Single nucleotide polymorphism-based molecular typing of M. leprae from multicase families of leprosy patients and their surroundings to understand the transmission of leprosy.

The exact mode of transmission of leprosy is not clearly understood; however, many studies have demonstrated active transmission of leprosy around a source case. Families of five active leprosy cases and their household contacts were chosen from a high endemic area in Purulia. Fifty-two soil samples were also collected from different areas of their houses. DNA was extracted from slit-skin smears (SSS) and soil samples and the Mycobacterium leprae-specific RLEP (129 bp) region was amplified using PCR. Molecular typing of M. leprae was performed for all RLEP PCR-positive samples by single nucleotide polymorphism (SNP) typing and confirmation by DNA sequencing. SSS of these five patients and six out of the total 28 contacts were PCR positive for RLEP whereas 17 soil samples out of 52 showed the presence of M. leprae DNA. SNP typing of M. leprae from all RLEP PCR-positive subjects (patients and smear-positive contacts) and 10 soil samples showed the SNP type 1 genotype. M. leprae DNA from the five leprosy patients and the six contacts was further subtyped and the D subtype was noted in all patients and contacts, except for one contact where the C subtype was identified. Typing followed by subtyping of M. leprae clearly revealed that either the contacts were infected by the patients or both patients and contacts had the same source of infection. It also revealed that the type of M. leprae in the soil in the inhabited areas where patients resided was also of the same type as that found in patients.

Disability adjusted working life years (DAWLYs) of leprosy affected persons in India.

BACKGROUND & OBJECTIVES: Disability-adjusted life years (DALYs) have been accepted as a useful method to estimate the burden of disease, and can be adapted to determine the number of productive years lost due to the disability. DALY has been reported for many studies but not for leprosy. Hence this study was carried out in three States of India. In view of the fact that in this study, productive working years are used, the term is modified as DAWLY. METHODS: A representative random sample of 150 leprosy affected persons, 50 from each States of Uttar Pradesh, West Bengal and Chhattisgarh, was chosen, and data were collected on detailed work-life history, occupation, time when leprosy was discovered, reported and treatment started, break of job/loss of income due to leprosy. The loss of wages and durations were used to compute the life-years lost due to leprosy, and summarized over the average total duration of 42 years of productive work-life from 18 to 60 years. The percentage losses were determined and differences tested for statistical significance. RESULTS: The overall mean (± SE) disability adjusted working life years was 28.6 (±0.67), a reduction of 13.4 yr from the ideal productive working life period of 42 yr. The youngest patients with disability had a reduction of 41.4 per cent, as compared to the oldest patients. There was a significant increase in loss based on year for those whose disability started earlier (P=0.0024). INTERPRETATION & CONCLUSIONS: On an average, 30 per cent of the leprosy affected person's work life is lost due to disability.