A case-control study of protection against tuberculosis by BCG revaccination in Recife, Brazil.
METHODS
Metropolitan region of Recife, Brazil.


OBJECTIVE
To estimate the additional protection against tuberculosis (TB) provided by a second dose of bacille Calmette-Guérin (BCG) vaccine.


METHODS
Case-control study. Cases were cases of TB newly diagnosed by the TB control programme, independent of clinical form. Three matched neighbourhood controls were selected using a systematic routine, starting from the case's address. The matching was within the age groups 7-9, 10-14 and 15-19 years.


RESULTS
Analysis was conducted among 169 cases and 477 controls. For the efficacy of BCG revaccination against TB overall, matched (crude) vaccine effectiveness (VE) was -3 (95% CI -50-29) and matched (adjusted) VE was 8 (95% CI -77-52).


CONCLUSIONS
This study suggests that a second dose of BCG does not offer additional protection. Revaccination should not be offered. As large numbers of subjects are already vaccinated and vaccine appears to offer some protection in older subjects, further studies with larger sample sizes could investigate the potential efficacy of revaccination with BCG in the age group > or = 15 years.
Dantas
O M S
OM
Department of Mother and Child Health, Federal University of Pernambuco, Recife, Brazil. odimariles@globo.com
Ximenes
R A de A
RA
de Albuquerque
M de F P M
Mde F
da Silva
N L C L
NL
Montarroyos
U R
UR
de Souza
W V
WV
Pereira
T C C
TC
Campelo
A R L
AR
Rodrigues
L C
LC
D000293:Adolescent; D000328:Adult; D001500:BCG Vaccine / Q000008:administration & dosage*; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D012959:Socioeconomic Factors; D014376:Tuberculosis / Q000453:epidemiology / Q000517:prevention & control*; D014505:Urban Population
D001500:BCG Vaccine