Mapping of schistosomiasis and soil-transmitted helminthiasis in the regions of Littoral, North-West, South and South-West Cameroon and recommendations for treatment

Abstract

BackgroundThe previous nationwide mapping of schistosomiasis and soil-transmitted helminthiasis (STH) in Cameroon was conducted 25 years ago. Based on its results, mass drug administration (MDA) of praziquantel was limited to the three northern regions and few health districts in the southern part of Cameroon. In 2010, we started the process of updating the disease distribution in order to improve the control strategies. Three of the ten regions of Cameroon were mapped in 2010 and the data were published. In 2011, surveys were conducted in four additional regions, i.e. Littoral, North-West, South and South-West.MethodsParasitological surveys were conducted in March 2011 in selected schools in all 65 health districts of the four targeted regions, using appropriate research methodologies, i.e. Kato-Katz and urine filtration.ResultsThe results showed significant variation of schistosomiasis and STH prevalence between schools, villages, districts and regions. Schistosoma haematobium was the most prevalent schistosome species, with an overall prevalence of 3.2%, followed by S. mansoni (3%) and S. guineensis (1.2%). The overall prevalence of schistosomiasis across the four regions was 7.4% (95% CI: 6.7-8.3%). The prevalence for Ascaris lumbricoides was 19.5% (95% CI: 18.3-20.7%), Trichuris trichiura 18.9% (95% CI: 17.7-20.1%) and hookworms 7.6% (95% CI: 6.8-8.4%), with an overall STH prevalence of 32.5% (95% CI: 31.1-34.0%) across the four regions. STH was more prevalent in the South region (52.8%; 95% CI: 48.0-57.3%), followed by the South-West (46.2%; 95% CI: 43.2-49.3%), the North-West (35.9%; 95% CI: 33.1-38.7%) and the Littoral (13.0%; 95% CI: 11.3-14.9%) regions.ConclusionsIn comparison to previous data in 1985–87, the results showed an increase of schistosomiasis transmission in several health districts, whereas there was a significant decline of STH infections. Based on the prevalence data, the continuation of annual or bi-annual MDA for STH is recommended, as well as an extension of praziquantel in identified moderate and high risk communities for schistosomiasis.

Prevalence and intensity of Ancylostoma duodenale and Necator americanus infestations in school children from the Lolodorf health district (Cameroon)

“…Overall prevalence of hookworm infestation recorded in the 541 children was low (5.1%). This finding confirmed the report by [11] Tchuen-Tchuente et al (2013) who noted a decline in the prevalence of human soil-transmitted helminths in the South province of Cameroon. The result was probably due to mass drug administration (MDA) campaigns implemented by the Cameroonian MOH [11] (Tchuen-Tchuente et al, 2013).…”

“…Species identification is usually done using morphological characteristics of third-stage larvae, from eggs in faecal-culture [10] (WHO, 1991). The present study was undertaken to search whether A duodenale was present in south Region of Cameroon, a zone where the prevalence and parasite loads of STHs are very high [11] Study site: Lolodorf health district is located in the South Region of Cameroon near the western coast of Africa in the Atlantic littoral evergreen forest (10 • 28 ′ E, 3 • 07 ′ N). the climate is made-up of four seasons: a long dry season that extend from November to mid-March; a long rainy season that extends from mid-August to November; a short dry season that extends from mid-June to mid-August and a short rainy season that extends from mid-March to mid-June.…”

Biomphalaria camerunensis as a viable alternative intermediate host for Schistosoma mansoni in southern Cameroon

“…This study was conducted in Cameroon in a context where S. mansoni transmission is persisting, with the creation of new foci [3, 4]. This situation might have been driven by a number of reasons [18], and adaptation of a ‘foreign’ parasite to an intermediate host appears essential to the creation of new foci for disease expansion.…”

“…In addition to the mass administration of praziquantel to school-aged children (5–14 years) since 2005, the schistosomiasis control strategy in Cameroon also relies on education of communities about the disease and risks of infection, and the promotion of hygiene and environmental sanitation. These actions have contributed to significantly reducing the prevalence of this disease in several foci [3, 4]. Despite these control measures, the current epidemiological situation reveals the persistence of schistosomiasis in some foci, and the emergence of new foci of the disease [3–5].…”

Bladder outlet obstruction; a rare complication of the neglected schistosome, Schistosoma haematobium: two case reports and public health challenges

“…A study carried out in 2013 by Tchuenté et al showed an increase in transmission foci of schistosomiasis compared to previous data in 1985–1987 [19]. …”