Norwalk virus gastroenteritis among Israeli soldiers: lack of evidence for flyborne transmission.
BACKGROUND
Paired sera collected from subjects before and after a fly-control intervention trial conducted in the Israel Defense Force (IDF) were tested for seroconversion to Norwalk virus (NV) to examine the role of NV as a cause of diarrhea in this population and to ascertain whether flies might also be implicated in transmission.


METHODS
An enzyme-linked immunosorbent assay (ELISA), using recombinant NV capsid proteins (rNV) as antigen was employed to determine the seroconversion rate in a sample of 444 subjects.


RESULTS
During 11-week field training cycles, 18% of IDF soldiers who were tested had an NV infection defined as a > or = 4-fold rise in antibody, yielding a cumulative incidence of nearly one infection (0.95) per soldier per year. The rate of seroconversion was nearly twice as high among soldiers who recalled having diarrhea as among those who did not, but the rates did not differ significantly between soldiers in the fly intervention areas and those in the control areas.


CONCLUSIONS
NV is a common cause of enteric infections and diarrhea among Israeli soldiers who serve under field conditions, but unlike infections with Shigella and enterotoxigenic Escherichia coli, transmission of NV cannot be interrupted with an aggressive program of fly-control.
Cohen
D
D
Medical Corps, Israel Defense Force, Military Post 02149. danic@netvision.net.il
Monroe
S S
SS
Haim
M
M
Slepon
R
R
Ashkenazi
I
I
Estes
M K
MK
Glass
R I
RI
D000293:Adolescent; D000328:Adult; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D017250:Caliciviridae Infections / Q000453:epidemiology / Q000635:transmission* / Q000821:virology; D002213:Capsid / Q000235:genetics / Q000276:immunology; D036022:Capsid Proteins; D004175:Diptera / Q000821:virology*; D005759:Gastroenteritis / Q000821:virology*; D006801:Humans; D007300:Insect Control; D007557:Israel / Q000453:epidemiology; D008297:Male; D008889:Military Personnel; D009663:Norwalk virus / Q000276:immunology; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology
D000914:Antibodies, Viral; D036022:Capsid Proteins; C121877:Norwalk virus capsid; D011994:Recombinant Proteins