Hepatitis E antibody seroconversion without disease in highly endemic rural Egyptian communities.
Hepatitis E virus (HEV) is enterically transmitted and causes self-limiting acute viral hepatitis (AVH) primarily in less developed countries. A prospective cohort study to assess incidence of, and risk factors for, seroconversion to HEV (anti-HEV) was conducted in two Egyptian villages with a 67.7% anti-HEV prevalence. Nine hundred and nineteen villagers who were initially anti-HEV-negative were followed for 10.7 months. Thirty-four (3.7%) had strong anti-HEV serologic responses at follow-up giving an estimated anti-HEV incidence of 41.6/1,000 person-years. No significant associations were found between anti-HEV seroincidence and demographic and socioeconomic factors, source of water, household plumbing or sanitation, hand and vegetable washing, ownership of animals, jaundice and many other variables. None of the seroconverting subjects gave a history compatible with AVH during the interval. We hypothesize that both zoonotic and anthroponotic transmission of avirulent (possibly genotype-3) HEV is occurring extensively in these rural villages. An alternative explanation for the lack of morbidity among anti-HEV incident cases could be initial asymptomatic infections occur during early childhood with subsequent antibody titer boosting without illness upon re-exposure to the virus.
Stoszek
Sonia K
SK
International Health Division, Department of Epidemiology and Preventive Medicine, School of Medicine, University of Maryland, 660 W. Redwood Street, Baltimore, MD 20201, USA.
Engle
Ronald E
RE
Abdel-Hamid
Mohamed
M
Mikhail
Nabiel
N
Abdel-Aziz
Fatma
F
Medhat
Ahmed
A
Fix
Alan D
AD
Emerson
Suzanne U
SU
Purcell
Robert H
RH
Strickland
G Thomas
GT
D000293:Adolescent; D000328:Adult; D002648:Child; D015331:Cohort Studies; D004534:Egypt / Q000453:epidemiology; D019353:Endemic Diseases; D005260:Female; D006508:Hepatitis Antibodies / Q000097:blood*; D016752:Hepatitis E virus / Q000276:immunology*; D006525:Hepatitis, Viral, Human / Q000453:epidemiology* / Q000635:transmission; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012423:Rural Health; D016036:Seroepidemiologic Studies
D006508:Hepatitis Antibodies