Respiratory syncytial virus
Respiratory syncytial virus (RSV) is a major cause of respiratory illness in young children. RSV causes infection of the lungs and breathing passages. In adults, it may only produce symptoms of a common cold, such as a stuffy or runny nose, sore throat, mild headache, cough, fever, and a general feeling of being ill. But RSV infections can lead to other more serious illnesses in premature babies and kids with diseases that affect the lungs, heart, or immune system.
RSV is highly contagious, and can be spread through droplets containing the virus when a person coughs or sneezes. The virus can also live on surfaces such as countertops or doorknobs, and on hands and clothing. RSV can be easily spread when a person touches an object or surface contaminated with the virus. The infection can spread rapidly through schools and child-care centers. Infants often get it when older kids carry the virus home from school and pass it to them. Almost all kids are infected with RSV at least once by the time they are 2 years old.
RSV infections often occur in epidemics that last from late fall through early spring. Respiratory illness caused by RSV — such as bronchiolitis or pneumonia — usually lasts about a week, but some cases may last several weeks. Doctors typically diagnose RSV by taking a medical history and doing a physical exam. Generally, in healthy kids, it's not necessary to distinguish RSV from a common cold. But in cases where a child has other health conditions, a doctor might want to make a specific diagnosis. RSV is typically identified in nasal secretions, which can be collected either with a cotton swab or by suction through a bulb syringe.