How long am I contagious with RSV?
Last updated September 3, 2026.
Most people spread RSV for 3 to 8 days, starting a day or two before symptoms; some infants and immunocompromised people can shed it for up to 4 weeks. It moves through droplets, direct contact, and surfaces, where the virus survives for hours. The return-to-normal rule matches the CDC's general respiratory guidance: back to activities when symptoms are improving and you have been fever-free 24 hours without medication, with added precautions for a few days after. Protection priorities: young infants (RSV is the top cause of infant hospitalization), premature babies, older adults, and the immunocompromised, so skip visiting them until clearly recovered. Routine RSV has no antiviral; treatment is fluids, fever management, and watching the breathing. Emergency signs, especially in children: fast or labored breathing, bluish lips or face, and signs of dehydration like very few wet diapers.
What to do
- Typical window: 3 to 8 days, starting before symptoms.
- Long tail: infants and immunocompromised up to 4 weeks.
- Return rule: improving plus 24 hours fever-free without medication.
- Protect infants hardest: RSV is the leading cause of infant hospitalization.
- Emergency signs: labored breathing, blue lips, dehydration.
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