Seasonal prevalence and chronobiology of some notifiable infectious diseases

The aim of this study is to investigate retrospectively whether 13 notifiable infectious diseases [acute bloody diarrhea, amoebic dysentery, bacillary dysentery, brucellosis, hepatitis A, hepatitis B, mumps, scarlet fever, suspicious bites (potential rabies exposures), streptococcal sore throat, anthrax, cutaneous leishmaniasis and typhoid fever] in Turkey with high incidance show a seasonal rhythm.The monthly data between 2000 and 2008 of notifiable infectious diseases obtained from Republic of Turkey Ministry of Health, Basic Health Services, Department of Infectious Diseases were used for the arrangement of seasonal tables and the statistical evaluation. Mean cases of infectious diseases due to seasons of year were analyzed by One-way ANOVA. Post-hoc Tukey test was used for multiple comparation.Bacillary dysentery, acute bloody diarrhea, brucellosis and suspicious bites cases peaked in summer, while cutaneous leishmaniasis and scarlet fever were more frequent during spring. Mean number of cases of amoebic dysentery and anthrax significantly increased during summer and autumn compared to winter and spring; Hepatitis A cases were significantly higher in winter and autumn when compared to spring and summer; and streptococcal sore throat in winter and spring when compared to summer. Hepatitis B, mumps and typhoid fever cases showed no significant seasonal difference.This study is the first study that seasonal rhythms of these 13 diseases were assessed in Turkey. It is considered that the results of the study would be useful to predict the long-term risks of infectious diseases and to develop new strategies and preventive implications for control of these diseases.