Rising Temperatures and Food-Borne Illnesses
Lake, I.R., Gillespie, I.A., Bentham, G., Nichols, G.L., Lane, C., Adak, G.K. and Threlfall, E.J. 2009. A re-evaluation of the impact of temperature and climate change on foodborne illness. Epidemiology and Infection 137: 1538-1547.
To gain a better understanding of these coupled phenomena and see how their relationships may have changed over the years, the seven scientists studied food poisoning, campylobacteriosis, salmonellosis, Salmonella Typhimurium infections and Salmonella Enteritidis infections in England and Wales from the mid-1970s and early 1980s to 2007, based on data obtained from the UK's Office for National Statistics and its Health Protection Agency.
The work of the United Kingdom researchers revealed that all five of the maladies they studied "were positively associated (P<0.01) with temperature in the current and previous week," and that "food poisoning, salmonellosis and S. Typhimurium infections were also associated with temperature 2-5 weeks previously (P<0.01)," supportive of the view that rising temperatures could indeed lead to increases in these health problems. However, they also found "there were significant reductions in the impact of temperature on foodborne illnesses over time," consistent with "reduced pathogen concentrations in food and improved food hygiene over time."
Lake et al. note that some prior studies -- Bentham and Langford (2001), Ebi et al. (2006) and McMichael et al. (2006) -- have extrapolated results of the incidence of foodborne illness as a function of temperature into the future, with the result that they portend increases in foodborne illnesses in a warming world. Their results, however, suggest that this tendency can actually be reversed "through reducing the pathogen levels in major food groups and improving food hygiene at the domestic and institutional level," as has successfully been done in England and Wales.
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