Anticipated Increase in Acute Flaccid Myelitis Not Seen in 2020
Cases reported in 2019 and 2020 occurred in older children, were less often associated with upper-limb involvement
THURSDAY, Nov. 4, 2021 (HealthDay News) -- In 2020, the anticipated increase in acute flaccid myelitis (AFM) was not observed, and the etiologies of AFM in 2019 and 2020 differed from 2018, according to research published in the Nov. 5 issue of the U.S. Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report.
Noting that peaks in AFM cases were observed in the United States during 2014, 2016, and 2018, Sarah Kidd, M.D., from the CDC in Atlanta, and colleagues examined whether the anticipated increase in AFM in 2020 occurred. The epidemiology of confirmed AFM cases was described since 2018 using information collected as part of national AFM surveillance.
The researchers found 238 confirmed AFM cases were reported to the CDC in 2018 compared with 47 and 32 cases in 2019 and 2020, respectively. In 2018, enterovirus D68 (EV-D68) was detected in specimens from 37 cases compared with one case and none in 2019 and 2020, respectively. Cases reported in 2019 and 2020 compared with 2018 occurred in older children and were less often associated with upper-limb involvement, febrile or respiratory prodromal illness, or cerebrospinal fluid pleocytosis.
"It is not entirely clear why AFM cases did not increase in 2020," the authors write. "Nonpharmaceutical interventions implemented during the COVID-19 pandemic (e.g., face masks, physical distancing, and reduced in-person school attendance) might have reduced transmission of EV-D68 and other enteroviruses associated with AFM."