The Facts

Hand, foot, and mouth disease (HFMD) is a viral infection that usually affects babies and children. HFMD can lead to fever, a blistering rash on the hands and feet, mouth sores, sore throat, and a poor appetite.

HFMD is contagious and often causes illness within 3 to 7 days after exposure to an infected person. Proper hand-washing, avoiding close contact, and cleaning contaminated surfaces and items can help reduce the spread of the disease.

Causes

Hand, foot, and mouth disease is caused by a group of viruses known as enteroviruses. The enteroviruses called coxsackie virus A16 and enterovirus A71 are the most common causes of HFMD. However, in some cases, other enteroviruses can also cause HFMD.

Symptoms and Complications

HFMD is highly infectious. It can spread from one person to another through direct contact with discharge from the nose and throat, saliva, infected stools, or fluid from a blister. It takes up to a week for symptoms to appear once a person is infected, though not all infected people develop symptoms.

HFMD usually begins with a low-grade fever and general fatigue. A rash of tiny, painful red spots will appear within a couple of days and will soon begin to blister and sometimes form ulcers. These spots may appear:

• inside the mouth (on the tongue, gums, or cheeks)
• on the palms of the hands or on the fingers
• on the soles of the feet or on the toes
• on the buttocks and genitals

The rash is not generally itchy and, in some cases, may develop on other parts of the body. Lymph nodes in the neck may also become swollen. The virus can cause the throat and mouth to feel sore and painful, and some children will refuse to eat due to the pain.

Rarely, dehydration may occur as the pain due to the blisters in the mouth can make drinking difficult. Infection by EV71 has been known to cause encephalitis, paralysis, or viral meningitis in rare cases.

Children and adolescents are the most commonly affected people. Adults are rarely infected, although pregnant women who have not been exposed to the virus before have a higher chance of becoming infected. Daycare centres, parks, nursery schools, and other places where children play with each other are potential sites for the infection to be transmitted from one child to another. HFMD is most common in the summer and early fall.

A pregnant woman who is infected may show mild or no signs of illness. If she is infected just before her delivery, the infection can be transmitted to the newborn resulting in only a mild illness in the baby. Rarely, multiple-organ infections occur.

During the acute phase, a person can infect others through secretions from the nose and throat. Discharge due to coughing and sneezing can cause the virus to be transmitted easily. Young children who tend to drool can also transmit the infection through their saliva.

Until the blisters dry, a person should be regarded as infectious. Fluid from the blisters contains the virus. The virus is also present in the feces for several weeks after symptoms of illness have vanished. An infected person who does not develop the illness will also have the virus present in the stools.

Making the Diagnosis

Appearance of mouth sores is a common sign of many diseases, including HFMD. Your doctor will make the diagnosis based on your age, symptoms, and a physical examination. A throat swab may be taken to exclude bacterial infections that may require antibiotics.

Treatment and Prevention

Most people who develop the illness recover in 7 to 10 days with minimal or no medical intervention. There is no specific treatment for HFMD. Medication may be given for relief from symptoms such as fever and aches.
Symptoms may be relieved by:

• acetaminophen* or other fever reducers
• topical anesthetics to minimize the pain caused by the blisters

Children may not want to eat or drink because they find it difficult to swallow. Drinking enough fluids is vital to prevent dehydration. Children might refuse juices since the acidity can cause irritation of the blisters. Salty foods may also cause irritation. Ice cream, cold milk, or yogurt (including frozen yogurt) can provide nutrition and fluids as they are easier to swallow and do not irritate the blisters.

A salt water rinse may help soothe the mouth and throat. To make this mouth rinse, mix ½ tsp (2.5 mL) of salt with one cup (250 mL) of warm water. It is important to keep up with oral hygiene using a soft toothbrush.

The blisters generally heal by themselves. Avoid popping the blisters. Also, contact with the fluid from the blisters increase the chance of infection for those around you. It is best to leave the blisters alone.

If your child has any of the symptoms below, contact your doctor immediately.

• signs of dehydration (dry mouth, listlessness, weight loss, no urine for 10 to 12 hours)
• stiff neck
• pain in the back, legs, and arms
• convulsions
• persistent headache

Although the infection is not preventable, maintaining good hygiene can minimize the risk of infection. Some things you can do include:

• Wash your hands frequently – it is especially important to wash your hands thoroughly after changing your baby's diaper as the virus is transmitted through stools.
• Clean and disinfect any contaminated surfaces and soiled items.
• Avoid close contact with an infected person.

Most agree it is better to isolate those with weeping lesions and blisters, and children who tend to drool should also be kept away from healthy children.
In general, all children with viral infections should not attend school or daycare until there has been no fever for 24 hours. This generally means that the infection is no longer actively multiplying in the body and infectiousness of secretions is therefore minimal.