[The immunological effects of three doses of a live attenuated hepatitis A vaccine (H2 strain) in 8 years].
OBJECTIVE
To observe the immunological effects of three doses of H2 strain live attenuated hepatitis A vaccine 8 years after the administration and to compare with that of one dose of the vaccine.


METHODS
In a country area, 110 children of 1 to 7 years old susceptible to HAV were screened and administered with one dose of the vaccine, as group B; Group A were 42 children from one of the villages and administered with 3 doses of the vaccine according to 0, 2, 6 month schedule. Blood samples were taken for the children 1, 2, 6, 7, 8, 12, 24, 36 and 96 months after the administrations respectively and detected for anti-HAV antibody.


RESULTS
For group B, the sero conversion rate of anti-HAV and GMC reached peak at 92.2% and 126.2 mIU/ml respectively, and then, began to drop with time; For group A, after 2 dose of the vaccine, the sero-conversion rate reached 100%, and the GMC reached peak of 2 739 mIU/ml one month after the third dose at 7 months. So that, group A has a better short-term immunological effects than that of group B. During 36 through 96 months, the anti-HAV positive rate in group B was 75%-71% and 80-89 mIU/ml respectively, and comparatively in group A were 100% and 918.2-480.6 mIU/ml respectively. The differences between group A and B were significantly important.


CONCLUSIONS
A 3-dose schedule administration of H2 strain live attenuated hepatitis A vaccine has better immunological effects than 1-dose schedule in 8years and further observations are needed.
Liu
Huai-Feng
HF
Zhengding County Hospital of Chinese Medicine, Zhengding, Hebei 050800, Chin.a
Zhang
Xin-Jiang
XJ
Zhang
Jian-Li
JL
Hao
Zhi-Yong
ZY
Zhang
Zhi-Yong
ZY
Ma
Jing-Chen
JC
Chen
Ji-Chao
JC
Chu
Juan
J
Wang
Xuan-Yi
XY
Xu
Zhi-Yi
ZY
D002648:Child; D002675:Child, Preschool; D005260:Female; D006506:Hepatitis A / Q000097:blood / Q000276:immunology* / Q000517:prevention & control; D035922:Hepatitis A Antibodies / Q000097:blood / Q000276:immunology; D022362:Hepatitis A Vaccines / Q000008:administration & dosage* / Q000276:immunology; D006801:Humans; D007115:Immunization Schedule; D007117:Immunization, Secondary; D007223:Infant; D008297:Male; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000276:immunology
D035922:Hepatitis A Antibodies; D022362:Hepatitis A Vaccines; D014613:Vaccines, Attenuated