Outbreak of neurologic enterovirus type 71 disease: a diagnostic challenge.
BACKGROUND
Similar to poliovirus, enterovirus type 71 (EV71) causes severe disease, including aseptic meningitis, encephalitis, acute flaccid paralysis, and acute cardiopulmonary dysfunction. Large epidemics of EV71 infection have been reported worldwide.


METHODS
After recognition of a cluster of cases of EV71 disease, we reviewed records of patients with EV71 disease who required hospitalization at The Children's Hospital in Denver, Colorado, from 2003 through 2005. The presence of enterovirus was detected by reverse-transcriptase polymerase chain reaction (PCR) and/or viral culture of specimens from multiple sources, and the virus was typed as EV71 using genetic sequencing.


RESULTS
Eight cases of EV71 disease were identified in both 2003 and 2005. Fifty-six percent of patients with EV71 disease were < or = 6 months of age (range, 4 weeks to 9 years). All 16 patients had EV71 central nervous system infection. Enterovirus PCR (EV-PCR) of cerebrospinal fluid specimens yielded positive results for only 5 (31.2%) of the 16 patients; all of these patients were < 4 months of age and had less severe disease. However, EV-PCR of upper respiratory tract specimens yielded positive results for 8 (100%) of 8 patients, and EV-PCR of lower gastrointestinal tract specimens yielded positive results for 7 (87.5%) of 8 patients.


CONCLUSIONS
An outbreak of neurologic EV71 disease occurred in Denver, Colorado, during 2003 and 2005. Likely, EV71 disease remains unrecognized in other parts of the United States, because EV-PCR of cerebrospinal fluid frequently yields negative results. EV-PCR of specimens from the respiratory and gastrointestinal tracts had higher diagnostic yields than did EV-PCR of cerebrospinal fluid. EV71 infection should be considered in young children presenting with aseptic meningitis, encephalitis, acute flaccid paralysis, or acute cardiopulmonary collapse. EV71 infection may be an underrecognized emerging disease in the United States.
Pérez-Vélez
Carlos M
CM
Department of Pediatrics, Section of Infectious Diseases, University of Colorado School of Medicine, and The Children's Hospital, Denver, Colorado 80218, USA. anderson.marsha@tchden.org
Anderson
Marsha S
MS
Robinson
Christine C
CC
McFarland
Elizabeth J
EJ
Nix
W Allan
WA
Pallansch
Mark A
MA
Oberste
M Steven
MS
Glodé
Mary P
MP
D020805:Central Nervous System Viral Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology*; D002555:Cerebrospinal Fluid / Q000821:virology; D002648:Child; D002675:Child, Preschool; D003120:Colorado / Q000453:epidemiology; D004196:Disease Outbreaks; D004660:Encephalitis / Q000209:etiology; D029821:Enterovirus A, Human / Q000145:classification* / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D004769:Enterovirus Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000821:virology*; D005260:Female; D041981:Gastrointestinal Tract / Q000821:virology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008582:Meningitis, Aseptic / Q000209:etiology; D009102:Multiple Organ Failure / Q000209:etiology; D010243:Paralysis / Q000209:etiology; D016133:Polymerase Chain Reaction; D012137:Respiratory System / Q000821:virology; D017422:Sequence Analysis, DNA; D014776:Virus Cultivation