Combined passive and active immunoprophylaxis for preventing perinatal transmission of the hepatitis B virus carrier state in Shizuoka, Japan during 1980-1994.
BACKGROUND
Efficacy and limits in preventing perinatal infection with hepatitis B virus (HBV) have been examined in a model area in Japan.


METHODS
In Shizuoka (population of 3.6 million), immunoprophylaxis of perinatal HBV infection was started in 1980 in four institutions (Hamamatsu Medical College, Shimada City Hospital, Shizuoka Kodomo Hospital and Numazu City Hospital). Babies born to carrier mothers with hepatitis B e antigen (HBeAg) in serum received hepatitis B immune globulins at birth and 2 months thereafter and vaccines at 2, 3 and 5 months after birth.


RESULTS
Overall, 980 of the 1030 babies born to HBeAg-positive carrier mothers were protected by the immunoprophylaxis during the 15 years from 1980 to 1994 with an efficacy of 95.1%. From 1986 to 1994 while the national immunoprophylaxis was conducted, 329,674 of the 346,637 (95.1%) expectant mothers were tested, and 2081 (0.63%) of them were positive for hepatitis B surface antigen (HBsAg). The immunoprophylaxis was given only to babies born to 764 (36.7%) of the 2081 mothers who tested positive for HBeAg. Of the 494 babies receiving immunoprophylaxis, in whom HBsAg was followed monthly after birth, 462 (93.5%) were protected. The HBV carrier state developed in the remaining 32 (6.5%) babies, 10 of whom (31.3% of the 32) turned positive for HBsAg within 1 month after birth, most likely owing to infection in utero.


CONCLUSIONS
Passive-active immunoprophylasxis of high-risk babies was highly efficacious in preventing perinatal transmission of the HBV carrier state. Most failures (approximately 70%) occurred in the high-risk babies who were exposed to HBV after birth, and would have been avoided by careful and extensive execution of the immunoprophylaxis.
Noto
Hiroshi
H
Department of Obstetrics, Hamamatsu Medical College, Shizuoka, Japan.
Terao
Toshihiko
T
Ryou
Shigeo
S
Hirose
Yasuyuki
Y
Yoshida
Takami
T
Ookubo
Hideo
H
Mito
Hidetoshi
H
Yoshizawa
Hiroshi
H
D000293:Adolescent; D002353:Carrier State; D002648:Child; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission*; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006801:Humans; D007116:Immunization, Passive; D007136:Immunoglobulins / Q000627:therapeutic use*; D016233:Immunotherapy, Active / Q000379:methods*; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D007564:Japan / Q000453:epidemiology; D009313:National Health Programs; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000821:virology; D015995:Prevalence; D016896:Treatment Outcome
D006514:Hepatitis B Surface Antigens; D007136:Immunoglobulins