22 September 2023
Nirsevimab is a monoclonal antibody with activity against Respiratory Syncytial Virus (RSV). Monoclonal antibodies are laboratory-made proteins that mimic the immune system’s ability to fight off harmful pathogens such as viruses. One dose of nirsevimab administered to infants as a single intramuscular injection prior to, or during RSV season, may provide protection during the RSV season. Young infants have the highest incidence of severe disease, peaking at 1–3 months of age.