Prevalence and Clinical Features of RSV Bronchiolitisin Hospitalised Children Under Two Years at the UTH Children's Hospital, Lusaka, Zambia

Background: Bronchiolitis is a major cause of hospitalization in children under the age of two, and it occurs primarily in the winter, though it can occur at any time of year. The bulk of the causes are viral, with Respiratory Syncytial Virus being the most common. RSV has been linked to a low fatality rate but a high morbidity rate, which includes severe symptoms and a lengthy hospital stay. The goal of the study was to find out about bronchiolitis trends, the prevalence of RSV bronchiolitis, its clinical features, and the impact on severity and hospital stay. Methods: A cross-sectional study was done on children less than two years admitted with clinical bronchiolitis to UTHs-CH, Lusaka Zambia. Nasopharyngeal (NP) swabs were collected and samples analyzed by rRT-PCR for RSV. Risk factors and severity of bronchiolitis were determined on admission while length of stay, HIV status and secondary outcome (died, still in hospital, discharged) were determined on day 7 of hospital admission. Results: We enrolled 181 Children with median age five months. Two-thirds were male and more than 90% had a mother alive. The prevalence of RSV was 25.4% (95% CI; 19.5-32.2). The highest number of patients were in April while the lowest numbers were observed in July in RSV negative and in June for RSV positive. More than two thirds had severe symptoms and congenital heart disease was significantly found to be risk factor for severe symptoms (P value 0.010). No independent clinical features were associated with RSV and no difference was found in severity between RSV positive and RSV negative bronchiolitis. The median length of hospital stay was five days and six days for RSV negative and RSV positive respectively and case fatality rate of RSV bronchiolitis was 2.2%. Conclusion: The 25.4% laboratory confirmed detection rate for RSV during the study period may be low. Because the samples were taken during the COVID-19 pandemic, interventional measures to combat COVID 19 may have helped to reduce the spread of RSV. Because clinical features of RSV are like those of other respiratory viruses, a clinical diagnosis may be impossible, necessitating the use of PCR to confirm the diagnosis.