A cold virus called the respiratory syncytial virus (RSV) that causes inflammation of the respiratory tract in infants, which remained dormant last year, could soon see an unusual uptick in Japan.

RSV mainly spreads via respiratory droplets when a person coughs or sneezes, as well as through direct contact with a contaminated surface — somewhat similar transmission routes to the coronavirus. Unlike that virus, however, there are no vaccines available against RSV.

RSV usually causes cold-like symptoms, including fever and a severe cough, and most people recover in a week or two, but it can lead to more serious complications, especially for infants, older adults and those with immunodeficiency or congenital heart disease.