Hand, Foot, and Mouth Disease (HFMD)

Hand, Foot, and Mouth Disease, or HFMD, is a viral infection commonly found in young children, particularly those under 5 years old. Outbreaks of this disease are often seen in places where many children gather together, such as kindergartens, daycare centers, or childcare facilities.

While most cases of HFMD are mild and resolve on their own within about 7 to 10 days, the disease spreads easily, particularly during the early stages of illness. Some children may develop mouth sores severe enough to reduce their food and fluid intake, putting them at risk of dehydration.

Understanding the symptoms, causes, transmission routes, basic care guidelines, and warning signs that warrant a doctor's visit is therefore important for parents and caregivers.

What Is Hand, Foot, and Mouth Disease?

HFMD is a viral infection caused by non-polio enteroviruses. Common causative viruses include Coxsackievirus A16 and other types of enterovirus.

The disease typically causes fever, sore throat, sores or blisters in the mouth, and a rash or blisters on the palms of the hands and soles of the feet. Some cases may also involve a rash on the buttocks, legs, or other parts of the body.

HFMD is not the same disease as foot-and-mouth disease in animals. Although the names may sound similar, they are entirely different diseases caused by different groups of viruses.

Why Is HFMD Common in Young Children?

Young children are particularly susceptible to infection because their immune systems are still developing. Children at this age also commonly put toys and objects in their mouths, share items with others, and have close contact with peers at school or daycare.

In addition, diaper changing, shared bathroom use, and incomplete handwashing can make it easier for the virus to spread. As a result, the disease often occurs in clusters or outbreaks within schools and childcare centers.

While HFMD is most common in children, adults can also become infected. Some adults may have mild symptoms or none at all, but can still spread the virus to others.

Causes of Hand, Foot, and Mouth Disease

HFMD is caused by infection with enteroviruses, most commonly Coxsackievirus A16 and Enterovirus 71, along with other types of enterovirus.

The virus can enter the body through the mouth, nose, or contact with an infected person's bodily fluids, such as saliva, nasal discharge, phlegm, fluid from blisters, or stool.

The incubation period for HFMD is generally around 3 to 6 days after exposure. Children may initially develop fever, sore throat, loss of appetite, or general discomfort before mouth sores and a rash appear.

How Does HFMD Spread?

HFMD spreads from person to person in several ways, particularly through close contact with an infected person or contaminated surfaces.

Common routes of transmission include:

• Contact with an infected person's saliva, nasal discharge, or phlegm
• Exposure to droplets from coughing, sneezing, or close conversation
• Contact with fluid from blisters or clear vesicles
• Contact with an infected person's stool, such as during diaper changes
• Sharing items such as cups, utensils, toys, handkerchiefs, or towels
• Touching contaminated surfaces such as doorknobs, tables, chairs, or toys

Infected individuals are usually most contagious during the first week of illness. However, the virus may continue to be present in stool for several weeks after symptoms improve. Hand washing and good hygiene should therefore continue even after the rash or sores begin to heal.

Symptoms of Hand, Foot, and Mouth Disease

Symptoms of HFMD can vary from person to person. Some children experience the full range of symptoms, while others may have only a mild fever and a few spots.

Commonly observed symptoms include:

• Fever
• Sore throat
• Loss of appetite or reduced food intake
• Fussiness, fatigue, or general discomfort
• Mouth sores, mouth pain, or difficulty swallowing
• Clear blisters or sores on the tongue, gums, inside of the cheeks, or back of the throat
• Rash or blisters on the palms of the hands and soles of the feet
• Possible rash on the buttocks, legs, or other parts of the body

The rash from HFMD is usually not itchy, though some cases may involve blisters or tenderness at the rash sites. Mouth sores are often the main reason children refuse to eat or drink.

In general, symptoms gradually improve within 7 to 10 days. If a child's symptoms last longer than this, or worsen, they should be seen by a doctor.

When Should You Take Your Child to See a Doctor?

Most cases of HFMD are not severe, but parents should monitor symptoms closely. A child should be seen by a doctor if any of the following occur:

• The child is younger than 6 months old
• High fever, or fever that does not go down within 3 days
• The child becomes drowsy, weak, or unresponsive
• The child drinks very little or refuses to drink fluids
• Reduced urination, dry mouth, crying without tears, or suspected dehydration
• Mouth pain so severe that the child cannot eat or drink
• Seizures
• Abnormal breathing
• Severe headache, neck stiffness, excessive vomiting, or suspected neurological symptoms
• The child has an underlying health condition or weakened immune system
• Symptoms do not improve within 10 days
• The rash shows signs of infection, such as swelling, redness, warmth, pus, or increasing pain

If severe symptoms occur, such as seizures, extreme drowsiness, difficulty breathing, or suspected severe dehydration, go to the hospital immediately.

