditions simulating transport between continents and provide further evidence that contaminated feed ingredients may represent a risk for transport of pathogens at domestic and global levels.

29. Deschuyffeleer, T. P., Tyberghien, L. F., Dickx, V. L., Geens, T., Saelen, J. M., Vanrompay, D. C., & Braeckman, L. A. (2012). Risk assessment and management of Chlamydia psittaci in poultry processing plants. The Annals of occupational hygiene, 56(3), 340–349.

Link: https://doi.org/10.1093/annhyg/mer102

Chlamydia psittaci causes respiratory disease in poultry and can be transmitted to humans. Historical outbreaks of psittacosis in poultry workers indicated the need for higher awareness and an efficient risk assessment and management. This group reviewed relevant previous research, practical guidelines, and European directives. Subsequently, basic suggestions were made on how to assess and manage the risk of psittacosis in poultry processing plants based on a classical four- step approach. Collective and personal protective measures as well as the role of occupational medicine are described. Despite the finding that exposure is found in every branch, abattoir workstations seem to be associated with the highest prevalence of psittacosis. Complete eradication is difficult to achieve. Ventilation, cleaning, hand hygiene, and personal protective equipment are the most important protective measures to limit and control exposure to C. psittaci. Adequate information, communication, and health surveillance belong to the responsibilities of the occupational physician. Future challenges lay in the rigorous reporting of infections in both poultry and poultry workers and in the development of an avian and human vaccine.

30. Donham KJ, Wing S, Osterberg D, et al. Community health and socioeconomic issues surrounding concentrated animal feeding operations. Environ Health Perspect. 2007:317-320.

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1817697/

The Workgroup on Community and Socioeconomic Issues examined the impacts of CAFOs on the health of rural communities, using the World Health Organization's definition of health, "a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity." The workgroup recommended more stringent CAFO permitting, limiting animal density per watershed, improving local control, mandating environmental impact statements and considering bonding for manure storage basins.

31. Dyal JW, Grant MP, Broadwater K, et al. COVID-19 Among Workers in Meat and Poultry Processing Facilities ― 19 States, April 2020. MMWR Morb Mortal Wkly Rep 2020:557-561 Link: COVID-19 Among Workers in Meat and Poultry Processing Facilities (cdc.gov)

Congregate work and residential locations are at increased risk for infectious disease transmission including respiratory illness outbreaks. SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is primarily spread person to person through respiratory droplets. Nationwide, the meat and poultry processing industry, an essential component of the U.S. food infrastructure, employs approximately 500,000 persons, many of whom work in proximity to other workers (1).

Because of reports of initial cases of COVID-19, in some meat processing facilities, states were asked to provide aggregated data concerning the number of meat and poultry processing facilities affected by COVID-19 and the number of workers with COVID-19 in these facilities, including COVID-19–related deaths. Qualitative data gathered by CDC during on-site and remote assessments were analyzed and summarized. During April 9–27, aggregate data on COVID-19 cases among 115 meat or poultry processing facilities in 19 states were reported to CDC.

32. Eastridge, M. Water Usage on Dairy Farms. Buckeye Dairy News Ohio State University Extension Volume 8 Issue 1.

Link: Water Usage on Dairy Farms (osu.edu)

As we always say "water is the most important nutrient", but all too often it is the most ignored nutrient when we are thinking of nutrition and animal performance. Therefore, we must constantly monitor water quality and quantity on dairy farms for animal health and performance and for protecting the environment.

33. Filice GA, Nyman JA, Lexau C, et al. Excess costs and utilization associated with methicillin resistance for patients with Staphylococcus aureus infection. Infection Control & Hospital Epidemiology. 2010;31(04):365-373.

Link: https://www.ncbi.nlm.nih.gov/pubmed/20184420

Healthcare costs of methicillin-resistant S. aureus (MRSA) infections and methicillin-susceptible S. aureus (MSSA) were compared in this study. MRSA infections were found to be independently associated with higher costs, more comorbidities, and higher likelihood of death than MSSA infections.

34. Foltz JD, Jackson-Smith D, Chen L. Do purchasing patterns differ between large and small dairy farms? Econometric evidence from three Wisconsin communities. Agric Resour Econ. Rev. 2002;31(1):28–38

Link: Do Purchasing Patterns Differ Between Large and Small Dairy Farms? (umn.edu)

Using farm data from three dairy-dependent communities in Wisconsin, this study addresses the question: Do small farms spend more locally than large farms? The work develops a theoretical model of farm cost functions with transaction costs varying between local and distant input sources. This model is then tested econometrically, describing farm costs and where they were spent as a function of transaction/search costs and farm characteristics. The results suggest that scale does matter to farm spending patterns.

