Hand-foot-mouth disease, a summer infectious illness that mainly affects infants and young children, is spreading rapidly. The number of patients has risen for seven consecutive weeks, reaching about double the level seen during the same period last year.
According to the Korea Disease Control and Prevention Agency (KDCA) on Friday, the rate of suspected hand-foot-mouth disease cases at sentinel surveillance medical institutions stood at 11.2 per 1,000 outpatients in the 25th week of this year (June 14–20). After recording 0.9 in the 18th week, the figure continued to rise weekly, exceeding 10 per 1,000 for the first time this year. Compared with 5.8 in the 25th week of last year, this is roughly double the level.
Cases are particularly concentrated among infants and young children aged 5 and under, who have weaker immunity. As of the 25th week of this year, the suspected case rate for those aged 0 to 6 was 16 per 1,000.
According to Seoul National University Hospital, hand-foot-mouth disease tends to see patient numbers begin rising in May each year and peak around August.
Hand-foot-mouth disease is mainly caused by enterovirus infections such as Coxsackievirus A16 and Enterovirus A71. After an incubation period of 3 to 5 days following infection, symptoms such as mild fever, sore throat, and loss of appetite appear first.
Painful blisters and ulcers then develop inside the mouth, including on the tongue, palate, gums, and inner lips. In severe cases, the pain can make it difficult to swallow saliva, leading to excessive drooling.
Hand-foot-mouth disease is easily confused with chickenpox, but the causes and symptoms differ. Chickenpox is caused by the varicella-zoster virus, with a rash that begins on the face or torso and spreads throughout the body, progressing into blisters, pustules, and scabs accompanied by itching.
By contrast, hand-foot-mouth disease spreads through direct contact with an infected person's feces, saliva, nasal discharge, or phlegm, as well as through droplets from coughing or sneezing. In environments where shared items such as toys or playground equipment are used together, it can also easily spread through indirect contact.
Most cases recover naturally within 3 to 7 days, but caution is needed as dehydration can occur when food and fluid intake decreases due to mouth pain.
In rare cases, if high fever persists or repeated vomiting, convulsions, or reduced consciousness occur, complications such as aseptic meningitis, encephalitis, or myocarditis can develop, requiring an immediate visit to the emergency room.
Since there is no vaccine or treatment for hand-foot-mouth disease, personal hygiene management such as handwashing is the most effective prevention method. It is important to wash hands with running water and soap after going out, before and after meals, and after changing diapers, and to keep toys, doorknobs, and other items children frequently touch clean.
"When hand-foot-mouth disease is suspected or diagnosed, stopping group activities such as daycare and kindergarten until the infectiousness weakens is the most effective way to prevent the spread of infection," said Yoon Ki-wook, a professor of pediatrics at Seoul National University Hospital.
