Prevalence and severity of respiratory syncytial virus infections in
children in Central African Republic, 2015 to 2018
Abstract
Background: Respiratory syncytial virus (RSV) is one of the main viral
pathogens causing acute respiratory infections in children under 5 years
of age, but has seldom been studied in Central African Republic (CAF).
Methods: Taking advantage of the national influenza surveillance network
in CAF, a total of 3903 children under 5 years matching the
influenza-like illness (ILI, 68.5%) or severe acute respiratory
infection (SARI, 31.5%) case definitions were recruited from January
2015 to December 2018 to determine annual RSV prevalence, seasonality
and disease severity as well as to characterise RSV strains. The
presence of RSV viral RNA in nasopharyngeal samples was assessed by
RT-PCR, followed by RSV-A and –B typing and Sanger sequencing. Results:
RSV incidence was significantly higher in infants < 6 months
(13.4%), in hospitalized children (13.3% vs 5.5%) and in male
patients (9.5% vs 6.4%). An overall prevalence of RSV of 8.0% in the
period of 2015-2018 was shown, with significant annual (6.4%-10.6%)
and seasonal (12.7% in rainy season vs 3.0% in dry season)
fluctuations. While RSV seasons in 2015, 2016 and 2018 were relatively
similar, 2017 showed deviations from the overall patterns with
significantly higher RSV incidence and peak incidence 3-5 months
earlier. Concomitant circulation of RSV-A and RSV-B with an alternating
predominance of RSV-A and RSV-B strains and temporal RSV-A genotype
replacement from NA1 to ON1 were observed. Conclusion: This study
represents the first in-depth epidemiological analysis of RSV in CAF and
provides first insights into RSV burden, genetic diversity and
seasonality in the country.