35. Fox, M. A., et. al. (2016). Meeting the public health challenge of protecting private wells: Proceedings and recommendations from an expert panel workshop. Science of the Total Environment, 554-555, 113-118.

Link: https://doi.org/10.1016/j.scitotenv.2016.02.128

Private wells serving fewer than 25 people are federally unregulated, and their users may be exposed to naturally occurring agents of concern. This panel assessed current conditions of ground water as a source for private wells, identified emerging threats, critical gaps in knowledge, and public health needs, and recommended strategies to guide future activities to ensure the safety of private drinking water wells.

36. Fry JP, Laestadius LI, Grechis C, Nachman KE, Neff RA. Investigating the role of state permitting and agriculture agencies in addressing public health concerns related to industrial food animal production. PloS one. 2014;9(2):e89870.

Link: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0089870

This study explored how state permitting and agriculture agencies respond to environmental public health concerns regarding industrial food animal production through qualitative interviews with state agency staff in seven states. The study found that the agencies were unable to adequately address these environmental public health concerns due to narrow regulations, limited resources and a lack of public health expertise. When these constraints are considered alongside those faced by health departments, significant gaps in the ability to respond to and prevent public health concerns and issues are revealed.

37. Gomes A, Quinteiro-Filho W, Ribeiro A, et al. Overcrowding stress decreases macrophage activity and increases Salmonella enteritidis invasion in broiler chickens. Avian Pathol. 2014;43(1):82-90. Link: https://www.ncbi.nlm.nih.gov/pubmed/24350836

This study sought to characterize the immunosuppressive effect of overcrowding stress in broiler chickens. Overcrowding was found to compromise the intestinal immune barrier and integrity of the small intestine, resulting in inflammation and decreased nutrient absorption. The study concludes that animal welfare measures and avoiding overcrowding stress factors in maintaining poultry health and decreased susceptibility to Salmonella infection.

38. Graham JP, Leibler JH, Price LB, Otte JM, Pfeiffer DU, Tiensin T, et al. The animal-human interface and infectious disease in industrial food animal production: rethinking biosecurity and biocontainment. Public Health Rep. 2008;123(3):282-99.

Link: https://www.ncbi.nlm.nih.gov/pubmed/19006971

Understanding interactions between animals and humans is critical in preventing outbreaks of zoonotic disease. This is particularly important for avian influenza. Food animal production has been transformed since the 1918 influenza pandemic. Poultry and swine production have changed from small-scale methods to industrial-scale operations. There is substantial evidence of pathogen movement between and among these industrial facilities, release to the external environment, and exposure to farm workers, which challenges the assumption that modern poultry production is more biosecure and biocontained as compared with backyard or small holder operations in preventing introduction and release of pathogens. An analysis of data from the Thai government investigation in 2004 indicates that the odds of H5N1 outbreaks and infections were significantly higher in large-scale commercial poultry operations as compared with backyard flocks. These data suggest that successful strategies to prevent or mitigate the emergence of pandemic avian influenza must consider risk factors specific to modern industrialized food animal production.

39. Graham JP, Evans SL, Price LB, Silbergeld EK. Fate of antimicrobial-resistant enterococci and staphylococci and resistance determinants in stored poultry litter. Environ Res. 2009;109(6):682-689.

Link: https://www .ncbi.nlm.nih .gov/pubmed/19541298

This study examined the survival of anti-microbial resistant enterococci and staphylococci and resistance genes in poultry litter to better understand how land application of poultry litter can affect the surrounding population's environment. The study found that poultry litter storage practices do not eliminate drug-resistant bacterial strains, thus allowing the spread of these drug-resistant pathogens into and through the environment via land application of poultry litter.

40. Graham JP, Price LB, Evans SL, Graczyk TK, Silbergeld EK. Antibiotic resistant enterococci and staphylococci isolated from flies collected near confined poultry feeding operations. Sci Total Environ. 2009;407(8):2701-2710.

Link: https://www.ncbi.nlm.nih.gov/pubmed/19157515

This study examined if and how antibiotic resistant bacteria are transferred from poultry operations to nearby communities, and found that flies caught near poultry operations carried the same drug-resistant pathogens as those found in poultry litter. The study concludes that flies may be an important vector in the spread of drug resistant bacteria from poultry operations and may increase human exposure to these resistant pathogens.

41. Graham JP, Nachman KE. Managing waste from confined animal feeding operations in the United States: The need for sanitary reform. Journal of Water and Health. 2010;8(4):646-670.

