Postinfectious gastrointestinal disorders following norovirus outbreaks.
BACKGROUND
The US Centers for Disease Control and Prevention estimates 20.9 million norovirus infections annually in the United States. Although the acute disease burden is sizeable, emerging data suggest norovirus may be associated with chronic gastrointestinal problems. We identified known outbreaks in US military recruits and used the Defense Medical Encounter Database (DMED) to identify the risk of new onset functional gastrointestinal disorders (FGD) and gastroesophageal reflux disease (GERD).


METHODS
Subjects reporting for care of acute gastroenteritis (AGE) at a military treatment clinic during 3 known norovirus outbreaks were identified. Each AGE subject was matched with up to 4 subjects with unrelated medical encounters. Medical encounter data were analyzed for the duration of military service time (or a minimum of 1 year) to assess for incident FGD or GERD. Relative risks were calculated using regression models.


RESULTS
We identified 1718 subjects from 3 outbreaks. After controlling for important demographic covariates, the incidence of constipation, dyspepsia, and GERD was approximately 1.5-old higher (P < .01) in AGE-exposed subjects than matched subjects. We also noted variability in outcome incidence across outbreaks.


CONCLUSIONS
It appears that the risk of dyspepsia, constipation, and GERD are higher among those who have AGE during a confirmed norovirus outbreak. Although these findings need confirmation, they suggest that dysmotility may result subsequent to these infections. If confirmed, the costs and morbidity associated with the chronic consequences of norovirus should be considered.
Naval Medical Research Center, Silver Spring, MD, USA. chad.porter@med.navy.mil
Chad K
CK
Porter
Dennis J
DJ
Faix
Danny
D
Shiau
Jennifer
J
Espiritu
Benjamin J
BJ
Espinosa
Mark S
MS
Riddle
D017250:Caliciviridae Infections / Q000150:complications* / Q000453:epidemiology; D002908:Chronic Disease; D015331:Cohort Studies; D003248:Constipation / Q000453:epidemiology* / Q000473:pathology; D004196:Disease Outbreaks; D004415:Dyspepsia / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D005764:Gastroesophageal Reflux / Q000453:epidemiology* / Q000473:pathology; D006801:Humans; D015994:Incidence; D008297:Male; D008889:Military Personnel; D029322:Norovirus / Q000472:pathogenicity*; D012189:Retrospective Studies; D014481:United States; D055815:Young Adult