Press Release

Update: Enterovirus Outbreak in Taiwan

CDC has assisted the Ministry of Health (MOH), Taiwan, Republic of China, in the investigation of a recent outbreak of viral illness among infants and young children. Since April 1998, at least 50,000 children have contracted hand, foot and mouth disease (HFMD), and about 320 children have been hospitalized with HFMD complicated by other symptoms, including viral meningitis or encephalitis. In addition, at least 55 children, most younger than 3 years old, have had a short illness with fever (2 to 4 days' duration), followed by a sudden deterioration in their condition, and they died within 12 to 24 hours. Many of the children who have died had meningitis or encephalitis, and some had rash and mouth ulcers. The outbreak of HFMD occurred in all areas of the island. Fatal cases have also occurred in many but not all areas of Taiwan. Enteroviruses have been isolated from children with HFMD, meningitis or encephalitis, and fatal disease. In particular, enterovirus 71 (EV71) has been identified most often in HFMD cases. The investigation of EV71 involvement among the fatal cases is continuing. There have been no further reports of outbreak-associated deaths since July 11 in Taiwan, suggesting that the outbreak is ending. Additionally, reports of HFMD have decreased 90%.

HFMD is a common childhood rash illness that occurs worldwide, both as individual cases and in outbreaks. It is usually a mild illness characterized by fever, sores in the mouth, and a rash with blisters. The illness usually begins with a mild fever and malaise or fussiness in infants. One or 2 days after the fever begins, sores develop in the mouth. The sores begin as small red spots that blister and then often become ulcers. The skin rash develops over 1 to 2 days, with flat or raised red spots, some with blisters. The rash is usually located on the palms of the hands and soles of the feet. It may also appear on the buttocks. A person with HFMD may have only the rash or the mouth ulcers.

The most common cause of HFMD is infection with coxsackievirus A16 (CA16), a member of the enterovirus group of viruses. Usually, there are no complications of HFMD caused by CA16 infection, although viral meningitis may occur occasionally. A second, less common cause of HFMD is infection with EV71. In addition to HFMD, EV71 may also cause viral meningitis, encephalitis, or a poliomyelitis-like paralysis. EV71 meningitis or encephalitis may occasionally be fatal. HFMD is moderately contagious. The enteroviruses that cause HFMD are not spread by airborne transmission and are usually not spread by contaminated food or water. Rather, infection is spread from person to person by direct contact with nose and throat secretions (e.g., nasal mucus or saliva) or the stool of infected persons. A person is most contagious during the first week of the illness. The usual period from infection to onset of symptoms is 3 to 7 days.

There is some risk that international travelers in Taiwan may be exposed to and possibly infected by the virus causing HFMD, but the risk of death associated with the outbreak in Taiwan is very small. The greatest risk of death is for Taiwanese children younger than 3 years old: the death rate for this group since the outbreak began in April 1998 has been approximately 1 per 10,000. This rate is comparable to the annual death rate from motor vehicle accidents in the USA, which is about 2 per 10,000 persons among persons of all ages. The risk of death among older Taiwanese children is substantially lower, and no adults have been reported to have died with this clinical syndrome. Risk also seems to differ by geographic region: most of the fatal cases have occurred in central and northern Taiwan. No deaths have been reported among children or adults from other countries visiting or living in Taiwan or in contacts of person coming from Taiwan.

Persons in Taiwan may decrease their risk of getting an enterovirus (including EV71) infection by avoiding prolonged, direct contact with persons who have HFMD and by observing the following hygienic measures: frequent handwashing, especially after diaper changes; disinfection of contaminated surfaces by household disinfectants such as bleach (1/4 cup per gallon of water) or rubbing alcohol (70% isopropyl); and washing soiled articles of clothing. Children are often excluded from child care programs, schools, or other group settings during the first few days of the illness. These measures may reduce the spread of infection, but they will not completely interrupt it.

Currently, no specific treatment is licensed for CA16, EV71, or other enterovirus infections. Treatment of mild cases of HFMD is symptomatic, given to provide relief from fever, aches, or pain from mouth ulcers. Children ill with meningitis or encephalitis are usually hospitalized.

The current HFMD outbreak among infants and children in Taiwan is not related to the foot and mouth disease outbreak that occurred among swine in Taiwan in 1997. Although the names of the two diseases are similar, they are not related and are caused by different viruses.

All recipient health departments, travel agencies, airlines and shipping companies are requested to notify prospective travelers of these recommendations. For future updates of this advisory, you may either call the CDC Fax Information Service at 1­888­232­3299 and request document number 300005 or go to the CDC website http://www.cdc.gov/ and select Travelers' Health.

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U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES