Coxsackie infection and births of future diabetic children: year, seasonality and secularity.

BACKGROUND: Environmental factors including Coxsackie virus infections are considered as one of the etiopathogenetic mechanisms in childhood insulin dependent diabetes mellitus (IDDM). HYPOTHESIS: This relationship should be reflected not only in similar seasonal and secular periodicities of Coxsackie epidemics and IDDM incidence but also in the cycling of births of future diabetic children. SUBJECTS: Seven hundred and seven healthy Slovak children randomly selected in 1985-98 were investigated for the presence of actual Coxsackie infection. The months of birth in 1970-93 of 1779 Slovak children with later IDDM were registered. AntiCoxsackie positivity was determined in 1978-91 at IDDM onset in 336 children. METHODS: AntiCoxsackie positivity was assessed by IgM antibodies and virus neutralization test. Time series data were processed by cosinor regression enabling the definition of statistical significance of trends and of cycles with tested period lengths. RESULTS: Marked autumnal peaks were found for Coxsackie infections. For births of future diabetics, both autumn and spring peaks were encountered. Moreover, seven-year cycling displayed peaks in 1990 and 1997 for Coxsackie and 1976, 1983 and 1990 for IDDM births. CONCLUSIONS: Connection between Coxsackie viral infections and births of future diabetic children appears plausible also in Slovakia.