Link: https://www.ncbi.nlm.nih.gov/pubmed/20705978

Trends affecting food animal waste production, risks associated with food-animal wastes, and differences between food-animal waste and human biosolid management practices were examined in this study. The study found that no standards exist for the 335 million tons of food animal waste applied to land in the US, while human biosolids, which make up just 1% of all land-applied wastes, are subject to standards. Hormones, arsenicals, high nutrient loads, antibiotics, and pathogens, including antibiotic-resistant pathogens, are often present in animal waste. The authors made recommendations for improving management of food-animal waste through existing and new policies.

42. Guberti, V., Khomenko, S., Masiulis, M. & Kerba S. 2019. African swine fever in wild boar ecology and biosecurity. FAO Animal Production and Health Manual No. 22. Rome, FAO, OIE and EC.

Link: en-manual-asfinwildboar-2019-web.pdf (oie.int)

African swine fever (ASF) is a devastating hemorrhagic viral disease of pigs, affecting domestic and wild pigs of all ages and sexes. The disease is the cause of major economic losses, threatens food security and safe trade, and challenges sustained swine production in affected countries. Since ASF emergence in Georgia in 2007, the disease has spread to many countries in Europe and in 2018 was detected in East Asia, where over 60 percent of global domestic pig inventories are found.

43. Gulis G, Czompolyova M, Cerhan JR. An ecologic study of nitrate in municipal drinking water and cancer incidence in Trnava district, Slovakia. Environ Res. 2002;88(3):182-187.

Link: https://www.ncbi.nlm.nih.gov/pubmed/12051796

This ecologic study was conducted to assess the association between nitrate levels in drinking water with non-Hodgkin lymphoma and cancers of the digestive and urinary tracts in an agricultural district. The study found is that a higher incidence of some cancers was associated with higher levels of nitrate in drinking water. The trend was found in women for overall cancer cases, stomach cancer, colorectal cancer and non-Hodgkin lymphoma, and in men for non- Hodgkin lymphoma and colorectal cancer.

44. Guthrie, T. Water Needs of Pigs. Michigan State Extension. May 2011 Link: Water needs of pigs - MSU Extension

How much water do pigs need? Pigs lose water through four routes: kidneys (urination), intestines (defecation), lungs (respiration) and some through evaporation (skin- sweat glands are largely dormant).

45. Harmon, J. Drip Cooling for Sows in Farrowing House. Iowa State Extension Store. October 2008 Link: Drip Cooling of Sows in Farrowing House (iastate.edu)

Research indicates that summer heat stress on sows can be reduced by using a system that continually drips water on the sow's shoulder in hot weather.

46. Heaney CD, et. al. Source tracking swine fecal waste in surface water proximal to swine concentrated animal feeding operations. Sci Total Environ. 2015;511:676-683.

Link: http://www.sciencedirect.com/science/article/pii/S0048969714017641

The microbial quality of surface water proximal to swine CAFOs was investigated in this study to better understand the impact of CAFOs on the surrounding environment. The results demonstrate overall poor water quality in areas with a high density of swine CAFOs, with high fecal indicator bacteria concentrations in waters both up- and down-stream of CAFO lagoon waste land application sites. The swine-specific microbial source tracking markers used in the study were also shown to be useful for tracking off-site conveyance of swine fecal wastes and during rain events.

47. Heederik D, Sigsgaard T, Thorne PS, et al. Health effects of airborne exposures from concentrated animal feeding operations. Environ Health Perspect. 2007:298-302.

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1817709/

This report from a Conference on Environmental Health Impacts of Concentrated Animal Feeding Operations: Anticipating Hazards —Searching for Solutions working group states that toxic gases, vapors and particles are emitted from CAFOs into the general environment, and that while these agents are known to be harmful to human health, there are few studies that explore the health risks of exposure to these agents for the people living near CAFOs. While there is evidence that psychophysiologic changes may result from exposure to malodors and that microbial exposures are related to deleterious respiratory health effects, the working group concluded that there is great need to study and evaluate the health effects of community exposure to these CAFO related air pollutants to better understand the impact of CAFOs on the health of community members and farm workers.

48. Heisler J, Glibert PM, Burkholder JM, et al. Eutrophication and harmful algal blooms: A scientific consensus. Harmful Algae. 2008;8(1):3-13.

Link: http://www.sciencedirect.com/science/article/pii/S1568988308001066

The US EPA held a roundtable discussion to develop consensus among academic, federal and state agency representatives on the relationship between eutrophication and harmful algal blooms. Seven statements were adopted during the session, which include acknowledgement of the important role of nutrient pollution and degraded water quality in the development and persistence of many harmful algal blooms.

49. Horton RA, Wing S, Marshall SW, Brownley KA. Malodor as a trigger of stress and negative mood in neighbors of industrial hog operations. Am J Public Health. 2009;99(S3):S610-S615.

Link: https://www.ncbi.nlm.nih.gov/pubmed/19890165

The association between malodor and air pollutants from nearby hog CAFOs and reported stress and negative mood was evaluated in this study to better understand the role of CAFOs in human health. The study found that malodor and air pollutants acted as environmental stressors and triggers of negative mood and recommended their inclusion in studies of the health impacts of environmental injustice.

50. Hribar C, Schultz M. Understanding concentrated animal feeding operations and their impact on communities. Bowling Green, OH: National Association of Local Boards of Health. 2010. Link: https://www.cdc.gov/nceh/ehs/docs/understanding_cafos_nalboh.pdf

The National Association of Local Boards of Health produced this report with the support of the Centers for Disease Control and Prevention and the National Center for Environmental Health to assist local board of health members better understand their role in mitigating potential issues with CAFOs. The report concludes that large-scale industrial food animal production can cause numerous public health and environmental problems and should thus be monitored to prevent harm to surrounding communities. Suggested actions include passing ordinances and regulations, and increasing water and air quality monitoring and testing. The report also concludes that local boards of health, in collaboration with state and local agencies, are an appropriate body for instituting these actions due to the local nature of CAFO concerns and risks.

51. Hseu Z-Y, Chen Z-S. Experiences of Mass Pig Carcass Disposal Related to Groundwater Quality Monitoring in Taiwan. Sustainability. 2017; 9(1):46.

Link: https://doi.org/10.3390/su9010046

Although burial is widely used to dispose of the large number of pig carcasses generated from FMD outbreaks, this disposal method has not undergone comprehensive scientific investigation. After the burial of culled pigs, dissolved components from carcass decomposition are slowly released into the external environment in the form of leachate, depending on the local environmental conditions. Nevertheless, the properties of groundwater, including total bacterial count, fecal coliform, Salmonella spp., nitrite-N, nitrate-N, ammonium-N, sulfate, NPOC, total oil, and TDS, are recognized as indicators of groundwater contamination resulting from the pig carcass burial during the FMD outbreak in Taiwan. Because very few studies have been performed, there is not enough information on the characteristics of groundwater at the burial sites, duration of pig carcass decomposition, and effects of leachate on groundwater quality worldwide. Although information on the biological and chemical characteristics of leachate is gradually being accumulated from the limited number of studies, guidelines for groundwater quality control should be established for livestock carcass disposal in all modern countries.

52. Isakson, Hans R. An analysis of the impact of swine CAFOs on the value of nearby houses. Agricultural Economics. November 2008; pages 365-372.

Link: https://doi.org/10.1111/j.1574-0862.2008.00339.x

The impact of 39 swine confined or concentrated animal feeding operations (CAFOs) in Black Hawk County, Iowa on 5,822 house sales is explored by introducing a new variable that more accurately captures the effects of prevailing winds, exploring potential adverse effects within concentric circles around each CAFO, managing selection bias, and incorporating spatial correlation into the error term of the empirical model. Large adverse impacts suffered by houses that are within 3 miles and directly downwind from a CAFO are found. Beyond 3 miles, CAFOs have a generally decreasing adverse impact on house prices as distance to the CAFO increases.

53. Jackson, L, Keeney, D, Gilbert, E. Swine manure management plans in North-Central Iowa: Nutrient loading and policy implications. Journal of Soil and Water Conservation April 2000, 55 (2) 205-212. Link: Swine manure management plans in North-Central Iowa...

Public record were used to document the manure management practices of CAFOs housing 59,700 finishing hogs in a 1,554 ha area of Hamilton County, Iowa. Together, they generated an estimated 811,500 kg of nitrogen (N) each year, more than 70% of which volatilized into the atmosphere. CAFOs minimized the area required for applying manure by underestimating manure N content, projecting above average crop yields, and applying manure to soybeans. Some fields were claimed by more than one operator, and some field sizes were overestimated. Manure application based on crop demand for phosphorus would require 9,350 ha of cropland, compared to the 990 ha actually used. Several policy changes could alleviate the nutrient management problems.

54. Jahne MA, Rogers SW, Holsen TM, Grimberg SJ, Ramler IP. Emission and dispersion of bioaerosols from dairy manure application sites: Human health risk assessment. Environ Sci Technol. 2015; 49(16):9842-9849.

