"relative frequency of parainfluenza infection in patients with respiratory infections"

according to statistical data from who, respiratory tract infections are among the most important health problems all over the world. differentiating viral from other causes of respiratory infections is difficult, but a good knowledge of viral etiologic factors can guide the physicians in the diagnosis and treatment of the disease. we carried out this descriptive, case-series study to evaluate the relative frequency of parainfluenza virus (piv) infections in upper and lower respiratory tract infections. a total of 263 three children with respiratory infection were studied from autumn 1998 to autumn 2000. we prepared samples from their nasopharynx with sterile swabs for viral culture and study of cytopathic effects of piv. thirty six cases had positive culture for piv (14%). there was a significant statistical correlation between the prevalence of piv infection and age of patients. the highest prevalence was in the of 1-5 years old age group. there was also a correlation with season, and majority of cases were seen in autumn and spring (p< 0.0001). there was no significant correlation between piv infection and sex. piv infection had significant correlation with croup and bronchiolitis (p<0.0001). piv plays an important role in causing lower respiratory tract infections.