Acute Flaccid Myelitis in the United States, August-December 2014: Results of Nationwide Surveillance.
During late summer/fall 2014, pediatric cases of acute flaccid myelitis (AFM) occurred in the United States, coincident with a national outbreak of enterovirus D68 (EV-D68)-associated severe respiratory illness.



Clinicians and health departments reported standardized clinical, epidemiologic, and radiologic information on AFM cases to the Centers for Disease Control and Prevention (CDC), and submitted biological samples for testing. Cases were ≤21 years old, with acute onset of limb weakness 1 August-31 December 2014 and spinal magnetic resonance imaging (MRI) showing lesions predominantly restricted to gray matter.



From August through December 2014, 120 AFM cases were reported from 34 states. Median age was 7.1 years (interquartile range, 4.8-12.1 years); 59% were male. Most experienced respiratory (81%) or febrile (64%) illness before limb weakness onset. MRI abnormalities were predominantly in the cervical spinal cord (103/118). All but 1 case was hospitalized; none died. Cerebrospinal fluid (CSF) pleocytosis (>5 white blood cells/µL) was common (81%). At CDC, 1 CSF specimen was positive for EV-D68 and Epstein-Barr virus by real-time polymerase chain reaction, although the specimen had >3000 red blood cells/µL. The most common virus detected in upper respiratory tract specimens was EV-D68 (from 20%, and 47% with specimen collected ≤7 days from respiratory illness/fever onset). Continued surveillance in 2015 identified 16 AFM cases reported from 13 states.



Epidemiologic data suggest this AFM cluster was likely associated with the large outbreak of EV-D68-associated respiratory illness, although direct laboratory evidence linking AFM with EV-D68 remains inconclusive. Continued surveillance will help define the incidence, epidemiology, and etiology of AFM.
Division of High-Consequence Pathogens and Pathology, National Center for Emerging and Zoonotic Infectious Diseases.
James J
JJ
Sejvar
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Adriana S
AS
Lopez
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Margaret M
MM
Cortese
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Eyal
E
Leshem
Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins.
Daniel M
DM
Pastula
Epidemiology Division, Colorado Department of Public Health and Environment, Denver.
Lisa
L
Miller
Division of Communicable Disease Control, California Department of Public Health, Richmond.
Carol
C
Glaser
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.|Oak Ridge Institute of Science and Education, Tennessee.
Anita
A
Kambhampati
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.|Oak Ridge Institute of Science and Education, Tennessee.
Kayoko
K
Shioda
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Negar
N
Aliabadi
Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins.
Marc
M
Fischer
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Nicole
N
Gregoricus
Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins.
Robert
R
Lanciotti
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
W Allan
WA
Nix
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Senthilkumar K
SK
Sakthivel
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
D Scott
DS
Schmid
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Jane F
JF
Seward
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Suxiang
S
Tong
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
M Steven
MS
Oberste
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Mark
M
Pallansch
Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.
Daniel
D
Feikin
D000208:Acute Disease; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D030016:Enterovirus D, Human; D004769:Enterovirus Infections / Q000134:cerebrospinal fluid / Q000000981:diagnostic imaging / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009123:Muscle Hypotonia / Q000134:cerebrospinal fluid / Q000000981:diagnostic imaging / Q000453:epidemiology*; D009187:Myelitis / Q000134:cerebrospinal fluid / Q000000981:diagnostic imaging / Q000453:epidemiology*; D062486:Public Health Surveillance; D014481:United States
acute flaccid myelitis; enterovirus; limb weakness; polio; surveillance