The risk of disseminated Bacille Calmette-Guerin (BCG) disease in HIV-infected children

Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Health Sciences, Stellenbosch University, P.O. Box 19063, Tygerberg, 7505, South Africa.
Vaccine (Impact Factor: 3.62). 02/2007; 25(1):14-8. DOI: 10.1016/j.vaccine.2006.07.020
Source: PubMed


Bacille Calmette-Guerin (BCG), a live attenuated Mycobacterium bovis vaccine, poses a risk to human immunodeficiency virus (HIV)-infected children; this risk has not been well quantified. We estimate the risk of disseminated BCG disease in HIV-infected children in a setting highly endemic for tuberculosis and HIV.
We conducted a prospective hospital-based surveillance study in the Western Cape Province, South Africa. Clinical and laboratory-confirmed cases of disseminated BCG disease in children<1 year of age from January 2002 to December 2004 at a referral hospital were used as numerator data. Denominator data for calculations of disseminated BCG risk were obtained through estimating the total number of HIV-infected infants receiving BCG based on the known vaccination coverage in the study setting, combined with population data on the total number of children<1 year of age, the known HIV prevalence amongst women attending public antenatal care facilities and different scenarios (5-15%) for the rate of vertical HIV transmission.
Nine cases of disseminated BCG disease were identified over the study period, seven of these were in HIV-infected infants. The estimated risk for HIV-infected infants to develop disseminated BCG disease, given a 95% BCG coverage and an HIV prevalence of 12.4-15.4% amongst women, were as follows for different scenarios of vertical HIV transmission: 329-417/100,000 vaccinees (assuming 5% vertical HIV transmission), 164-208/100,000 vaccinees (assuming 10% vertical HIV transmission) and 110-139/100,000 vaccinees (assuming 15% vertical HIV transmission).
The risk of disseminated BCG disease is increased several hundred fold in HIV-infected infants compared to the documented risk in HIV-uninfected infants. Data on the protective effect of BCG in HIV-exposed and infected children is lacking. Population- and hospital-based surveillance is vitally important to more accurately estimate the safety and benefits of BCG in HIV-exposed and infected infants.

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Available from: Ben Marais, Aug 27, 2014
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    • "There has been particular concern for the role of HIV infection in the safety of BCG vaccination [4]. A recent retrospective study documented a high frequency of BCG infection with complications in HIV-infected infants [5]. Current WHO vaccination policy does not recommend BCG vaccination of newborn infants with a known HIV-infection status, with or without infection symptoms [2]. "
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    • "However, it can cause severe disseminated disease, named BCG-osis, in patients affected by some primary immunodeficiency, such as severe combined immunodeficiency and chronic granulomatous disease [16]. Different studies revealed an increased risk of disseminated BCG disease in HIV-infected children, even if asymptomatic at time of vaccination [17,18]. Thus, WHO Global Advisory Committee on Vaccine Safety recommends that BGC should not be administered in HIV-infected patients [19]. "
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    • "HIVinfected infants face a higher risk of TB infection [2], and pregnant women co-infected with HIV and TB are more likely to transmit both HIV and TB to their infants [2] [3]. The Bacille Calmette–Guérin (BCG) vaccine for prevention of TB infection can disseminate in HIV-infected infants with a case fatality of 75% [4]. The high morbidity and mortality associated with HIV and TB disease in infants underscore the urgent need for a safe neonatal vaccine to prevent pediatric HIV and TB infections. "
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