Epidemiological analysis of acute respiratory disease (ARD) and characteristics of the influenza epidemic in Bohemia during the season 1986/1987.

The authors analyze the findings of epidemiological and virological surveillance of ARD in Bohemia during the season 1986/1987. In all, 57.5% of the Czech population was affected by acute respiratory disease (ARD). There were 5,950,832 cases reported, 124,444 complications (2.1% of the overall morbidity rate) and 5,374 deaths due to influenza, bronchitis, pneumonia and chronic pulmonary affection. The influenza epidemic commenced during the 48-th calendary week (CW) and lasted 5 weeks till the 52-nd CW. The epidemic was due to an influenza virus strain of the subtype A(H1N1) antigenically related to the drift variant A (Singapore) 6/86. Within an extremely short period of the epidemic, 1,094,865 influenza cases were reported and 22,313 cases of complications. 10.7% of the CSR population were affected during the epidemic in whose etiology noninfluenza respiratory viruses were significantly implicated, especially adenoviruses (41.7%) and the RS virus (26.9%). There was no excessive mortality in the course of the epidemic. The authors discuss the atypical nature of this particular influenza epidemic and the etiological role of respiratory viruses.