"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

The Genetic Diversity and Phylogenetic Characteritics of Rotavirus VP4(P) Genotypes in Children With Acute Diarrhea

Background: Acute gastroenteritis is a major cause of morbidity and mortality among children in developing countries. Rotaviruses are recognized as the most common etiologic factors of gastroenteritis. In this study, we determined the epidemiologic features, clinical symptoms and molecular structure of rotavirus VP4(P) genotypes in children with acute diarrhea in Bahrami Hospital in Tehran Iran, during 2009 for justifying the routine use of rotavirus vaccines in children. Methods: One hundred fifty fecal samples from 150 children with acute diarrhea in Bahrami Pediatric Hospital in Tehran, Iran were collected from January to December 2009. The patients’ mean age was 20.90+18.19 years (ranging from 1 month to 14 years). Fecal samples were transported on ice to the laboratory of virology department of Pasture Institute of Iran. The demographic and clinical data for each case were entered in an author-devised questionnaire. Group A rotavirus was detected by dsRNA-PAGE. Subsequently, rotavirus genotyping (VP4) was performed by semi-nested multiple RT-PCR and the phylogenetic tree of the Rotavirus nucleotides was constructed. The data were analyzed by statistical tests including Wilcoxon signed and Mann-Whitney U. Results: Rotavirus was isolated in 19.3% of the samples, more than 90% of which had long RNA patterns. The predominant genotype (VP4) was P[8] (86%) and other genotypes respectively were P[6] (6.9%) and P[4] (6.9%). Conclusion: A high prevalence of the P[8] genotype was found to be the cause of acute diarrhea. The analysis of P[8] genotype sequence showed a high level of similarity of the virus in this study with those of other Asian countries