Hand, foot, and mouth disease (HFMD) is a common viral infection that causes sores in the mouth and a rash on the hands and feet. It mostly affects children under 5, but anyone can get it. The illness is usually mild, and nearly all people recover in 7 to 10 days with minimal or no medical treatment.
What Causes It
HFMD is caused by viruses in the enterovirus family. In the United States, the most common culprit is coxsackievirus A16. Another strain, coxsackievirus A6, can also cause the disease and tends to produce more severe symptoms, including a more widespread rash and higher fevers.
A different strain called enterovirus 71 (EV-A71) is more common in East and Southeast Asia and has been linked to outbreaks there. EV-A71 is notable because, although rare, it can cause serious neurological complications like brain swelling. There is currently no vaccine available in the United States to prevent any of these infections.
How It Spreads
The virus spreads through close personal contact, and children in daycare or school settings are especially vulnerable. The main routes of transmission include contact with fluid from the blisters, saliva, nasal mucus, and stool. A child who touches a contaminated toy and then puts their hands near their mouth can easily pick it up. Coughing and sneezing also spread the virus through respiratory droplets.
One tricky aspect of HFMD is that the virus can remain in stool for weeks after symptoms have cleared. This means a child who feels perfectly fine can still pass the infection to others, which is one reason outbreaks tend to cycle through entire classrooms.
Symptoms and What to Expect
The illness typically starts with a fever, reduced appetite, sore throat, and a general feeling of being unwell. Within a day or two, small painful sores develop inside the mouth, usually on the tongue, gums, and inner cheeks. These mouth sores (sometimes called herpangina when they cluster in the back of the throat) can make eating and drinking uncomfortable, especially for young children.
A skin rash follows, appearing as flat red spots or small blisters on the palms of the hands, soles of the feet, and sometimes the buttocks or legs. The rash itself isn’t usually itchy, but the blisters can be tender. In cases caused by coxsackievirus A6, the rash may be more extensive, covering larger areas of the body and producing bigger blisters.
Not everyone gets every symptom. Some children develop only mouth sores, others get only the rash, and some have such a mild case that they never seem noticeably sick at all.
HFMD in Adults
Although HFMD is most common in young children, adults can and do catch it, often from their own kids. Adults may experience the same mouth sores, rash, and fever, though some get through it with milder symptoms or no symptoms at all. The recovery timeline is similar: 7 to 10 days in most cases. The biggest complaint from adults tends to be the mouth sores, which can be painful enough to interfere with eating for several days.
Managing Symptoms at Home
There’s no antiviral medication for HFMD. Treatment focuses on keeping your child comfortable and hydrated while the virus runs its course.
Mouth sores are the biggest obstacle because they can make children refuse to eat or drink. Over-the-counter pain relievers like acetaminophen or ibuprofen help with both fever and mouth pain. For toddlers and older kids, soft, cool foods work best: yogurt, pudding, pasta, smoothies, and ice pops. Cold foods in particular can soothe sore spots. Avoid anything acidic or salty, like citrus juice or chips, which will sting.
Dehydration is the main concern to watch for. Young children who won’t drink because of mouth pain can become dehydrated quickly. Warning signs include no wet diaper in six to eight hours, dry lips and mouth, no tears when crying, and dark yellow urine. If you notice these signs, contact your child’s healthcare provider.
How Long It’s Contagious
Children with HFMD are most contagious during the first week of illness, particularly while they have a fever and active blisters. However, because the virus lingers in stool for weeks afterward, perfect containment is difficult. Most daycare centers allow children to return once they’re fever-free and the blisters have dried, but policies vary.
Frequent handwashing is the single most effective way to limit spread, especially after diaper changes and before preparing food. Cleaning and disinfecting shared surfaces and toys also helps. The CDC recommends cleaning with soap and water first, then applying a diluted bleach solution or an EPA-registered disinfectant. The surface needs to stay wet for the full contact time listed on the product label to effectively kill the virus.
Possible Complications
Serious complications from HFMD are rare, but they do happen. Dehydration from refusing to drink is the most common issue, especially in very young children. In some cases, children lose one or more fingernails or toenails a few weeks after the illness, a condition called onychomadesis. It looks alarming, but the nails grow back on their own.
The more concerning complications are neurological and are primarily associated with the EV-A71 strain. These can include viral meningitis (inflammation of the membranes surrounding the brain and spinal cord) and, very rarely, encephalitis (swelling of the brain itself). Signs that warrant immediate medical attention include a stiff neck, persistent high fever, seizures, or unusual lethargy and confusion. These outcomes are uncommon, particularly in the United States, where EV-A71 is not the dominant strain.
How It’s Diagnosed
Doctors typically diagnose HFMD based on the child’s age, symptoms, and the distinctive pattern of mouth sores plus rash on the hands and feet. The combination is recognizable enough that lab tests aren’t usually needed. In rare cases where a more serious infection is suspected, or during an outbreak investigation, a throat swab or stool sample can confirm which specific virus is involved.