ANTI-HAV AND ANTI-HCV
PREVALENCE IN SINGAPORE
Chan SH, Tan KL, Dong F, Khoo C*, Poerschke G*
Faculty of Medicine, University of Singapore; MSD Singapore*,MSD
Asia*
Introduction: We studied hepatitis A [HAV] and C [HCV]
prevalence in a cross-sectional sample of Singaporean children. Hepatitis A
infection in people with existing Hepatitis B or C disease causes higher
morbidity and mortality burden. Local surveillance is important to
determine epidemiology changes, effective vaccination strategies and assessing
cost-effectiveness.
Methods: From April 1996 - December 1997, 1173 blood samples
were obtained from 12 age cohorts, birth - 20 years. After centrifugation,
serum was stored for testing at ¨C70 C. at the WHO Immunology Centre,
Singapore.
Results:
Age groups
|
N
|
anti-HAV:% (n)
|
anti-HCV: %(n)
|
|
Cord
blood
|
80
|
45.5
(36)
|
0
|
|
£ 1 month
|
100
|
42
(42)
|
0.1
(1)
|
|
2
- 6 months
|
26
|
11.5
(3)
|
0
|
|
7
- 9 months
|
26
|
7.7
(2)
|
0
|
|
10
- 12 months
|
28
|
0
|
0
|
|
1
- 2 years
|
209
|
0.5
(1)
|
0
|
|
3
- 4 years
|
144
|
0.7
(1)
|
0
|
|
5
- 10 years
|
359
|
0
|
0.28
(1)
|
|
11
- 12 years
|
158
|
0.6
(1)
|
0
|
|
13
¨C 20 years
|
34
|
0
|
2.5
(1)
|
|
>
20 years
|
9
|
33.3
(3)
|
0
|
|
Total/prevalence
|
1173
|
7.6 (89)
|
0.26 (3)
|
Discussion: In our study population HAV prevalence was 7.6% and
HCV 0.26% suggesting superinfection with HAV will be rare. Anti-HAV was highest in the cord blood group
reflecting maternal antibodies. They then decreased, but could still be
detected at 9 months. Universal immunization of infants with HA vaccine
would offer protection of susceptible adolescents and adults by herd
immunity, but more clinical work needs to be done to identify best age and
vaccination strategy within an EPI.