Request for information about acute encephalopathy associated with influenza virus infection in U.S. children

Morbidity and Mortality Weekly Report, Dec 12, 2003

Since the mid-1990s, several hundred cases of acute encephalopathy have been reported in Japanese children with influenza virus infection (1,2). These cases have been characterized by fever and rapid onset of encephalopathy, resulting in a high frequency of neurologic sequelae and mortality. The majority of the children have had laboratory-confirmed evidence of influenza.

Reports of influenza-associated encephalopathy have been uncommon in the United States (3,4). To determine if a similar pattern is occurring in the United States, CDC is requesting information on any case meeting certain criteria. The criteria include a person aged <18 years with altered mental status or personality change lasting >24 hours and occurring within 5 days of onset of an acute febrile respiratory illness, laboratory or rapid diagnostic test evidence of acute influenza virus infection associated with the respiratory illness, and diagnosis of the condition in the United States. Cases meeting these criteria should be reported to CDC (telephone, 404-639-0277 of 404-639-2893; fax, 404-639-3866; of e-mail, tmu0@cdc.gov or nib9@cdc.gov).

References

(1.) Morishima T, Togashi T, Yokata S, et al. Encephaliris and encephalopathy associated with an influenza epidemic in Japan. Clin Infect Dis 2002;35:512-7.

(2.) Sugaya N. Influenza-associated encephalopathy in Japan. Semin Pediatr Infect Dis 2002;13:79-84.

(3.) McCullers JA, Facchini S, Chesney PJ, Webster RG. Influenza B virus encephalitis. Clin Infect Dis 1999;28:898-900.

(4.) Straumanis JP, Tapia MD, King JC. Influenza B infection associated with encephalitis: treatment with oseltamivir. Pediatr Infect Dis J 2002;21:173 5.