Link: https://www.ncbi.nlm.nih.gov/pubmed/26158489

55. Johns Hopkins Bloomberg School of Public Health. Putting Meat on the Table: Industrial Farm Animal Production in America. January 2008

Link: Putting-the-meat-on-the-table.pdf (jhsph.edu)

One of the most serious unintended consequences of industrial food animal production is their growing public health threat. They can be harmful to workers, neighbors, and even those living far from the facilities through air and water pollution, and via the spread of disease. Workers in and neighbors experience high levels of respiratory problems. In addition, workers can serve as a bridging population, transmitting animal-borne diseases to a wider population. A lack of appropriate treatment of enormous amounts of waste may result in contamination of nearby waters with harmful levels of nutrients and toxins, as well as bacteria, fungi, and viruses.

56. Kilpatrick, J. Concentrated Animal Feeding Operations and Proximate Property Values. The Appraiser Journal, July 2001 Pages: 301-306.

Link: Concentrated Animal Feeding Operations and Proximate Property Values (state.ar.us)

Property located near a concentrated animal feeding operation (CAFO) will be negatively impacted by this externality. The degree of impairment depends on proximity and property type and use. Properties with higher unimpaired values are probably impacted more than otherwise lower valued properties.

57. Kilpatrick, J. Animal Operations and Residential Property Values. The Appraisal Journal, Winter 2015: 41-50

Link: animaloperationsJKwinter2015.pdf (greenfieldadvisors.com)

Animal feeding and processing operations have grown more concentrated, with each facility handling much larger numbers of animals than traditional farms. The larger concentration of animals impacts the quality of surrounding air and water. In addition, the facilities impact the economic conditions of the communities where they are located. All of these factors can potentially affect the value of nearby houses. This article summarizes the current literature on how animal operations may affect the value of residential properties located near such facilities... Overall, the empirical evidence indicates that residences near Animal Operations are significantly affected, and data seems to suggest a valuation impact of up to 26% for nearby properties, depending on distance, wind direction, and other factors. Further, there has been some suggestion that properties immediately abutting an AO can be diminished as much as 88%. Not only are residences affected, but nearby small farms can be impacted by such factors as water degradation and insects.

58. Kikuti, M, Paploski IA, et al. Newly emerging PRRSV Lineage 1C variant nomenclature. Swine Health Information Center 2021

Link: SHMP 2020l21.34 [Lineage 1C variant nomenclature].pdf

Recent outbreaks caused by a highly similar PRRSV variant have been reported. As we move forward with investigations of these farm level outbreaks, we continue to confirm that these form a tight genetic cluster not similar (using a 98% nucleotide identity as a cutoff) to any other sequences from our dataset. Because this is such a specific variant and because the common nomenclature used in the field has been restriction fragment length polymorphism (RFLP) typing, a review of the limitations of different PRRSV classification systems is warranted.

59. Kim, J, Goldsmith P. Using Spatial Econometrics to Assess the Impact of Swine Production on Residential Property Values American Agricultural Economics Association, Denver, July, 2004 Link: Microsoft Word - Paper 2 v.4pete.doc (rosemonteis.us)

A spatial hedonic model is developed to assess monetary harm of confined animal feeding operations (CAFOs) on property values, taking explicitly spatial dependence in property values into account. Spatial autocorrelation was found in the form of spatial lag dependence, not spatial error dependence. When spatial lag dependence is explicitly taken into account, on average the impact is reduced by 18%. The magnitude of the spatial autoregressive parameter was about 0.2 for the 1-mile distance band, meaning one-fifth of the house value could be explained by the values of the neighboring houses.

60. Knobeloch L, Salna B, Hogan A, Postle J, Anderson H. Blue babies and nitrate-contaminated well water. Environ Health Perspect. 2000;108(7):675-678.

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1638204/

Two cases of infant methemoglobinemia associated with nitrate contaminated private well water were described in this paper. The case studies underscore the danger that this contaminated water poses to infants during the first six months of life, as well as the risks of long-term exposure, which include cancer, thyroid disease and diabetes. Steps to reduce nitrate inputs in groundwater and routine well water testing are recommended to protect health.

61. Knobeloch, L., Gorski, P., Christenson, M., & Anderson, H. (2013). Private drinking water quality in rural Wisconsin. Journal of environmental health, 75(7), 16–20.

Link: Private drinking water quality in rural Wisconsin - PubMed (nih.gov)

Between July 1, 2007, and December 31, 2010, Wisconsin health departments tested nearly 4,000 rural drinking water supplies for coliform bacteria, nitrate, fluoride, and 13 metals as part of a state-funded program that provides assistance to low-income families. The authors' review of laboratory findings found that 47% of these wells had an exceedance of one or more health-based water quality standards. Test results for iron and coliform bacteria exceeded safe limits in 21% and 18% of these wells, respectively. In addition, 10% of the water samples from these wells were high in nitrate and 11% had an elevated result for aluminum, arsenic, lead, manganese, or strontium. The high percentage of unsafe test results emphasizes the importance of water quality monitoring to the health of nearly one million families including 300,000 Wisconsin children whose drinking water comes from a privately owned well.

