Hand, foot, and mouth disease (HFMD) is a common viral illness that mainly affects children under five, though adults can get it too. It causes fever, painful mouth sores, and a distinctive rash on the hands and feet. The illness is typically mild and resolves on its own within 7 to 10 days, but it spreads easily and can make eating and drinking uncomfortable, especially for young children.
What Causes It
HFMD is caused by a group of viruses called enteroviruses. The most common culprit is coxsackievirus A16, though other strains in the same family can also trigger it. These viruses circulate year-round but peak in summer and early fall in temperate climates. Getting infected with one strain doesn’t protect you from all the others, which is why some children get HFMD more than once.
How Symptoms Develop
Symptoms typically appear 3 to 5 days after a child catches the virus. The illness usually starts with a fever and general flu-like feelings: sore throat, fatigue, and reduced appetite. Within a day or two of the fever, mouth sores appear. These start as small red spots on the tongue and inside the cheeks, then blister and become painful.
A skin rash follows shortly after. It shows up on the palms of the hands and soles of the feet as flat or slightly raised red spots that sometimes blister. The rash can also spread to the buttocks, legs, and arms. Unlike many other rashes, it tends to be more annoying than itchy. The blisters typically dry up and fade within a week, and the skin heals without scarring.
Some children lose a fingernail or toenail a few weeks after the illness. This looks alarming but is temporary. The nail grows back normally.
How It Spreads
HFMD is highly contagious and spreads through several routes:
- Respiratory droplets released when an infected person coughs, sneezes, or talks
- Direct contact with fluid from blisters
- Fecal-oral contact, often through diaper changes or shared surfaces
- Contaminated objects like toys, doorknobs, or shared cups
People are most contagious during the first week of illness. However, the virus can continue shedding in stool for days or even weeks after symptoms resolve. Some people spread the virus without ever developing symptoms at all, which is part of why outbreaks move so quickly through daycare centers and preschools.
Can Adults Get It
Yes. Adults are less likely to catch HFMD because most have built up some immunity from childhood exposures, but it does happen. Adult cases can range from no symptoms at all to the full set of fever, mouth sores, and rash. Some adults report that their symptoms feel more intense than what their children experienced, though the illness still resolves on its own.
Pregnant women should be cautious. Infection during pregnancy has been linked to miscarriage, stillbirth, and in rare cases, severe illness in newborns if the mother contracts the virus close to delivery. Avoiding close contact with infected children and practicing careful hand hygiene reduces the risk.
How It’s Diagnosed
Doctors typically diagnose HFMD by looking at the pattern of symptoms: the combination of fever, mouth sores, and rash in characteristic locations is distinctive enough that lab tests are rarely needed. A throat swab or stool sample can confirm the specific virus, but this is usually reserved for unusual or severe cases.
Managing Symptoms at Home
There is no antiviral treatment for HFMD. The illness runs its course, and care focuses on keeping your child comfortable and hydrated. Over-the-counter pain relievers like acetaminophen (Tylenol) or ibuprofen (Advil) help with fever and general discomfort. Never give aspirin to children, as it’s linked to a rare but serious condition called Reye’s syndrome.
Mouth sores are often the hardest part. They can make eating and drinking painful, which raises the risk of dehydration in young children. A few strategies help:
- Cold foods and drinks: ice pops, ice chips, ice cream, and cold water soothe inflamed tissue
- Soft foods: anything that doesn’t require much chewing is easier to tolerate
- Warm salt water rinses: for children old enough to swish and spit without swallowing, rinsing several times a day can ease pain and swelling
- Avoid acidic foods: citrus fruits, fruit juices, and soda sting open sores and make the pain worse
Topical oral anesthetics in sprays or lozenges can numb mouth sores temporarily. Lozenges are a choking hazard for children under four, and throat sprays containing benzocaine should not be used in children under two.
Returning to School or Daycare
There’s no single national rule for when a child can go back. The CDC recommends that schools develop their own policies based on pathogen-specific guidance. In practice, most daycares and pediatricians follow a general approach: children can return once their fever has been gone for at least 24 hours without medication and the blisters have dried. Keep in mind that the virus still sheds in stool for weeks, so thorough handwashing after bathroom trips and diaper changes remains important even after your child seems fully recovered.
Rare but Serious Complications
The vast majority of HFMD cases are mild. Dehydration is the most common complication, especially in toddlers who refuse to drink because of mouth pain. Watch for signs like fewer wet diapers, dry lips, crying without tears, or unusual drowsiness.
In very rare cases, certain enterovirus strains can cause viral meningitis (inflammation of the membranes surrounding the brain and spinal cord) or encephalitis (brain inflammation). These complications are far more common with enterovirus 71 than with coxsackievirus A16. Persistent high fever, severe headache, stiff neck, or unusual confusion warrants immediate medical attention.
Preventing the Spread
No vaccine exists for HFMD. Prevention comes down to basic hygiene. Wash hands thoroughly with soap and water after diaper changes, bathroom visits, and before preparing food. Clean and disinfect frequently touched surfaces and shared toys, especially during outbreaks. Avoid close contact like kissing, hugging, or sharing utensils with someone who’s sick. Because the virus can spread before symptoms even appear, these habits matter most during peak season and whenever cases are circulating in your community.