Respiratory syncytial << sihn SIH shuhl >> virus (RSV) is a microorganism that commonly causes respiratory illness in people. Most children have been infected with RSV by the time they are 2 years old. But RSV can infect people of any age.
Symptoms of RSV infection are similar to those of the common cold. They include fever, cough, congestion, runny nose, and shortness of breath. Infants may experience fussiness and lack of appetite. People infected with RSV should rest and drink fluids. Nasal sprays and drops may be used to make breathing easier. Vaporizers or humidifiers may also relieve symptoms.
For most people, symptoms are relatively mild and go away with little or no treatment. Symptoms usually persist for 5 to 7 days. However, RSV may cause severe disease in the elderly and in infants. Individuals with weakened immune systems and patients with chronic (ongoing) diseases are also at risk of developing severe illness. Respiratory failure and even death may occur in severe cases.
RSV is highly contagious. The virus spreads easily from person to person through direct contact or when an infected person coughs or sneezes near others. The virus can also be spread through contact with unwashed hands or surfaces such as doorknobs, computer keyboards, and other frequently touched objects. In the United States, infants, toddlers, pregnant individuals, and people 60 years old and older may be vaccinated against RSV. The vaccine given during pregnancy protects babies as soon as they are born.
RSV infections in the United States are most common in the fall and winter. But in the fall and winter of 2020 and 2021, RSV infected few people. During that time, many people regularly took precautions to avoid becoming sick with COVID-19. For example, they wore face masks, washed their hands frequently, and minimized physical contact with other people. These precautions also limited the spread of RSV. The number of RSV infections rose again in 2022 as fewer people took these precautions.
In particular, unusually high numbers of infants and young children were infected with RSV in 2022. These young children had probably never before been exposed to RSV because COVID-19 precautions were in effect for most of their early life. By 2023, RSV infections occurred about as frequently as they did before 2020.
