Definition Hand, foot and mouth (HFM) disease is a viral infection with a characteristic rash. It usually occurs in young children.
What is going on in the body? HFM disease produces a rash on the palms of the hands, the soles of the feet and the mucous membranes of the mouth. It has no relation to foot and mouth disease, a viral infection often found in farm animals. Most of the time, HFM disease is caused by the coxsackie virus A16. This is a member of a viral subgroup known as enteroviruses. Enteroviral infections are more common in the summer and autumn months. The viruses infect humans only, and are passed in faeces. The disease is often spread when a person with contaminated hands touches food or objects, such as dummies, that are put into the child's mouth. This faecal-oral route explains why this type of virus is common in toddlers and young children. Less commonly, some enteroviruses are passed through respiratory secretions.
What are the signs and symptoms of the disease? Symptoms of HFM include:
rash. This appears as small red dots and small blisters on the palms of the hands and the soles of the feet. It also occurs on the sides of the fingers and toes, and tops of the hands and feet. The rash can form small mouth ulcers on the child's tongue and mucous membranes. Rarely, the rash will appear on the upper arms, legs, buttocks and genitals. The blisters are about 1/4 inch in diameter. They last about 7 to 10 days before drying up.
fever. This is usually the first symptom of the disease. It comes on 3 to 6 days after the child is exposed. The level of fever ranges from about 38 to 39 degrees Celsius.
HFM disease is usually a minor illness with only a few days of fever and relatively mild symptoms. Rarely, a severe form of HFM disease caused by enterovirus 71 can involve the brain. Viral meningitis, encephalitis or paralysis can result.
What are the causes and risks of the disease? Factors that put a person at risk for the disease include:
poor sanitation
crowded living conditions
age less than five years
What can be done to prevent the disease? HFM disease is a contagious infection. Careful hand washing after using the toilet or changing a nappy can decrease the spread of the infection. Hands should also be washed well before food preparation. Children and toddlers should be taught good hygiene. Children with HFM disease are contagious for about a week. They should be kept out of day care or school until the fever is gone and the mouth ulcers have healed.
How is the disease diagnosed? HFM disease is diagnosed by observing the characteristic rash. There are no commonly used tests to identify the virus. There are several other viral infections that are sometimes confused with HFM disease. Chickenpox, also known as varicella, also has a blister-like rash. However, the chickenpox rash is more wide spread. Also, the chickenpox blisters are larger and heal by crusting over rather than drying up.
Herpes simplex type1 produces mouth sores but these are often painful ulcers that are accompanied by swollen lymph glands in the neck and a high fever. Children with herpes simplex, especially with the first episode, are sicker than those with HFM disease. Also, herpes does not cause a rash on other parts of the body.
Two other disease, herpangina and aphthous stomatitis, are also characterised by sores in throat and mouth but neither produce rashes on the extremities. Also, aphthous stomatitis tends to occur in older children and adults.
What are the long-term effects of the disease? HFM disease is a mild illness without major long-term effects. If the brain is affected in the severe form of the virus, serious neurological or developmental problems can result.
What are the risks to others? HFM is a contagious disease that is easily passed from one person to another.
What are the treatments for the disease? Since HFM disease is caused by a virus, antibiotics are of no use. There is no anti-viral medication that is effective. Since it is a mild illness, treating symptoms to make the child more comfortable is usually all that is necessary.
Sucking on ice chips or using simple analgesias such as paracetamol can help with fever and flu-like symptoms. The mouth ulcers will be less painful if the child avoids:
citrus fruits and fruit drinks such as orange juice
salty foods or beverages such as Gatorade
spicy foods
foods that require a lot of chewing
Cold drinks, Popsicles and sherbet are often well liked and well tolerated. The person should drink plenty of fluids, and rinse the mouth with warm water after meals.
What are the side effects of the treatments? Side effects to paracetamol include stomach upset or allergic reactions. Any unusual side effects after taking either medication should be reported to the doctor.
What happens after treatment for the disease? Fever and discomfort usually improves in 3 to 4 days. Mouth ulcers usually improve in about 7 days and the rash on the hands and feet may last 10 days. One complication seen frequently with HFM is dehydration from refusing to drink fluids. A person should contact the doctor immediately if the child:
It is also important to contact a doctor if fluid intake is poor, mouth pain is severe, the gums are swollen and tender, or any other concerns arise.
How is the disease monitored? Usually symptoms improve with the course described. The doctor should be contacted if symptoms continue or fever lasts more than 3 days.
Author: John Wegmann, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request