Different meteorological parameters influence metapneumovirus and respiratory syncytial virus activity.

BACKGROUND: Both human metapneumovirus (hMPV) and respiratory syncytial virus (RSV) cause epidemics during the cold season in temperate climates. OBJECTIVES: The purpose of this study was to find out whether climatic factors are associated with RSV and hMPV epidemics. STUDY DESIGN: Our study was based on data from 4300 patients admitted to the Dijon University Hospital for acute respiratory infection (ARI) over three winter seasons chosen for their dissimilar meteorological and virological patterns. Cases of hMPV and RSV were correlated with meteorological parameters recorded in the Dijon area. The relationship between virus data and local meteorological conditions was analyzed by univariate and multivariate negative binomial regression analysis. RESULTS: RSV detection was inversely associated with temperature and positively with relative humidity and air pressure, whereas hMPV was inversely associated with temperature and positively with wind speed. CONCLUSIONS: The association among meteorological variables and weekly ARIs cases due to RSV and hMPV demonstrated the relevance of climate factors as contributors to both hMPV and RSV activities. Meteorological drivers of RSV and hMPV epidemics are different. Low temperatures influence both hMPV and RSV activity. Relative humidity is an important predictor of RSV activity, but it does not influence hMPV activity.