Seroprevalence and anti-HEV persistence in the general population of the Republic of San Marino.
The prevalence of anti-HEV was assessed in 2,233 subjects aged 20-79 years in the Republic of San Marino in the years 1990-1991. The sera were tested by ELISA and further confirmed by Western blot (WB) analysis. The overall anti-HEV prevalence was 1.5%. A significant trend by age was observed. Anti-HEV prevalence was 0.6% in subjects <30 years and 3.3% in those older than 70 years of age. Family size larger than four persons (OR = 3.8; 95% CI = 1.8-13.2) was the sole independent predictor of anti-HEV positivity in the multivariate analysis. Anti-HAV and anti-HEV prevalences did not show a parallel trend by age. No association was found either between hepatitis E virus (HEV) or hepatitis C virus (HCV) infections. Follow-up samples 5 years apart were available for 38 out of 54 (70%) anti-HEV ELISA-positive subjects. Eight out of 22 (37%) WB-confirmed anti-HEV-positive subjects were still anti-HEV-positive after 5 years. However, anti-HEV remained positive in all but two (75%) of the subjects with WB-confirmed ELISA positivity value of S/CO > or = 2 (cutoff 1.2), but in only 2 out of the 14 subjects (14%) with a WB-confirmed ELISA positivity value of S/CO < 2 (P < 0.005). None of the 16 subjects ELISA-positive but not WB-confirmed was anti-HEV-positive 5 years apart. Therefore, only a relative proportion of subjects once infected with HEV maintain for at least 5 years anti-HEV antibodies.
Rapicetta
M
M
Laboratory of Virology, Istituto Superiore di Sanità, Rome, Italy.
Kondili
L A
LA
Pretolani
S
S
Stroffolini
T
T
Chionne
P
P
Villano
U
U
Madonna
E
E
Casali
F
F
Gasbarrini
G
G
D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D016751:Hepatitis E / Q000097:blood / Q000453:epidemiology* / Q000276:immunology / Q000821:virology; D016752:Hepatitis E virus / Q000276:immunology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012496:San Marino / Q000453:epidemiology