Epidemic hepatitis E in Pakistan: patterns of serologic response and evidence that antibody to hepatitis E virus protects against disease.
IgM and IgG anti-hepatitis E virus (HEV) patterns were determined in sera collected during a hepatitis outbreak in Pakistan. HEV infection was detected serologically in 122 patients. IgM anti-HEV was detected in specimens collected up to 2 weeks before and 5-7 weeks after hospitalization in 91% and 100%, respectively, of 122 HEV-infected patients. IgG followed a similar pattern. Peak antibody titers appeared 2-4 weeks after hospitalization. At 20 months after hospitalization, IgM anti-HEV was not detected in any of 33 patients; IgG was found in all. IgG anti-HEV appeared to be protective in contracts of patients. This study confirms HEV as the cause of the outbreak, quantifies IgM and IgG anti-HEV responses, provides evidence that IgG anti-HEV protects against hepatitis E, and demonstrates that IgG anti-HEV persists, but at diminished titer, after infection. Hepatitis E in young adults is the result of primary infection with HEV and, if reinfection occurs, it does not commonly cause serious illness.
Bryan
J P
JP
Department of Preventive Medicine and Biometrics, Uniformed Services, University of the Health Sciences, Bethesda, MD 20814-4799.
Tsarev
S A
SA
Iqbal
M
M
Ticehurst
J
J
Emerson
S
S
Ahmed
A
A
Duncan
J
J
Rafiqui
A R
AR
Malik
I A
IA
Purcell
R H
RH
D000914:Antibodies, Viral / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D016751:Hepatitis E / Q000097:blood / Q000453:epidemiology* / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood*; D007297:Inpatients; D010045:Outpatients; D010154:Pakistan / Q000453:epidemiology
D000914:Antibodies, Viral; D007075:Immunoglobulin M; D007073:Immunoglobulin E