Clinical and laboratory data have been updated for cases that met the clinical criterion for acute flaccid myelitis (AFM) in the United States during 2018, according to a Vital Signs report published in the July 9 early-release issue of the U.S. Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.
Adriana Lopez, M.H.S., from the CDC in Atlanta, and colleagues updated data for individuals who met the clinical criterion for AFM with onset in 2018 that were submitted to the CDC for classification of illness. For persons meeting the clinical criterion, enterovirus/rhinovirus (EV/RV) testing was performed.
The researchers found that among 374 reported cases of AFM from January through December 2018, 62, 7, and 31 percent of cases were classified as confirmed, probable, and non-AFM, respectively. The median ages of patients were 5.3, 2.9, and 8.8 years for confirmed, probable, and non-AFM cases, respectively. In 44 percent of confirmed cases, multiple EV/RV types were identified in laboratory testing, mainly in respiratory and stool specimens. The interval from limb weakness onset to specimen collection varied from two to seven days among confirmed cases, depending on the specimen type. During 2018, the interval from onset of limb weakness until reporting to the CDC varied from 18 to 36 days.
“Ongoing national AFM surveillance will provide an important bridge between research and public health response and will be critical for the development of optimal treatment and prevention recommendations,” the authors write.