62. Kravchenko J , Rhew S, Akushevich I, Agarwal P, Lyerly, HK: Mortality and Health Outcomes in North Carolina Communities Located in Close Proximity to Hog Concentrated Animal Feeding Operations. NC Med J Sep-Oct 2018;79(5):278-288.

Link: https://www.ncbi.nlm.nih.gov/pubmed/30228132

Background Life expectancy in southeastern North Carolina communities located in an area with multiple concentrated animal feeding operations (CAFOs) after adjusting for socioeconomic factors remains low. We hypothesized that poor health outcomes in this region may be due to converging demographic, socioeconomic, behavioral, and access- to-care factors and are influenced by the presence of hog CAFOs.

Methods We studied mortality, hospital admissions, and emergency department (ED) usage for health conditions potentially associated with hog CAFOs-anemia, kidney disease, infectious diseases, and low birth weight (LBW)-in North Carolina communities located in zip codes with hog CAFOs (Study group 1), in zip codes with > 215hogs/km2 (Study group 2), and without hog CAFOs (Control group). We compared cause-specific age-adjusted rates, the odds ratios (ORs) of events in multivariable analyses (adjusted for 6 co-factors), and the changes of ORs relative to the distance to hog CAFOs.

Results Residents from Study groups 1 and 2 had higher rates of all-cause mortality, infant mortality, mortality of patients with multimorbidity, mortality from anemia, kidney disease, tuberculosis, and septicemia, and higher rates of ED visits and hospital admissions for LBW infants than the residents in the Control group. In zip codes with > 215hogs/km2, mortality ORs were 1.50 for anemia (P < 0.0001), 1.31 for kidney disease (P < 0.0001), 2.30 for septicemia (P < 0.0001), and 2.22 for tuberculosis (P = 0.0061).

Limitations This study included a lack of individual measurements on environmental contaminants, biomarkers of exposures and co-factors, and differences in residential and occupational locations.

Conclusions North Carolina communities located near hog CAFOs had higher all-cause and infant mortality, mortality due to anemia, kidney disease, tuberculosis, septicemia, and higher hospital admissions/ED visits of LBW infants. Although not establishing causality with exposures from hog CAFOs, our findings support the need for future studies to determine factors that influence these outcomes, as well as the need to improve screening and diagnostic strategies for these diseases in North Carolina communities adjacent to hog CAFOs.

63. Lawley, Chad. Hog Barns and Neighboring House Prices: Anticipation and Post-Establishment Impacts. American Journal of Agricultural Economics. 2021 May; Vol. 103. Issue 3: 1099-1121 Link: https://doi.org/10.1111/ajae.12203

The impact of large-scale hog barns on residential property values is at the forefront of local concerns about livestock development. In this article, I examine the impact of hog barns on house prices in an intensive production region of Manitoba, Canada. Timing of barn establishment and precise locations of houses and barns are used to gain a better understanding of the dynamic impacts of hog barns on house prices. I find that houses within 2 km of a hog barn sell for 5.7% less than similar houses located a little farther away from a barn. Quasi-myopic specifications indicate that house prices fall by 6.2% up to three years prior to barn establishment, consistent with market anticipation of the future location of hog barns. Accounting for anticipation increases the post-establishment discount to 8%, suggesting that ignoring anticipation of new barn establishment biases estimated post-establishment impacts downwards.

64. Lowe, J., Gauger, P., et.al. (2014). Role of Transportation in Spread of Porcine Epidemic Diarrhea Virus Infection, United States. Emerging Infectious Diseases, 20(5), 872-874.

Link: https://doi.org/10.3201/eid2005.131628

Harvest facilities serve as a source of contact between many swine farms with different health statuses. This study suggests that collection points, such as harvest facilities and livestock auction markets, can be an efficient source of contamination of transport vehicles that return to pig farms and likely played a role in rapidly disseminating PEDV across vast geographic regions shortly after PEDV was first identified in the United States. These data also suggest that the contamination of transport vehicles leaving the harvest facilities increased as the prevalence of PEDV–positive transport vehicles and virus load coming into the facility increased.

