Hand, foot, and mouth disease (HFMD) is a common illness in infants and children. It is characterized by fever, sores in the mouth, and a rash with blisters. It occurs in warmer months and is transmitted primarily between humans by direct contact with secretions from the nose and throat, saliva, fluid from blisters, or the feces of those who have HFMD.

Causes

Viruses from the group called enteroviruses cause HFMD. The most common cause is coxsackievirus A16; sometimes, HFMD is caused by enterovirus 71 or other enteroviruses. The enterovirus group includes polioviruses, coxsackieviruses, echoviruses and other enteroviruses. HFMD is often confused with foot-and-mouth disease of cattle, sheep, and swine. Although the names are similar, the two diseases are not related at all and are caused by different viruses. HFMD is moderately contagious. Infection is spread from person to person by direct contact with nose and throat discharges, saliva, fluid from blisters, or the stool of infected persons. A person is most contagious during the first week of the illness. HFMD is not transmitted to or from pets or other animals.

Risk Factors

HFMD occurs mainly in children under 10 years old, but may also occur in adults too. Everyone is at risk of infection, but not everyone who is infected becomes ill. Infants, children, and adolescents are more likely to be susceptible to infection and illness from these viruses, because they are less likely than adults to have antibodies and be immune from previous exposures to them. Infection results in immunity to the specific virus, but a second episode may occur following infection with a different member of the enterovirus group.

Because enteroviruses, including those causing HFMD, are very common, pregnant women are frequently exposed to them, especially during summer and fall months. As for any other adults, the risk of infection is higher for pregnant women who do not have antibodies from earlier exposures to these viruses, and who are exposed to young children - the primary spreaders of enteroviruses.

Most enterovirus infections during pregnancy cause mild or no illness in the mother. Although the available information is limited, currently there is no clear evidence that maternal enteroviral infection causes adverse outcomes of pregnancy such as abortion, stillbirth, or congenital defects. However, mothers infected shortly before delivery may pass the virus to the newborn. Babies born to mothers who have symptoms of enteroviral illness around the time of delivery are more likely to be infected. Most newborns infected with an enterovirus have mild illness, but, in rare cases, they may develop an overwhelming infection of many organs, including liver and heart, and die from the infection. The risk of this severe illness in newborns is higher during the first two weeks of life.

Symptoms

• Mild fever

• Poor appetite

• Malaise

• Sore throat

• Painful sores in the mouth

• Skin rash that does not itch, usually on the palms of hands and soles of feet

Diagnosis

HFMD is one of many infections that result in mouth sores. Another common cause is oral herpesvirus infection, which produces an inflammation of the mouth and gums (sometimes called stomatitis). Usually, the physician can distinguish between HFMD and other causes of mouth sores based on the age of the patient, the pattern of symptoms reported by the patient or parent, and the appearance of the rash and sores on examination. A throat swab or stool specimen may be sent to a laboratory to determine which enterovirus caused the illness. Since the testing often takes 2 to 4 weeks to obtain a final answer, the physician usually does not order these tests.

Treatment

There is no specific treatment for HFMD. Treatment is focused on relieving fever, aches, and pain associated with the illness.

Prevention

To help reduce the risk of HFMD:

• Wash your hands frequently, especially after diaper changes.

• Clean contaminated surfaces with soap and water followed by a diluted solution of chlorine-containing bleach. (Mix about 1/4 cup of bleach with one gallon water.)

• Avoid close contact with children with HFMD.

RESOURCES:

Centers for Disease Control and Prevention
http://www.cdc.gov/

National Institute of Allergy and Infectious Diseases
http://www3.niaid.nih.gov/

CANADIAN RESOURCES:

Canadian Pediatric Society
http://www.cps.ca/

Public Health Agency of Canada
http://www.phac-aspc.gc.ca/

References:

Hand-foot-and-mouth disease. DynaMed website. Available at: http://dynamed101.epnet.com/Detail.aspx?id=116931. Accessed February 28, 2007.

Hand, foot, and mouth disease. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/ncidod/dvrd/revb/enterovirus/hfhf.htm. Accessed February 28, 2007.

CDC