Integration of hepatitis B vaccination into rural African primary health care programmes.
OBJECTIVE
To determine the efficacy of hepatitis B vaccine when added to the routine expanded programme on immunisation under field conditions in rural Africa.


METHODS
Infants were immunised according to two schedules--an early schedule at birth, 3 months, and 6 months and a later schedule to correspond with routine vaccination in the expanded programme on immunisation at 3 months, 4 1/2 months, and 6 months.


METHODS
Venda, northern Transvaal, South Africa, a self governing region of 7460 square kilometers varying from rural villages to small towns.


METHODS
The 1989 birth cohort of Venda.


METHODS
Coverage for hepatitis B vaccine at first, second, and third doses; serological assessment of vaccine efficacy by prevalence of antibodies to hepatitis B surface antigen in infants who had completed the three dose course of immunisation; antibodies to hepatitis B core antigen to determine if natural infection occurred.


RESULTS
Vaccine coverage for hepatitis B dropped sharply from 99% to 53% to 39% for the first, second, and third dose respectively. In contrast, vaccine coverage was maintained at 97-99% for the three doses of poliomyelitis vaccine. Serological evaluation of vaccine efficacy showed that only 3.5% of recipients of all three doses failed to develop antibodies to hepatitis B surface antigen. Only 6.6% of vaccine recipients were vaccinated according to either the early or later schedules whereas 93.4% received their doses of vaccine at intervals beyond the limits of either of the planned schedules. There was, however, no significant difference in seroconversion to the surface antigen between the "unscheduled" or scheduled groups of those who were vaccinated according to the early or late schedules. The pattern of prevalence of antibodies to hepatitis B core antigen, which showed a sharp fall in children aged over 7 months, suggested that the antibodies were acquired passively rather than by active infection.


CONCLUSIONS
Supplementation of the present expanded programme on immunisation with hepatitis B vaccine in rural Africa is fraught with difficulties. However, the vaccine was effective within a fairly wide spacing of dosage. Adding hepatitis B vaccine to diphtheria, tetanus, and pertussis as a tetravalent vaccine is proposed as a means of effectively integrating it into the expanded programme on immunisation in Third World settings.
Schoub
B D
BD
National Institute for Virology, Sandringham, South Africa.
Johnson
S
S
McAnerney
J M
JM
Blackburn
N
N
Kew
M C
MC
McCutcheon
J P
JP
Carlier
N D
ND
D003906:Developing Countries; D006509:Hepatitis B / Q000517:prevention & control*; D006510:Hepatitis B Antibodies / Q000032:analysis; D006512:Hepatitis B Core Antigens / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000276:immunology; D017325:Hepatitis B Vaccines; D006515:Hepatitis B virus / Q000276:immunology; D006801:Humans; D007115:Immunization Schedule; D007223:Infant; D007231:Infant, Newborn; D011320:Primary Health Care / Q000458:organization & administration*; D012423:Rural Health; D013019:South Africa; D013997:Time Factors; D014611:Vaccination; D014614:Vaccines, Synthetic; D014761:Viral Hepatitis Vaccines
D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D014614:Vaccines, Synthetic; D014761:Viral Hepatitis Vaccines