Animal sentinels

There is increasing recognition that wild, domestic, and companion animals may act as "sentinels" for environmental health hazards by providing early warning of human health hazards in the environment. Animals can act as sentinels because they may be more susceptible or have greater exposure to a particular hazard compared to humans living nearby.

Detection of toxic gases

The classic example of animals serving as sentinels is the "canary in the coal mine". Well into the 20th century, coal miners in the United Kingdom and the United States brought canaries into coal mines as an early-warning signal for toxic gases including methane and carbon monoxide. The birds, being more sensitive, would become sick before the miners, who would then have a chance to escape or put on protective respirators.

Disease detection by disease emergence in animals

Infectious diseases

The discovery of West Nile Virus in the western hemisphere was heralded by an outbreak of disease in crows and other wild birds. Other emerging diseases have demonstrated linkages between animal health events and human risk, including Monkeypox, SARS, and Avian Influenza.

Household toxin hazards

Dogs may provide early warning of lead poisoning hazards in a home, and certain cancers in dogs and cats have been linked to household exposures to pesticides, cigarette smoke, and other carcinogens.

Disease detection via animals sensing the disease

Cancer detection

A study has shown that dogs, with often only relatively short training, can detect lung and breast cancer trace elements in the breath of people with these cancers, and clearly distinguish them from the breath of healthy subjects.^[1]

Terrorist events

Some speculate that animals could provide early warning of a terrorist attack using biological or chemical agents. Since most potential bioterrorism threats are zoonoses (infectious diseases of animal origin), animals could also be at risk from a terrorism attack and may be first to show signs of illness due to increased exposure or susceptibility. For example, when anthrax was inadvertently released from a Soviet weapons facility in Sverdlovsk, livestock died at a greater distance from the plant compared to human cases.

"One Health"

Recently, there has been a call for linkage of human and veterinary medicine in a "One Health" approach that recognizes disease events in non-human species may indicate human health risk. The "One Health" approach involves greater information sharing between human health and veterinary clinicians and public health professionals and cooperative efforts to identify and prevent diseases that act across species barriers in a way that is mutually beneficial.

See also

• Indicator species

References

1. ^ "Dogs Smell Cancer in Patients' Breath, Study Shows". National Geographic News. 12 January 2006. http://news.nationalgeographic.com/news/2006/01/0112_060112_dog_cancer.html. Retrieved 31 August 2011. 

• van der Schalie WH, Gardner HS Jr, Bantle JA, De Rosa CT, Finch RA, Reif JS, Reuter RH, Backer LC, Burger J, Folmar LC, Stokes WS. (Apr 1999). "Animals as sentinels of human health hazards of environmental chemicals". Environ Health Perspect 107 (4): 309–315. 
• O'Brien DJ, Kaneene JB, Poppenga RH (Mar 1993). "The use of mammals as sentinels for human exposure to toxic contaminants in the environment". Environ Health Perspect 99: 351–368. PMID 8319652. 
• Backer LC, Grindem CB, Corbett WT, Cullins L, Hunter JL (2001-07-02). "Pet dogs as sentinels for environmental contamination". Sci Total Environ 274 (1–3): 161–169. doi:10.1016/S0048-9697(01)00740-9. 
• Rabinowitz P, Gordon Z, Chudnov D, Wilcox M, Odofin L, Liu A, Dein J. (Apr 2006). "Animals as sentinels of bioterrorism agents". Emerg Infect Dis 12 (4): 647–652. PMID 16704814. 
• Meselson M, Guillemin J, Hugh-Jones M, Langmuir A, Popova I, Shelokov A, Yampolskaya O (1994-11-18). "The Sverdlovsk anthrax outbreak of 1979". Science 266 (5188): 1202–1208. doi:10.1126/science.7973702. PMID 7973702. 
• Kahn LH. (Apr 2006). "Confronting zoonoses, linking human and veterinary medicine". Emerg Infect Dis 12 (4): 556–561. 

External links

• The Canary Database: Animals As Sentinels of Human Environmental Health Hazards