Acquirement and disappearance of HBsAg and anti-HCV in an aged population: a follow-up study in an endemic township.
BACKGROUND
HBsAg and anti-hepatitis C virus (anti-HCV) are stable markers and widely used. The seroconversion and seroclearance of HBsAg and anti-HCV are important for disease control and prognosis of diseases.


OBJECTIVE
To investigate acquirement and disappearance of HBsAg and anti-HCV in an endemic area.


METHODS
Seven years after a community screening, 1002 of 2909 residents of Tzukuan Township were recruited. HBsAg, anti-HCV and alanine transaminase (ALT) were checked in all who participated and hepatitis B virus (HBV) DNA, anti-HBs, anti-HBc, HCV RNA, anti-HDV and upper abdominal ultrasonography were studied in different groups.


RESULTS
There were 461 male and 541 female residents with a mean age of 66.7 ± 8.6 years. No new HBsAg carrier was noted and the HBsAg clearance rate was 1.58% per year. One of the 17 cases with HBsAg clearance had positive HBV DNA, three had ALT elevation, two had cirrhosis and seven had anti-HBs seroconversion. Quantitative of HBsAg and HBV DNA were concordant and 78.1% subjects had low levels of titration. Anti-HBc alone contributed to 32.1% and was prominent in old age and the anti-HCV-positive group. The anti-HCV seroconversion rate was only 0.74% per year and household transmission was the only risk factor. Only 37.5% of cases with anti-HCV seroconversion had HCV viraemia and the anti-HCV seroreversion rate was 0.63% per year. The anti-HDV seroconversion rate was 0.72% per year and no subject showed anti-HDV clearance.


CONCLUSIONS
Much higher rates of HBsAg seroclearance, anti-HCV seroreversion and anti-HBc alone were noted in this endemic area and no subject showed anti-HDV clearance.
Health Center of Zihguan Township, Kaohsiung, Taiwan.
Pei-Shan
PS
Tsai
Chang-Jung
CJ
Chang
Kow-Tong
KT
Chen
Kuo-Chin
KC
Chang
Shu-Fen
SF
Hung
Jing-Houng
JH
Wang
Chao-Hung
CH
Hung
Chien-Hung
CH
Chen
Po-Lin
PL
Tseng
Kwong-Ming
KM
Kee
Yi-Hao
YH
Yen
Chin-Chen
CC
Tsai
Sheng-Nan
SN
Lu
D000005:Abdomen / Q000000981:diagnostic imaging; D000368:Aged; D000410:Alanine Transaminase / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006509:Hepatitis B / Q000097:blood* / Q000453:epidemiology*; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006526:Hepatitis C / Q000097:blood* / Q000453:epidemiology*; D018937:Hepatitis C Antibodies / Q000097:blood*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016036:Seroepidemiologic Studies; D011795:Surveys and Questionnaires; D013624:Taiwan / Q000453:epidemiology; D014463:Ultrasonography
D006514:Hepatitis B Surface Antigens; D018937:Hepatitis C Antibodies; D000410:Alanine Transaminase