65. Ma W, Lager KM, Vincent AL, Janke BH, Gramer MR, Richt JA. The role of swine in the generation of novel influenza viruses. Zoonoses Public Health. 2009 Aug;56(6-7):326-37. Link: https://www.ncbi.nlm.nih.gov/pubmed/19486316

The ecology of influenza A viruses is very complicated involving multiple host species and viral genes. Avian species have variable susceptibility to influenza A viruses with wild aquatic birds being the reservoir for this group of pathogens. Occasionally, influenza A viruses are transmitted to mammals from avian species, which can lead to the development of human pandemic strains by direct or indirect transmission to man. Because swine are also susceptible to infection with avian and human influenza viruses, genetic reassortment between these viruses and/or swine influenza viruses can occur. The potential to generate novel influenza viruses has resulted in swine being labelled 'mixing vessels'. The mixing vessel theory is one mechanism by which unique viruses can be transmitted from an avian reservoir to man. Although swine can generate novel influenza viruses capable of infecting man, at present, it is difficult to predict which viruses, if any, will cause a human pandemic. Clearly, the ecology of influenza A viruses is dynamic and can impact human health, companion animals, as well as the health of livestock and poultry for production of valuable protein commodities. For these reasons, influenza is, and will continue to be, a serious threat to the wellbeing of mankind.

66. Malecki, K., Schultz, A. A., Severtson, D. J., Anderson, H. A., & VanDerslice, J. A. (2017). Private- well stewardship among a general population based sample of private well-owners. The Science of the total environment, 601-602, 1533–1543.

Link: https://doi.org/10.1016/j.scitotenv.2017.05.284

Private well stewardship, including on-going testing and treatment, can ensure private well users are able to maintain source-water quality and prevent exposures to potentially harmful constituents in primary drinking water supplies. Unlike municipal water supplies, private well users are largely responsible for their own testing and treatment and well stewardship is often minimal. The importance of factors influencing regular testing, and treatment behaviors, including knowledge, risk perception, convenience and social norms, can vary by geography and population characteristics. The primary goals of this study were to survey a general statewide population of private well users in Wisconsin in order to quantify testing and treatment patterns and gather data on motivations and barriers to well stewardship. The majority of respondents reported using and drinking well water daily but only about one half of respondents reported testing their wells in the last ten years and of these, only 10% reported testing in the last 12months. Bacteria and nitrates were contaminants most often tested; and, a private laboratory most often conducted testing. The most commonly reported water treatment was a water softener. Living in a particular geographic region and income were the most significant predictors of water testing and treatment. Iron and hardness, which influence water aesthetics but not always safety, were the most commonly reported water quality problems. Health concerns or perceived lack thereof were, respectively, motivators and barriers to testing and treatment. Limited knowledge of testing and treatment options were also identified as barriers. Results confirm previous findings that well stewardship practices are minimal and often context specific. Understanding the target population's perceptions of risk and knowledge are important elements to consider in identifying vulnerable populations and developing education and policy efforts to improve well stewardship.

67. Manassaram DM, Backer LC, Moll DM. A review of nitrates in drinking water: Maternal exposure and adverse reproductive and developmental outcomes. Environmental Health Perspectives. 2006.

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1392223/

The relationship between maternal exposure to nitrates through drinking water and adverse reproductive and developmental outcomes was reviewed in this study. Animal studies support the association between nitrate exposure and adverse reproductive effects, and some studies report an association between nitrates in drinking water and spontaneous abortion, intrauterine growth restriction and various birth defects, though a direct exposure-response relationship remains unclear and there is insufficient evidence to establish a causal relationship.

68. Mathewson P, Evans S, Byrnes T, Joos A, Naidenko O. Environmental Monitoring Assessment (2020) 192: 724. Link: Health & economic impact of nitrate pollution in drinking water: a Wisconsin case study

Link: https://doi.org/10.1007/s10661-020-08652-0

Nitrate contamination of drinking water, common in agricultural areas, increases the risk of certain cancers and impacts fetal development during pregnancy. Building on previously published methodology, this study evaluates nitrate-attributable disease cases and adverse birth outcomes as well as their economic costs for Wisconsin, USA. Nitrate is the most common contaminant in groundwater in Wisconsin. Two-thirds of the state’s residents use groundwater as the primary source of drinking water. Here, we analyze nitrate exposure from drinking water in Wisconsin based on nitrate test results for community water systems for the period of 2010–2017 and a novel methodology for estimating nitrate exposure for the 28% of state’s residents who use private wells. We estimate that annually, 111–298 combined cases of colorectal, ovarian, thyroid, bladder, and kidney cancer in Wisconsin may be due to nitrate contamination of drinking water. Each year, up to 137– 149 cases of very low birth weight, 72–79 cases of very preterm birth, and two cases of neural tube defects could be due to nitrate exposure from drinking water. The direct medical cost estimates for all nitrate-attributable adverse health outcomes range between $23 and $80 million annually. Simulating targeted reductions in the counties with the highest current drinking water nitrate concentrations resulted in similar reductions in adverse health outcomes as statewide reduction efforts, up to nitrate reductions of 20%. Time trend analysis suggests that groundwater nitrate concentrations are overall increasing. Thus, nitrate contamination of water supplies in Wisconsin is a public health problem that needs to be addressed.

