Changing Patterns of Soil-Transmitted Helminthiases in Zanzibar in the Context of National Helminth Control Programs

Abstract

Abstract. Helminth control programs have been implemented in Zanzibar for over a decade. In June/July 2007, ~6 months after the last school-based anthelmintic treatment, a cross-sectional survey was carried out in two schools, and results were compared with data obtained in the same schools in 1994. Multiple stool samples collected from 368 school children were subjected to the Kato-Katz, Koga agar plate, and Baermann methods. The prevalence of Trichuris trichiura , hookworm, Ascaris lumbricoides, and Strongyloides stercoralis was 46.6%, 21.6%, 16.9%, and 10.2%, respectively. Infection intensities were generally low. Compared with 1994, the prevalence of S. stercoralis , hookworm, A. lumbricoides, and T. trichiura decreased by 81.0%, 80.5%, 70.6%, and 48.6%, respectively. Infection intensities decreased by > 95% for all helminth species studied. Our study confirms that preventive chemotherapy successfully reduces the level and intensity of helminth infections. To consolidate achievements made, additional control measures such as health education and environmental sanitation are needed.

Soil-transmitted helminth infections and risk factors in preschool children in southern rural Lao People's Democratic Republic

“…10,34 Additional health promotion on hygienic practices is essential to assure long-term benefits. 35 In Lao PDR, mass distribution of anthelminthic medicines in schools was started a few years ago. In 2006, schoolchildren from 13 of the total 17 provinces had been covered once per year, including Savannakhet province.…”

Albendazole and Mebendazole Administered Alone or in Combination with Ivermectin againstTrichuris trichiura: A Randomized Controlled Trial

“…The study was conducted in Unguja, Zanzibar Island, Tanzania, from March through May 2009. Stool samples were collected from children attending schools in Kinyasini and Kilombero, where soil-transmitted helminthiasis is highly endemic [12]. Both schools are located in district North A, 30-40 km northeast of Zanzibar Town.…”

“…The prevalence of T. trichiura infections was conservatively estimated to be 30% [12], and the compliance for stool submission was assumed to be 90% per sample. Hence, we estimated that ∼2000 subjects were needed to identify 600 T. trichiurainfected individuals.…”

“…In Zanzibar, control programs have significantly reduced the prevalence and intensity of soil-transmitted helminthiasis [12]. However, in contrast to A. lumbricoides and hookworm, the prevalence of T. trichiura infections has remained high [12,13].…”

“…However, in contrast to A. lumbricoides and hookworm, the prevalence of T. trichiura infections has remained high [12,13]. Against this background, we were motivated to assess the efficacy and safety of albendazole and mebendazole combined with ivermectin against T. trichiura and to compare treatment outcomes with standard monotherapies.…”