Genome-wide association study of leprosy in Malawi and Mali.

Leprosy is a chronic infection of the skin and peripheral nerves caused by Mycobacterium leprae. Despite recent improvements in disease control, leprosy remains an important cause of infectious disability globally. Large-scale genetic association studies in Chinese, Vietnamese and Indian populations have identified over 30 susceptibility loci for leprosy.

BCG re-vaccination in Malawi: 30-year follow-up of a large, randomised, double-blind, placebo-controlled trial.

Background: A large, double-blind, randomised, placebo-controlled trial of repeat BCG found 49% efficacy against leprosy but no protection against tuberculosis after 6-9 years' follow-up in 1995. We report here additional follow-up, which resulted in greatly increased tuberculosis case numbers, and allowed subgroup analysis.

Methods: Nearly 47 000 individuals of all ages living in northern Malawi with a BCG vaccine scar were randomly assigned (1:1) between 1986 and 1989 to receive a second BCG or placebo.

Use of short tandem repeat sequences to study Mycobacterium leprae in leprosy patients in Malawi and India.

Background: Inadequate understanding of the transmission of Mycobacterium leprae makes it difficult to predict the impact of leprosy control interventions. Genotypic tests that allow tracking of individual bacterial strains would strengthen epidemiological studies and contribute to our understanding of the disease.

Methodology/principal Findings: Genotyping assays based on variation in the copy number of short tandem repeat sequences were applied to biopsies collected in population-based epidemiological studies of leprosy in northern Malawi, and from members of multi-case households in Hyderabad, India.

Trends in tuberculosis and the influence of HIV infection in northern Malawi, 1988-2001.

Objective: To document the changing incidence and patterns of tuberculosis (TB) in rural Africa and the extent to which they are influenced by HIV.

Methods: As part of longstanding epidemiological studies in Karonga District, Malawi, a series of case control studies of TB and HIV were conducted from 1988 onwards. Data from these studies, from a total population survey, and from the Malawi national census have been used to reconstruct the changes in the TB epidemic in the area from 1988 to 2001, examining the role of HIV.

Trends and measurement of HIV prevalence in northern Malawi.

Background: Most data on HIV prevalence in Malawi come from antenatal clinic (ANC) surveillance and are, therefore, subject to bias.

Objectives: HIV prevalence and risk factors were measured using population-based data to assess the accuracy of ANC surveillance and changes in prevalence and risk factors for HIV over time.

Methods: HIV prevalence was measured in 1988-1993 and 1998-2001 in community controls from case-control studies of mycobacterial disease in Karonga District, Malawi.

Early evolution of the human immunodeficiency virus type 1 subtype C epidemic in rural Malawi.

We have tracked the early years of the evolution of the human immunodeficiency virus type 1 (HIV-1) epidemic in a rural district of central east Africa from the first documented introductions of subtypes A, D, and C to the present predominance of subtype C. The earliest subtype C sequences ever reported are described. Blood samples were collected on filter papers from 1981 to 1984 and from 1987 to 1989 from more than 44,000 individuals living in two areas of Karonga District, Malawi.

Kinetics of delayed-type hypersensitivity to tuberculin induced by bacille Calmette-Guérin vaccination in northern Malawi.

During 1986-1989, a bacille Calmette-Guérin (BCG) vaccine trial was carried out in northern Malawi. The effects of age, sex, and prevaccination delayed-type hypersensitivity (DTH) on the time course of the DTH response over 1-36 months after vaccination were studied in 2418 persons. DTH response increased rapidly, to peak at 31-90 days after vaccination, when most persons had a measurable response.