Advances and hurdles on the way toward a leprosy vaccine

Abstract

Prevalence rates for leprosy have declined sharply over the past 20 y, with this decline generally attributed to the WHO multi-drug therapy (MDT) campaign to provide free-of-charge treatment to all diagnosed leprosy patients. The success of this program appears to have reached its nadir, however, as evidenced by the stalled decreases in both global prevalence and new case detection rates of leprosy. Mass BCG vaccination for the prevention of tuberculosis (TB) at national levels has had a positive effect on leprosy decline and is often overlooked as an important factor in current leprosy control programs. Because BCG provides incomplete protection against both TB and leprosy, newer more effective TB vaccines are being developed. The impact that application of these vaccines will have on current leprosy control programs is unclear. In this review, we assess the need for vaccines within leprosy control programs. We summarize and discuss leprosy vaccine strategies that have been deployed previously and discuss those strategies that are currently being developed to augment recent breakthroughs in leprosy control.

The potential for vaccination in leprosy elimination: new tools for targeted interventions

“…Several attempts have been made to develop a vaccine specifically for leprosy but, at present, BCG is the only vaccine administered for the prevention of leprosy (reviewed in Duthie et al 2011a). It is noteworthy, however, that leprosy remains prevalent in countries with widespread BCG vaccination programs and, as is the case for TB, protection afforded by BCG vaccination against leprosy appears to wane over time.…”

Emerging and Reemerging Neglected Tropical Diseases: a Review of Key Characteristics, Risk Factors, and the Policy and Innovation Environment

“…Vaccine development for other infectious diseases may have potential, including the bacillus Calmette-Guérin vaccine for tuberculosis, which has been found to offer limited, temporary protection from the bacterium that causes leprosy and the bacteria that cause Buruli ulcer (293). Though these NTDs are not classified as EReNTDs, the successful utilization of existing vaccines used for other infectious diseases may provide another method for encouraging EReNTD research and innovation.…”

The armadillo: a model for neuropathy of leprosy and potentially other neurodegenerative diseases

“…In addition, an effective vaccine is urgently needed to prevent leprosy transmission (Duthie et al, 2011). Since the 1960s, potential leprosy vaccine candidates have been tested in conventional laboratory mice (Shepard, 1966).…”