Advances and hurdles on the way toward a leprosy vaccine

Figures & data

Figure 1. New case detection rates in countries reporting over 1000 annual leprosy cases since 2002.

Table 1. Summary of clinical trials to identify novel vaccines for leprosy

	vaccine	location	overall study size	study follow-up (years)	% protection	reference
	BCG BCG + killed M. leprae	Venezuela	29, 113	5	56 54	^58
	BCG BCG + killed M. leprae	Malawi	121, 020	6–9	49 49	^59
Whole bacteria	BCG BCG + killed M. leprae M. w ICRC	India	171, 400	4–7	34 64 26 66	^61
	M. w (killed)	India	29, 420	8–10	39	^64
	BCG M. vaccae BCG + M. vaccae	Vietnam	432	8	58 55 66	^65
	BCG	composite of multiple studies (meta-analysis)			26–41^a (experimental) 61 (observational)	^50 ^, ^51
Sub-unit	None reported

^a Setia and colleagues selected all the studies (experimental and observational) that described the efficacy of BCG with prevention of clinical leprosy (defined according to clinical and/or microscopic criteria) and excluded studies that measured the protective effect of BCG combined with other therapies (eg, chemotherapy, killed M leprae)/ Their meta-analysis was restricted to studies that measured the protective effect of BCG alone. Merle and colleagues selected only controlled trials with a clearly defined placebo (or nonintervention) group. To be included in their analysis, case-control studies had to define the criteria for selecting cases and controls, as well as the method for determining their BCG vaccination status.

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