Understanding Hand-Foot-and-Mouth Disease

A common childhood viral infection, hand-foot-and-mouth disease mainly affects children, but can also be contracted by adults of all ages. While it is generally a mild illness, its characteristic symptoms of tiny blisters on the palms of hands and the soles of the feet can be a worrisome sight. However, as Dr. Caroline Quach, Infectious Disease Specialist at The Montreal Children’s Hospital explains, there is no need to panic.

Causes:

Hand-foot-and-mouth disease is usually caused by a Coxsackievirus A16, which belongs to the Enterovirus family. Other members of the Enterovirus family may also cause hand-foot-and-mouth disease. The Enterovirus family includes over 90 different types of viruses that cause frequent illness in infants and children. The most common manifestation is fever alone. They can also cause sore throats with respiratory symptoms, hand-foot-and-mouth disease, viral meningitis, gastroenteritis, conjunctivitis, and infection of the heart. Most outbreaks occur during the summer and fall. “As is the case with many other viruses, a child will develop protection against the disease once he or she has contracted it, but only for this particular virus. As there are over 90 types, similar symptoms may occur more than once,” Dr. Quach explains.

Symptoms:

Some infections can be asymptomatic. In other cases, the following signs may be present:

A rash (vesicles or pustules) may also occur on the hands and fingers, the soles of the feet and buttocks. Most vesicles will disappear in about one week.
Blisters may also form in the mouth, making it sometimes difficult for a child to eat or drink.
Common cold symptoms may also be present, and can include fever, sore throat, runny nose and cough.
Symptoms may vary; in some children all symptoms may be present, while others will only exhibit one or two.

Incubation and contagion periods:

The typical incubation period of the virus varies from 3 to 6 days, according to the Infection Control Guidelines for Daycare and Child Care Centres outlined by the Québec Ministry of Health and Social Services.

Infected children and adults will be most contagious during the acute phase of illness. However, the virus may persist in stools 8 to 12 weeks after the infection.

Everyone is susceptible to the infection but children aged less than 10 years of age are more often infected. There is no need to exclude a child from school or daycare if the child has hand-foot-and mouth disease. However, these institutions may decide to inform parents about the fact that their children may have come into contact with an infected child for information purposes. It is not necessary to exclude a child with symptoms of hand-foot and mouth disease from daycare if the child's health status allows him or her to participate fully in the daycare's activities, such as play time and eating with other children.

Transmission:

Children and adults may contract the virus in the following ways:

By direct contact
Indirect contact (by touching surfaces that have been infected)

Risks:

According to Dr. Quach, hand-foot-and-mouth disease is usually considered to be mild. However, in cases of patients who are immunosuppressed, for example, in individuals with deficit in antibodies, persistent infection may occur. It is therefore important to seek medical attention if a child is particularly vulnerable to infection because of a known medical condition.

In addition, pregnant women who contract the virus may pass the infection to the fetus in some cases, causing infection of the heart in some babies.

Treatment:

There is no vaccine or treatment for hand-foot-and-mouth disease, says Dr. Quach, who recommends letting the virus run its course.

References:

Infection Control Guidelines for Daycare and Child Care Centres by the Québec Ministry of Health and Social Services [1]

American Academy of Pediatrics [2]

Public Health Agency of Canada [3]