What is RSV season?
Last updated September 3, 2026.
RSV circulates on roughly the flu's clock - arrives in fall, peaks in winter, fades by spring. For most healthy adults it is a bad cold. The danger concentrates at the ends of life: RSV is the commonest cause of infant hospitalization (warning signs: fast breathing, poor feeding, unusual tiredness), and in adults 75+ - or 50 to 74 with heart, lung, or immune conditions - it can become pneumonia. Prevention targets those groups, per the CDC: a maternal vaccine during pregnancy, an infant antibody shot after birth, and an RSV vaccine for all adults 75+ and at-risk adults 50-74. The seasonal behaviors are the flu set: hand washing, sick visitors kept from newborns, and no toughing out breathing trouble. Pymander is a free AI doctor, 24/7 by text, and can help you judge a winter cough.
What to do
- 75+ or 50+ with heart/lung/immune risks? Ask about the RSV shot.
- Pregnant or new parent? Ask about the two infant protections.
- Winter breathing trouble is not a cold: get it checked.
- Keep coughs away from newborns: mild for you, serious for them.
Related questions
- When is flu season?
- What vaccines do adults need?
- Do I need a COVID booster this year?
- Can I use an online doctor for my elderly parent?