High incidence of tuberculosis among HIV-infected infants: evidence from a South African population-based study highlights the need for improved tuberculosis control strategies.
BACKGROUND
There are limited population-based estimates of tuberculosis incidence among human immunodeficiency virus (HIV)-infected and HIV-uninfected infants aged < or =12 months. We aimed to estimate the population-based incidence of culture-confirmed tuberculosis among HIV-infected and HIV-uninfected infants in the Western Cape Province, South Africa.


METHODS
The incidences of pulmonary, extrapulmonary, and disseminated tuberculosis were estimated over a 3-year period (2004-2006) with use of prospective representative hospital surveillance data of the annual number of culture-confirmed tuberculosis cases among infants. The total number of HIV-infected and HIV-uninfected infants was calculated using population-based estimates of the total number of live infants and the annual maternal HIV prevalence and vertical HIV transmission rates.


RESULTS
There were 245 infants with culture-confirmed tuberculosis. The overall incidences of tuberculosis were 1596 cases per 100,000 population among HIV-infected infants (95% confidence interval [CI], 1151-2132 cases per 100,000 population) and 65.9 cases per 100,000 population among HIV-uninfected infants (95% CI, 56-75 cases per 100,000 population). The relative risk of culture-confirmed tuberculosis among HIV-infected infants was 24.2 (95% CI, 17-34). The incidences of disseminated tuberculosis were 240.9 cases per 100,000 population (95% CI, 89-433 cases per 100,000 population) among HIV-infected infants and 14.1 cases per 100,000 population (95% CI, 10-18 cases per 100,000 population) among HIV-uninfected infants (relative risk, 17.1; 95% CI, 6-34).


CONCLUSIONS
This study indicates the magnitude of the tuberculosis disease burden among HIV-infected infants and provides population-based comparative incidence rates of tuberculosis among HIV-infected infants. This high risk of tuberculosis among HIV-infected infants is of great concern and may be attributable to an increased risk of tuberculosis exposure, increased immune-mediated tuberculosis susceptibility, and/or possible limited protective effect of bacille Calmette-Guérin vaccination. Improved tuberculosis control strategies, including maternal tuberculosis screening, contact tracing of tuberculosis-exposed infants coupled with preventive chemotherapy, and effective vaccine strategies, are needed for infants in settings where HIV infection and tuberculosis are highly endemic.
Hesseling
A C
AC
Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Health Sciences, Stellenbosch University, PO Box 19063, Tygerberg, South Africa. annekeh@sun.ac.za
Cotton
M F
MF
Jennings
T
T
Whitelaw
A
A
Johnson
L F
LF
Eley
B
B
Roux
P
P
Godfrey-Faussett
P
P
Schaaf
H S
HS
D015658:HIV Infections / Q000150:complications*; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification; D013019:South Africa / Q000453:epidemiology; D014376:Tuberculosis / Q000453:epidemiology*