Hand, foot, and mouth disease (HFMD) is contagious primarily during the first week of illness, often starting to be contagious a day before symptoms like rash appear. The infected person is most contagious in those early days of the illness. The blisters and rash usually dry up in about 10 days, and the person is less likely to spread the disease once the blisters are dry. However, the virus can remain in the stool for weeks or even months after symptoms have resolved, which means the virus can still be spread during that time. HFMD spreads through contact with:
- Respiratory droplets (from coughing, sneezing, or talking)
- Fluid from blisters
- Saliva and nasal secretions
- Stool, especially during diaper changes or bathroom use
- Contaminated surfaces and objects
Children are most contagious during the first week of infection, but they can shed the virus for longer periods, sometimes up to a month or more. Children with HFMD should generally stay home until the fever and pain resolve, but they may not need to stay home until the rash clears if they feel well enough otherwise. Good hand hygiene and disinfecting surfaces can help prevent the spread of HFMD. In summary:
- Contagious period starts about 1 day before symptoms
- Most contagious during the first week of illness
- Virus may still be shed for weeks after symptoms resolve
- Less contagious once blisters have dried up
- Spread via saliva, respiratory secretions, blister fluid, stool, and contaminated surfaces.
