title: The effect of temperature on different Salmonella serotypes during warm seasons in a Mediterranean climate city, Adelaide, Australia.
abstract: Changing trends in foodborne disease are influenced by many factors, including temperature. Globally and in Australia, warmer ambient temperatures are projected to rise if climate change continues. Salmonella spp. are a temperature-sensitive pathogen and rising temperature can have a substantial effect on disease burden affecting human health. We examined the relationship between temperature and Salmonella spp. and serotype notifications in Adelaide, Australia. Time-series Poisson regression models were fit to estimate the effect of temperature during warmer months on Salmonella spp. and serotype cases notified from 1990 to 2012. Long-term trends, seasonality, autocorrelation and lagged effects were included in the statistical models. Daily Salmonella spp. counts increased by 1·3% [incidence rate ratio (IRR) 1·013, 95% confidence interval (CI) 1·008-1·019] per 1 °C rise in temperature in the warm season with greater increases observed in specific serotype and phage-type cases ranging from 3·4% (IRR 1·034, 95% CI 1·008-1·061) to 4·4% (IRR 1·044, 95% CI 1·024-1·064). We observed increased cases of S. Typhimurium PT9 and S. Typhimurium PT108 notifications above a threshold of 39 °C. This study has identified the impact of warm season temperature on different Salmonella spp. strains and confirms higher temperature has a greater effect on phage-type notifications. The findings will contribute targeted information for public health policy interventions, including food safety programmes during warmer weather.
authors.affiliation: School of Public Health,The University of Adelaide,Adelaide,SA,Australia.
authors.forename: A
authors.initials: A
authors.lastname: Milazzo
authors.affiliation: School of Public Health,The University of Adelaide,Adelaide,SA,Australia.
authors.forename: L C
authors.initials: LC
authors.lastname: Giles
authors.affiliation: School of Public Health,The University of Adelaide,Adelaide,SA,Australia.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Communicable Disease Control Branch,Department for Health and Ageing,Adelaide,SA,Australia.
authors.forename: A P
authors.initials: AP
authors.lastname: Koehler
authors.affiliation: School of Public Health,The University of Adelaide,Adelaide,SA,Australia.
authors.forename: J E
authors.initials: JE
authors.lastname: Hiller
authors.affiliation: School of Public Health,The University of Adelaide,Adelaide,SA,Australia.
authors.forename: P
authors.initials: P
authors.lastname: Bi
mesh_terms: D057231:Climate Change; D018563:Disease Notification; D005517:Foodborne Diseases / Q000453:epidemiology / Q000382:microbiology*; D006358:Hot Temperature; D012475:Salmonella / Q000235:genetics / Q000502:physiology*; D012480:Salmonella Infections / Q000453:epidemiology / Q000382:microbiology*; D012621:Seasons; D065288:Serogroup; D013021:South Australia / Q000453:epidemiology; D013045:Species Specificity
keywords: Climate – impact of; Salmonella; Salmonella typing; foodborne infections; infectious disease epidemiology