Quantitative bacterial examination of domestic water supplies in the Lesotho Highlands: water quality, sanitation, and village health.

Reported are the results of an examination of domestic water supplies for microbial contamination in the Lesotho Highlands, the site of a 20-year-old hydroelectric project, as part of a regional epidemiological survey of baseline health, nutritional and environmental parameters. The population's hygiene and health behaviour were also studied. A total of 72 village water sources were classified as unimproved (n = 23), semi-improved (n = 37), or improved (n = 12). Based on the estimation of total coliforms, which is a nonspecific bacterial indicator of water quality, all unimproved and semi-improved water sources would be considered as not potable. Escherichia coli, a more precise indicator of faecal pollution, was absent (P < 0.001) in most of the improved water sources. Among 588 queried households, only 38% had access to an "improved" water supply. Sanitation was a serious problem, e.g. fewer than 5% of villagers used latrines and 18% of under-5-year-olds had suffered a recent diarrhoeal illness. The study demonstrates that protection of water sources can improve the hygienic quality of rural water supplies, where disinfection is not feasible. Our findings support the WHO recommendation that E. coli should be the principal microbial indicator for portability of untreated water. Strategies for developing safe water and sanitation systems must include public health education in hygiene and water source protection, practical methods and standards for water quality monitoring, and a resource centre for project information to facilitate programme evaluation and planning.

PIP: This paper presents the results of the quantitative bacterial examination of domestic water supplies in the Lesotho Highlands, the site of a 20-year-old hydroelectric pump. Also studied were the hygiene and health behavior of the community. Water samples from 72 sources in 58 villages and 5 rural health centers were tested for bacterial markers of potability. A total of 23 were classified as unimproved water sources, 37 were semi-improved, and 12 belong to the improved category. Based on the estimation of the total number of coliforms, which is a nonspecific indicator of water quality, all unimproved and semi-improved water sources would be considered as not potable. The study also found that Escherichia coli, a more specific indicator of fecal pollution, was absent (P 0.001) in a majority of the improved water sources. Out of the 588 families surveyed, only 38% claimed they have access to an improved water supply. Moreover, sanitation was found to be a serious concern where less than 5% of the population used latrines and 18% of children under 5 years suffered a recent diarrheal disease. The findings of the study clearly demonstrate that protection of water sources can promote hygienic quality of rural water supplies, where disinfection is not possible. Interventions for developing safe water and sanitation should therefore include public health education in proper hygienic practices and water source protection, practical methods and standards for water potability evaluation, and a resource center for project information.

Human immunodeficiency virus seroprevalence in an occupational cohort in a South African community.

BACKGROUND: In the early years of the worldwide pandemic, there were no reported cases of acquired immunodeficiency syndrome in Lesotho, a small, mountainous country in South Africa. Since 1986, when the first case of acquired immunodeficiency syndrome was identified, reported diagnoses have risen precipitously. The initiation of the Lesotho Highlands Water Project has resulted in the influx of a migrant workforce of predominantly single males into a relatively isolated, mountainous area where human immunodeficiency virus (HIV) was previously unknown. OBJECTIVE: To ascertain the HIV seroprevalence among a cohort of laborers at the Katse Dam construction site in Bokong, Lesotho. METHODS: During the 5-week study period in late 1992, construction workers (age range, 15 to 59 years) who were first-time clinic users for any chief complaint were randomly selected for serological study. Surveillance complied with the Lesotho National AIDS Control Programme guidelines, which required unlinked, anonymous testing. Serum samples were screened by an enzyme-linked immunosorbent assay; the results were confirmed by the Western blot technique. RESULTS: Unlinked, anonymous HIV testing of 486 persons revealed a seroprevalence of 5.3% (26/486; 95% confidence interval, 3.3% to 7.3%). These data contrasted with a 0.8% seroprevalence in a similar age group in nearby villages that surrounded the construction project. CONCLUSIONS: Lesotho, in the early phase of the HIV/acquired immunodeficiency syndrome epidemic in Africa in the 1980s, was seemingly protected by its relative isolation. Grave concern is now warranted as the country is destined to experience a rapid rise in HIV seroprevalence. Increased surveillance, health education opportunities, and aggressive prevention activities at the Katse Dam construction site are imperative to arrest the spread of HIV from construction workers to nearby villagers.