Roy et al show that BCG vaccination protects against both M tuberculosis infection and progression of infection to disease. However, it is important to recognise that vaccination with BCG confers additional benefits to those discussed by Roy: namely, protection against M leprae and, perhaps, other non-tuberculous mycobacterial species. Whilst the incidence and prevalence of leprosy has declined markedly over the last 10 years it remains a significant public health challenge, with over 200,000 new cases per year [1]. A meta-analysis shows that BCG vaccination seems to give an average protective effect against leprosy of 26%, albeit with significant heterogeneity between studies [2]. Similarly, BCG vaccination of leprosy contacts is also protective, both with [3] and without [4] additional chemo-prophylaxis with rifampicin. BCG vaccination may also provide some protection against a third mycobacterial infection: Buruli ulcer, caused by M ulcerans [5]. Although the protective effects of BCG vaccination against non-tuberculous mycobacteria are limited, and may not provide a primary reason for widespread use, these additional benefits do constitute a secondary argument for BCG vaccination in addition to the main aim of preventing M tuberculosis infection and disease.
References
[1] World Health Organization. Global leprosy situation, 2012. Weekly Epidemiological Record, 2012; 87:317-328
[2] Maninder Singh Setia, Craig Steinmaus, Christine S Ho, et al. The role of BCG in prevention of leprosy: a meta-analysis. Lancet Infectious Diseases, 2006; 6:162-170
[3] Ron P Schuring, Jan Hendrik Richardus, David Pahan, et al. Protective effect of the combination BCG vaccination and rifampicin prophylaxis in leprosy prevention. Vaccine, 2009, 27:7125-7128
[4] NC Duppre, LAB Camacho, SS da Cunha, et al. Effectiveness of BCG vaccination among leprosy contacts: a cohort study. Transactions of the Royal Society of Tropical Medicine and Hygiene, 2008; 102:631-638
[5] van der Werf T S, Stienstra Y, Johnson R C et al. Mycobacterium ulcerans disease. Bulletin of the World Health Organization, 2005, 83: 785-791
Competing interests:
No competing interests
11 August 2014
Peter M Fernandes
Clinical Lecturer in Neurology
University of Edinburgh
Department of Clinical Neurosciences, Western General Hospital, Edinburgh
Rapid Response:
Roy et al show that BCG vaccination protects against both M tuberculosis infection and progression of infection to disease. However, it is important to recognise that vaccination with BCG confers additional benefits to those discussed by Roy: namely, protection against M leprae and, perhaps, other non-tuberculous mycobacterial species. Whilst the incidence and prevalence of leprosy has declined markedly over the last 10 years it remains a significant public health challenge, with over 200,000 new cases per year [1]. A meta-analysis shows that BCG vaccination seems to give an average protective effect against leprosy of 26%, albeit with significant heterogeneity between studies [2]. Similarly, BCG vaccination of leprosy contacts is also protective, both with [3] and without [4] additional chemo-prophylaxis with rifampicin. BCG vaccination may also provide some protection against a third mycobacterial infection: Buruli ulcer, caused by M ulcerans [5]. Although the protective effects of BCG vaccination against non-tuberculous mycobacteria are limited, and may not provide a primary reason for widespread use, these additional benefits do constitute a secondary argument for BCG vaccination in addition to the main aim of preventing M tuberculosis infection and disease.
References
[1] World Health Organization. Global leprosy situation, 2012. Weekly Epidemiological Record, 2012; 87:317-328
[2] Maninder Singh Setia, Craig Steinmaus, Christine S Ho, et al. The role of BCG in prevention of leprosy: a meta-analysis. Lancet Infectious Diseases, 2006; 6:162-170
[3] Ron P Schuring, Jan Hendrik Richardus, David Pahan, et al. Protective effect of the combination BCG vaccination and rifampicin prophylaxis in leprosy prevention. Vaccine, 2009, 27:7125-7128
[4] NC Duppre, LAB Camacho, SS da Cunha, et al. Effectiveness of BCG vaccination among leprosy contacts: a cohort study. Transactions of the Royal Society of Tropical Medicine and Hygiene, 2008; 102:631-638
[5] van der Werf T S, Stienstra Y, Johnson R C et al. Mycobacterium ulcerans disease. Bulletin of the World Health Organization, 2005, 83: 785-791
Competing interests: No competing interests