Mapping of Schistosomiasis and Soil-Transmitted Helminthiasis in the Regions of Centre, East and West Cameroon

Schistosomiasis and soil-transmitted helminthiasis (STH) are a major public health problem in Cameroon. The national control strategy of these diseases was based on historical data collected 25 years ago, which might be outdated in some situations due to several factors including control activities, improved or degraded sanitation and hygiene, socio-economic improvement and disease transmission dynamics. To help planning, improving control strategies and evaluation of control activities, there was a need to update the distribution of schistosomiasis and STH. We conducted parasitological surveys in three regions of Cameroon, i.e. Centre, East and West. Our results showed a significant decrease of STH infection prevalence and intensities in all these three regions, in comparison to previous mapping data, with an overall decline of prevalence from 81.1–93% to 10.5–46.6%. These results show the positive impact of annual deworming campaigns, and illustrate the progressive success of the national programme for the control of schistosomiasis and STH in Cameroon. Furthermore, our results showed an increase of the number of high transmission foci of schistosomiasis, and allowed identifying new health districts requiring mass treatment with praziquantel, and those where deworming should be reinforced

Comparison of prevalence of schistosomiasis and STH between 1980s and 2010.

<p>Note:</p><p>*Figures in brackets represent the 95% confidence intervals.</p

Comparative maps of the overall soil-transmitted helminthiasis prevalence in the three surveyed regions of Cameroon.

<p>Prevalence distribution in 1985–1987 (A) and in 2010 (B).</p

Prevalence of schistosomiasis and STH by age in the three surveyed regions in Cameroon.

<p>A few outliers below 5 or above 17 years old are not plotted.</p

Prevalence of schistosomiasis by school in the three surveyed regions of Cameroon.

<p>(A) <i>S. haematobium</i>, (B) <i>S. mansoni</i>, and (C) <i>S. guineensis</i>.</p

Comparative maps of the overall schistosomiasis prevalence in the three surveyed regions of Cameroon.

<p>Prevalence distribution in 1985–1987 (A) and in 2010 (B).</p

Prevalence of soil-transmitted helminthiasis by school in the three surveyed regions of Cameroon.

<p>(A) <i>A. lumbricoides</i>, (B) <i>T. trichiura</i>, and (C) Hookworm infections.</p

Prevalence and intensity of infections in school children in the three surveyed regions in Cameroon.

<p>Note:</p><p>*Figures in brackets represent the 95% confidence intervals.</p><p>**eggs/10 ml urine for <i>S. haematobium</i> intensity of infection; light, moderate and heavy infections was categorized according to the WHO recommendations (Ref #26); <i>S. guineensis</i> infection was categorized using the recommendations for <i>S. mansoni</i>.</p

Arithmetic mean intensity of infection of schistosomiasis and STH by age in the surveyed regions.

<p>A few outliers below 5 or above 17 years old are not plotted. Error bars represent 95% CI.</p