FDA approves first RSV vaccine for pregnant people and newborns

FILE - A pregnant woman cradles her baby bump in a file image. (Photo by Marcus Brandt/picture alliance via Getty Images)

The FDA approved the first vaccine for pregnant individuals to prevent respiratory syncytial virus (RSV) infections in infants up to 6 months old.

RSV is highly contagious and is the most common cause of lower respiratory tract illness in infants in the world. It is particularly prevalent in young children, with most individuals contracting RSV by the age of 2. 

While the virus often results in cold-like symptoms in infants and young children, it can also cause serious other diseases like pneumonia and bronchiolitis. According to the CDC, RSV is the primary reason for infant hospitalization in the U.S.

The vaccine Abrysvo is administered as a single-dose injection into the muscle, and is approved for use between 32 and 36 weeks during pregnancy. The FDA had previously approved Abrysvo for people 60 years and older.

Abrysvo was evaluated in randomized, placebo-controlled clinical studies worldwide. It's been shown to effectively reduce the risk of severe lower respiratory tract disease in infants. 

In the years since the COVID-19 pandemic, health officials have reported a dangerous drop in vaccinations among young kids. Only 66.5% of children between the ages of 19 to 36 months old have received their recommended doses - the lowest since 2011.

The reasons behind the decline in vaccinations are varied, but Michigan's chief health officer said a big driver is parents struggled to keep up with the recommended shots for their kids during the pandemic.

With children heading back to school soon, the state is hoping to get as many kids inoculated as they can. 

In a study, infants whose mothers were vaccinated during pregnancy had close to 82% lower risk of severe of lower respiratory tract diseases within 90 days after birth and a 69% lower risk up to 180 days after birth. 

It was also shown to be far more effective than a placebo.

MORE: 6-year-old Macomb County boy is first child to die of RSV in Michigan as cases rise

Abrysvo is associated with common side effects such as pain at the injection site, headache, muscle pain, and nausea. 

In rare instances, a hypertensive disorder called pre-eclampsia occurred in 1.8% of pregnant individuals who received Abrysvo - compared to 1.4% of those who received a placebo.

 It is unclear whether there is a causal relationship between Abrysvo and preterm-birth.

Despite these risks, Abrysvo provides healthcare providers and pregnant individuals with an option to protect infants from pre-eclampsia, a potentially life-threatening disease.