Social Responsibility - Public Health
Microorganisms such as bacteria, viruses, parasites and protozoa can be found in soil and water as well as in humans, animals and their waste products. In people and animals, many microorganisms are normal components of the body and do not usually cause disease.
Microorganisms that may cause disease are referred to as pathogens.1Pathogens may be present in the pork production environment but exposure normally doesn't lead to disease. Reports of illness in people due to exposure to animal pathogens in the environment are uncommon, and it is even more uncommon that those illnesses would be due to pathogens from pigs.2
Transmission of pathogens from animals to people is possible via contact, ingestion or inhalation. Exposure most commonly involves direct contact with the animals, animal manure, animal products or contaminated water. Some pathogens can be transported through the air on dust particles. However, there is currently no evidence that animal pathogens are transferred to people over long distances through the air.3
Proper manure storage and land application of manure is designed to minimize any risks to surface or ground water. Storing or composting manure before it is applied to fields as a fertilizer decreases the presence of pathogens.2 Once manure is applied to the land, microbes in the soil readily destroy most pathogens by initiating a pathogen inactivation process. Furthermore, many bacteria and most viruses are sensitive to sunlight. Both bacteria and viruses die over time as they are dried out.4
Proper manure storage systems, just as residential septic systems, are designed to minimize contamination of surface and ground water. However, residents in rural areas should test their wells annually because there are many other potential sources of water contamination.5
References:
1 Medline Plus Medical Dictionary http://www2.merriamwebster.com/cgi-bin/mwmednlm?book=Medical&va=pathogens
2 Guan TY and Halley RA. 2003. Pathogens in the SwineManure Environments and Transmission of Human EntericIllness - A Review. Journal of Environmental Quality. 32:383-392.
3 United States Geological Survey. 2002. Water-Quality Data for Pharmaceuticals, Hormones, and other OrganicWastewater Contaminants in U.S. Streams, 1999-2000.
4 Accessed September 27, 2007 http ://toxics.usgs.gov/pubs/OFR-02-94/#occurrenceAccessed September 27, 2007. http://www.gov.mb.ca/agriculture/livestock/publicconcerns/cwa01s04.html
5 Centers for Disease Control and Prevention. Private WellResources. http://www.cdc.gov/ncidod/dpd/healthywater/privatewell.htmaccessed September 27, 2007
