Updated: Aug 23
Respiratory Syncytial Virus (RSV) is a common cause of respiratory tract infections in children and adults. Most adults with RSV infection are either asymptomatic or have mild cold-like symptoms that involve the upper respiratory system and resolve in 1-2 weeks. However, older age, underlying cardiopulmonary or metabolic disease, and immunocompromise increase the risk of developing lower respiratory tract disease, which may lead to shortness of breath, wheezing, decreased oxygen saturation, the need for supplemental oxygen, and may result in hospitalization for the management of respiratory distress or the decompensation of their underlying condition. In the USA, it is estimated that between 60,000 and 160,000 older adults are hospitalized, and between 6,000 to 10,000 die from RSV infection per year. Prevention is the best defense against RSV since there is no direct treatment for RSV, and patients can only be managed with supportive care (hydration, rest, and symptom relief) and with steroids, respiratory therapy, and oxygen in more severe cases. Very young children are also at a very high risk of severe RSV, but a detailed discussion of this age group is outside the scope of this article.
RSV season starts in late fall, peaks in winter, and extends into early spring, and transmission involves contact with respiratory secretions, fomites, and large respiratory droplets. As with influenza, infections can be mitigated by avoiding sick people, cleaning high-touch surfaces, washing hands before touching the face, and using face coverings. There is a large overlap in symptoms among different viral respiratory infections; hence multi-virus viral studies (e.g., PCR) should be used to identify the causative virus to guide therapy. Immunization against respiratory virus pathogens is also a very important preventative measure for everyone eligible to receive the vaccines, especially for any high-risk individual or anyone that comes into contact with them. This fall, vaccines that protect against RSV join the armamentarium that includes seasonal flu and COVID vaccines.
The RSV vaccines are currently approved for individuals of 60 years of age and older and should be considered for people at higher risk of a complicated RSV course. The vaccine provides moderate to high protection against the development of lower respiratory symptoms and other complications for at least a few years (studies on the duration of protection are ongoing). Side effects of the vaccination are similar to those seen with other immunizations: local reactions at the administration site, muscle and joint pain, and fatigue; there were six cases of inflammatory neurological conditions in vaccine trials, the incidence of which is being monitored. The vaccine can be administered at the same office visit as other vaccines and should be given as soon as commercially available and before the start of the fall respiratory virus season.
The following vaccines have been approved to date:
Arexvy (GSK) a single dose in adults 60+ lowered the risk of symptomatic illness by 83% and of severe illness by 94%, after 14 months protection fell to 77% and 85% respectively.
Abrysvo (Prizer) a single dose vaccine in adults 60+ lowered risk of symptomatic illness by as much as 86% with a decrease to 79% at around 18 months. This vaccine was also just approved for pregnant women between 32 and 36 weeks of pregnancy to protect their infants from the virus in the first 6 months of their life, when they are at particular risk of severe RSV disease. The vaccine decreased risk of these conditions by 82%. There was a slightly increased incidence of preeclampsia, preterm birth, low birth weight, and jaundice in the vaccine group compared to placebo.
Nirsevimab (Beyfortus™, AstraZeneca + Sanofi) is a monoclonal antibody to help prevent a serious lung disease newborns and babies under 1 year of age born during or entering their first RSV season and in children up to 24 months of age who remain at risk of severe RSV disease through their second RSV season. It is administered as a single injection and functions similarly to a vaccine by providing immunity.
** Updated: 8/23/23 **