69. MacDonald G.J., et.al. (2017). Strategies to Improve Private-Well Water Quality: A North Carolina Perspective. Environmental health perspectives, 125(7), 076001.

Link: https://doi.org/10.1289/EHP890

Evidence suggests that the 44.5 million U.S. residents drawing their drinking water from private wells face higher risks of waterborne contaminant exposure than those served by regulated community water supplies. These recommendations could improve the health of North Carolinians facing elevated risks of exposure to waterborne contaminants because of their reliance on inadequately monitored and maintained private wells. Because many of the challenges in N.C. are common nationwide, these recommendations could serve as models for other states.

70. May, J. Estimating Water Usage on Michigan Swine Farms. Michigan State University Extension.

Link: Water_Use_for_Swine_Farms

Swine farms use well water for watering animals, cleaning facilities, animal cooling and in some instances for moving manure from the barn to the storage structure. Most pigs are raised in an all-in/all-out environments where one group of pigs, at the same stage of production, is moved into a location and stays there until that group is ready to move to the next location or on to slaughter. Between groups the facility is thoroughly cleaned by pre-soaking and/or pressure washing.

71. Milligan, W. R., Fuller, Z. L., Agarwal, I., Eisen, M. B., Przeworski, M., & Sella, G. (2021). Impact of essential workers in the context of social distancing for epidemic control. PloS one, 16(8), e0255680.

Link: https://doi.org/10.1371/journal.pone.0255680

New emerging infectious diseases are identified every year, a subset of which become global pandemics like COVID-19. In the case of COVID-19, many governments have responded to the ongoing pandemic by imposing social policies that restrict contacts outside of the home, resulting in a large fraction of the workforce either working from home or not working. To ensure essential services, however, a substantial number of workers are not subject to these limitations, and maintain many of their pre-intervention contacts. To explore how contacts among such "essential" workers, and between essential workers and the rest of the population, impact disease risk and the effectiveness of pandemic control, we evaluated several mathematical models of essential worker contacts within a standard epidemiology framework. The models were designed to correspond to key characteristics of cashiers, factory employees, and healthcare workers. We find in all three models that essential workers are at substantially elevated risk of infection compared to the rest of the population, as has been documented, and that increasing the numbers of essential workers necessitates the imposition of more stringent controls on contacts among the rest of the population to manage the pandemic. Importantly, however, different archetypes of essential workers differ in both their individual probability of infection and impact on the broader pandemic dynamics, highlighting the need to understand and target intervention for the specific risks faced by different groups of essential workers. These findings, especially in light of the massive human costs of the current COVID-19 pandemic, indicate that contingency plans for future epidemics should account for the impacts of essential workers on disease spread.

72. Mirabelli MC, Wing S, Marshall SW, Wilcosky TC. Asthma symptoms among adolescents who attend public schools that are located near confined swine feeding operations. Pediatrics. 2006;118(1):e66-75.

Link: http://pediatrics .aappublications .org/content/118/1/e66/

The relationship between exposure to airborne effluent from swine CAFOs and asthma symptoms in adolescents age 12-14 years old was assessed in this study to better understand the health effects of living near industrial swine facilities. The study found that estimated exposure to swine CAFO air-pollution was associated with wheezing symptoms in adolescents.

73. Morrow, WE, Ferket, PR. Alternative Methods for the Disposal of Swine Carcasses Factsheet. North Carolina State University, Raleigh, NC Nov 2001. ANS01-815S

Link: https://projects.ncsu.edu/project/swine_extension/publications/factsheets/815s.pdf

There is probably no one best way to dispose of swine mortality carcasses. The optimum system for any particular farm location would need to be selected based on a number of criteria, including the current state of the protein/oil market, the biosecurity required, the distance to processing sites, the local public's perception, and the government regulations that apply to that location. The tonnage of dead pigs produced annually is substantial. A typical 5000 sow farrow-to-finish farming system (with mortality losses of 7%, 10%, 5%, 1%, and 1% in the sow, neonatal, nursery, growing, and finishing herd, respectively) will produce over 200,000 pounds of dead pigs annually. In many farming systems in the USA, actual losses may be much higher. The