Respiratory Syncytial Virus Infection

Respiratory syncytial virus infection is caused by RSV, a common respiratory virus that infects the nose, throat, respiratory tract and lungs and usually causes mild, cold-like symptoms. Its symptoms are not specific, which makes it difficult to tell from the common cold or other respiratory viruses such as influenza or COVID-19. It spreads in the fall and winter along with other respiratory viruses and usually peaks in December and January. Infants younger than 6 months of age and adults who are older or have certain risk factors are more likely to become very sick and need hospitalization. It can cause bronchiolitis and pneumonia, and it is the most common cause of both in children younger than 1 year of age. CDC recommends immunizations for infants, some young children and higher-risk adults.