Complications of Hand, Foot, and Mouth Disease

Complications from HFMD are uncommon but can occur, particularly in young children or those with more severe illness.

Complications to be aware of include:

• Dehydration
  • This is the most common complication, as children may refuse to drink due to painful mouth sores. If fluid intake is very low, a medical evaluation may be needed, and in some cases intravenous fluids may be required.
• Viral meningitis
  • This is uncommon but should be watched for. Symptoms may include fever, headache, neck stiffness, vomiting, or drowsiness. If suspected, a doctor should be seen promptly.
• Encephalitis
  • This is a very rare but serious complication. Symptoms may include drowsiness, seizures, weakness, or behavioral changes, and requires hospital treatment.
• Nail shedding after recovery
  • Some children may experience shedding of the fingernails or toenails some time after recovering from the illness. This usually resolves on its own, but if there is pain, swelling, redness, or suspected infection, a doctor should be consulted.

How Is HFMD Diagnosed?

Doctors generally diagnose HFMD based on the patient's symptom history, age, the appearance of the rash and mouth sores, and any history of contact with infected individuals or outbreaks at school.

Laboratory testing is generally not required in every case. However, in certain situations, such as severe symptoms, unclear presentation, suspicion of another condition, or complications, a doctor may consider additional testing as appropriate.

Treatment Approach for Hand, Foot, and Mouth Disease

There is currently no specific antiviral treatment for HFMD in typical cases. The main approach to care is managing symptoms and preventing dehydration.

Care may include:

• Ensuring the child gets adequate rest
• Encouraging frequent fluid intake to prevent dehydration
• Offering soft, easy-to-swallow foods that do not irritate mouth sores
• Avoiding spicy, sour, salty, or crunchy foods, as these may worsen mouth pain
• Using fever reducers or pain relievers as advised by a doctor or pharmacist
• Avoiding aspirin in children, as it may increase the risk of serious complications

If a child has a high fever, severe mouth pain, cannot drink fluids, or shows any unusual symptoms, they should be seen by a doctor. Medications or topical treatments for the mouth should not be used without consulting a healthcare professional.

How to Prevent Hand, Foot, and Mouth Disease

HFMD spreads easily, but the risk of transmission can be reduced through consistent good hygiene practices.

Recommended prevention measures include:

• Washing hands with soap and water for at least 20 seconds
• Washing hands after using the bathroom, after changing diapers, and after coughing, sneezing, or blowing the nose
• Washing hands before preparing food and before eating
• Teaching children not to put hands, toys, or objects in their mouths
• Cleaning toys, tables, chairs, doorknobs, and other shared surfaces
• Avoiding hugging, kissing, or sharing items with someone who is sick
• Keeping sick children away from other children as advised by a doctor, school, or public health authority
• Disposing of tissues or materials contaminated with bodily fluids appropriately
• Caregivers should wash their hands every time after contact with a child's saliva, nasal discharge, blister fluid, or stool

During outbreaks, schools and childcare centers should increase the frequency of cleaning shared areas, screen children for fever or rash, and notify parents if a case is identified in the classroom.

Summary

Hand, Foot, and Mouth Disease is a common viral infection in young children, particularly in schools and daycare settings. Common symptoms include fever, sore throat, mouth sores, and a rash or blisters on the hands, feet, or buttocks.

Most cases are mild and resolve on their own within 7 to 10 days, but dehydration should be watched for, particularly in children whose mouth sores limit fluid intake. If a child is younger than 6 months old, has a high fever, becomes drowsy, has seizures, cannot drink fluids, or does not improve within 10 days, they should be seen by a doctor.

Key prevention measures include proper handwashing, cleaning shared toys and surfaces, avoiding sharing personal items with someone who is sick, and keeping a sick child home until symptoms improve, following the guidance of a doctor or school.

References Centers for Disease Control and Prevention. About Hand, Foot, and Mouth Disease., Mayo Clinic. Hand-foot-and-mouth disease: Symptoms and causes., Cleveland Clinic. Hand, Foot and Mouth Disease.