Estimated burden of respiratory syncytial virus infection in Ulaanbaatar

Abstract

Background: Respiratory syncytial virus (RSV) is one of the pathogens that is widespread among the world’s population and usually affects the lower respiratory tract of infants and young children[1]. It is a leading cause of morbidity and mortality in children, mostly in lowand middle-income countries, and according to the 2016 Global Burden of Disease Estimates, 60%-70% of young children are infected with the virus before the age of 1, of which 2%-3% are hospitalized[2]. Estimating the burden of respiratory syncytial virus on the population and determining its epidemiology, clinical, and virological characteristics will be of great importance in creating the necessary evidence for the proper planning and implementation of public health measures, and in making evidence-based decisions. Aim: To estimate some epidemiological characteristics of respiratory syncytial virus infection in the population of Ulaanbaatar and the burden on the population Materials and Methods: The research was conducted using the descriptive research method, based on the quantitative data of cases of respiratory syncytial virus recorded by active surveillance of 7 district general hospitals of Ulaanbaatar from May 2017 to April 2019. Results: In this study, we estimated seasonality and disease burden of respiratory syncytial virus using data from 1,665 individuals registered at 7 study units between May 2017 and April 2019. Of the respondents, 873 (52.4%) were male, 792 (47.6%) were female, and 79.5% (1325) were children under the age of 5, of which 54.8% (911) were under the age of 2. When considering respiratory syncytial virus positive cases by clinical symptoms, tachyponea (rr>40) in 63% (260), wheezing in 60% (249), chest-indraw in 45% (188), and fever in 40% (164). When considering the clinical symptoms by age group, chest-indraw in children less than 3 months old (8.5%), apnea in children aged 3-5 months (50%), chest-indraw in children aged 6-11 months (24.5%), sepsis in 12-23 months (45.5%), fever (32.9%) in 2-4-year-old children, and fever (7.3%) in people over 5 years old. When comparing the positive cases of respiratory syncytial virus infection by age group, the burden of disease was highest among children aged 3-5 months (68%) in the 2 years of the study, while the burden of influenza infection was higher among children aged less than 3 months (21%). When considering the seasonality of respiratory syncytial virus, the activity of respiratory syncytial virus increases from October, the disease reaches its peak in December and continues until April. It is observed that when the activity of respiratory syncytial virus decreases, the activity of influenza virus increases. Conclusion: Respiratory syncytial virus infection has a higher burden of disease among children under 5 years of age than in other age groups, especially in children under 6 months of age. The activity of respiratory syncytial virus increases from October, the disease reaches its peak in December and lasts until April. When the activity of respiratory syncytial virus decreases, the activity of influenza virus increases.