The U.S. Food and Drug Administration has approved the first vaccine to protect infants from the respiratory syncytial virus, or RSV.

The single-dose Abrysvo vaccine, made by Pfizer, is designed to be administered to mothers in the 32nd – 36th weeks of pregnancy to provide protection for infants in their first six months of life. The approval comes on the heels of the FDA approving Abrysvo for use in individuals ages 60 and older.

“RSV is a common cause of illness in children, and infants are among those at highest risk for severe disease, which can lead to hospitalization,” Peter Marks, M.D., Ph.D., director of the FDA’s Center for Biologics Evaluation and Research, said in a statement. “This approval provides an option for healthcare providers and pregnant individuals to protect infants from this potentially life-threatening disease.”

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RSV is the most frequent cause of lower respiratory tract illness in infants worldwide and, while in most cases it causes no more than cold-like symptoms, it can also lead to pneumonia and bronchiolitis, or swelling of the small airway passages in the lungs, for others. Risk for RSV is highest during the first year of life and is the leading cause of infant hospitalizations in the U.S., according to the Centers for Disease Control and Prevention.

According to the FDA, clinical studies showed the drug reduced the risk of severe RSV by 82% within 90 days of birth and 69% within 180 days of birth. The most common side effects were pain at the injection site, headache, muscle pain and nausea, the FDA said.

Pending recommendation by the CDC, Pfizer said it hopes the vaccine will be available to the public by the end of October or the beginning of November.