Seasonality in six enterically transmitted diseases and ambient temperature

Abstract

We propose an analytical and conceptual framework for a systematic and comprehensive assessment of disease seasonality to detect changes and to quantify and compare temporal patterns. To demonstrate the proposed technique, we examined seasonal patterns of six enterically transmitted reportable diseases (EDs) in Massachusetts collected over a 10-year period (1992-2001). We quantified the timing and intensity of seasonal peaks of ED incidence and examined the synchronization in timing of these peaks with respect to ambient temperature. All EDs, except hepatitis A, exhibited well-defined seasonal patterns which clustered into two groups. The peak in daily incidence of Campylobacter and Salmonella closely followed the peak in ambient temperature with the lag of 2-14 days. Cryptosporidium, Shigella, and Giardia exhibited significant delays relative to the peak in temperature (approximately 40 days, P<0.02). The proposed approach provides a detailed quantification of seasonality that enabled us to detect significant differences in the seasonal peaks of enteric infections which would have been lost in an analysis using monthly or weekly cumulative information. This highly relevant to disease surveillance approach can be used to generate and test hypotheses related to disease seasonality and potential routes of transmission with respect to environmental factors.

Salmonellae in the Environment

“…The peak of nontyphoidal salmonellae infection in the community was recorded during summer months (June-September) in the majority of Eropean, Mediterranean countries and North America. The summer seasonality was more marked in northern/western Europe than in the Mediterranean region (Ekdahl et al, 2005;Naumova et al, 2007). Similarly, in Korea the highst peak of nontyphidal salmonellae infection in the community was recorded during the summer (June-August) (Cho et al, 2008).…”

Population based self-reported acute gastrointestinal infection in slovenia: multiplier study

“…AGI rise in the summer and decline in the winter. Enteric infections caused by the protozoans Giardia and Cryptosporidium also exhibit seasonal variation, but it is shifted towards autumn (17). In contrast, seasonality is not marked for hepatitis A and shigellosis (17).…”

“…Enteric infections caused by the protozoans Giardia and Cryptosporidium also exhibit seasonal variation, but it is shifted towards autumn (17). In contrast, seasonality is not marked for hepatitis A and shigellosis (17). Infections caused by Salmonella and Campylobacter closely follow the ambient temperature curve of the environment.…”

Estacionalidad Y Causas De Muerte en Los Valles Calchaquíes (Argentina): Siglo Xix

“…De acuerdo a lo señalado por Naumova et al (2007), los picos estacionales para algunas enfermedades transmitidas por agua y alimentos se asocian a las temperaturas más cálidas del año. Esto se refleja al detectarse en los registros de las parroquias que las enfermedades infecciosas de transmisión por agua y alimentos con el cólera y los "cólicos", como causas más frecuentes de defunción, se producen principalmente durante los meses del periodo estival.…”