Epidemiological picture of respiratory viral infections in Croatia.

This paper presents the epidemiological study of respiratory viral infections in Croatia from 1 September 1986 till 31 August 1987. A total of 527 patients with acute respiratory diseases were examined. Their nasopharyngeal secretion and/or throat swab were taken and the viruses were demonstrated by the method of direct viral diagnosis (isolation and rapid immunofluorescent detection). This 12-month study on acute respiratory infections in Croatia in 1986/1987 shows that viruses were the agents in 47.2% of these infections. Out of a total of 527 patients with acute respiratory disease, 177 patients had RSV (prevalence 33.6%), 40 adenovirus (prevalence 7.6%), 18 enterovirus (prevalence 3.4%), 12 parainfluenza (prevalence 2.3%), 8 herpes simplex virus (prevalence 1.3%) and 3 influenza virus (prevalence 0.6%) infection; (9 patients had mixed infections with two viruses). Viral etiology was proved in 44.0% of upper respiratory tract infections, 86.5% of bronchiolitis, 63.3% of pneumonia, 57.5% of bronchitis, and 33.3% of croup. The epidemical wave of RSV infections started in October 1986 and lasted for the next 7 and a half months with a peak in December 1986. Infections with parainfluenza occurred in November 1986 and subsided in March 1987 with a peak in December 1986. An epidemic of adenovirus occurred in two waves and lasted throughout 9 months. Enteroviruses caused infections during the fall and at the beginning of the winter 1986 but also again in the spring 1987.