Impact case study database

The World Health Organisation has a roadmap (2020 Roadmap for Neglected Tropical Disease) for member states to eliminate schistosomiasis as a public health problem by 2030.

Based on the results of Professor Mutapi’s research that confirmed nationwide predominance in distribution of schistosomiasis and a lesser extent of STH, preventive chemotherapy strategies were determined and recommended for the elimination of these two specific NTDs in Zimbabwe.

“On a national scale, Professor Mutapi has been involved in the genesis, planning and implementation of Zimbabwe’s helminth control programme started in 2012.” [5.1]

In September 2012, the Zimbabwe Ministry of Health formulated a national NTD control policy, 5-year action plan and implemented school-based mass drug administration, including schistosomiasis treatment, targeting primary and secondary school children across the country based on this mapping exercise. Five of the six annual mass drug administrations (MDAs) occurred within the REF2021 impact period [5.1].

Crucially, Zimbabwe’s control programme recommended treating all children annually irrespective of the regional prevalence of infection. This is in contrast to the WHO preventive chemotherapy guidelines that recommend the frequency of treatment based on community/regional infection level, i.e. high risk communities should be treated annually, whereas those at lower risk should be treated every two years or twice within a child’s school career.

“This work provided the evidence base leading to the WHO recommendations, thus correcting a significant and long-standing health inequity, and making ~50 million pre-school African children eligible for schistosomiasis treatment.” [5.1].

Disease: The treatment program has not only reached 100% of the target population, but has reduced infection and disease level in school children from a national level of 32% to 0% [5.1].

Figure 1 Changes in prevalence at national level from MDA 1 to MDA 6.

Annual MDAs were carried out in Zimbabwe from September 2012. Five of the six annual MDAs occurred within the REF2021 impact period (10/2013, 01/2015, 11/2015, 11/2016, 11/2017). For the six years of annual MDA, monitoring and evaluation of the treatments were conducted [3.4]. After six rounds of annual MDA, Zimbabwe surpassed the WHO recommended 75% coverage to over 90% coverage and decreased national prevalence of schistosomiasis (infection and disease) from 32% to <1% in school children [5.1]. The treatment coverage increased each year peaking at 90% in 2016, well above the 75% coverage for schoolchildren set by the WHO for the “2020 Roadmap” for schistosomiasis [5.2]. Annual assessment in sentinel sites throughout the country showed that schistosome infection and disease level decreased significantly after each round of treatment from the pre-treatment levels in the same year. Most notably, both urogenital schistosomiasis infection and morbidity prevalence reduced from 32% at baseline in 2012 to 0% in 2017, and infection intensity reduced and 28.75 eggs/10ml urine to 0 in the same time period. Intestinal schistosomiasis prevalence and intensity reduced from 4.6% and 0.28 eggs/25mg of stool to 0% and 0 eggs respectively [3.4], [all the treatment coverage data are publicly available on the ESPEN database 5.3, 5.4 & 5.5]. Thus, the control programme significantly reduced schistosome infection and morbidity in the school children, illustrated in Figure 1 [3.4], moving the national schistosome prevalence in school-aged children from moderate to low by WHO classification.

In 2018, Zimbabwe spent USD15,392,840.14, on drugs to treat NTDs (intestinal worms, schistosomiasis, lymphatic filariasis and trachoma) as part of the MDA programmes [5.6, pg14], placing Zimbabwe in the top 8 African countries based on the value of treatments. In 2018, 95,300,000 people received preventative chemotherapy for schistosomiasis, 76,200,000 million were school-aged children and the remaining 19,100,000 were adults [5.7 i-iii].

Due to the success of the MDAs, the need for an integrated strategy for eliminating schistosomiasis in Zimbabwe involving treatment, sanitation and education was highlighted in The End Fund, “Breaking the Cycle of neglect” review.

“To develop robust elimination strategies it is vital for Zimbabwe to gain a better understanding of the distribution of these diseases in adults and preschool-age children.” [5.8]

“There is also an urgent need to improve education on NTDs within the primary school curriculum on hygiene and sanitation practices.” [5.8]

Daily life: To capture impact at the individual child level as well as overall impact in schools, a community impact evaluation [5.9] was carried out in late October 2019. Perception of the MDA programmes for helminth control by the affected populations influences compliance and future designs of the programmes. Public perception of Zimbabwe’s National Helminth Control Program (2012-2017) was determined with a specific focus on schistosomiasis in the school children treated with praziquantel, school teachers and village health workers (VHW).

The study enrolled 409 children from Grades 6 and 7 who had the full benefit of the 6 years of MDA from 2012 to 2017. 36 schoolteachers and 22 VHW serving the schools were also recruited. The evaluation focused on the perceived impact on heath, school attendance and performance and Knowledge Attitudes and Practice (KAP). Overall, 84% of the children responded that their awareness of schistosomiasis (transmission, disease, treatment and infection avoidance) had improved because of participating in the MDAs. Of the 151 children self-diagnosed with schistosomiasis, 74% reported that their health had improved following treatment with praziquantel. This included resolution of haematuria, painful urination, sore stomach, tiredness and falling asleep during class lessons. The children and teachers reported improvements in both pupil school attendance and performance at school as well as an increase in health seeking behaviour for schistosomiasis treatment in-between MDAs.

The majority of VHW (96%) reported improvement in handwashing behaviour, schistosomiasis awareness (96%) and treatment uptake (91%) within the community. However, only 59% and 50% of the VHW reported improvement in toilet use and clean water use respectively, within their communities.

This study indicated that the community perceived that the MDA programme had improved the health of children, their school attendance, school performance and awareness of schistosomiasis. The VHW also perceived that the MDA program had improved the community KAP. Perception of helminth MDA programs by the affected populations influences compliance and therefore, affects the success of the programme. This evaluation determined the perception of Zimbabwe’s National Helminth Control Program with a specific focus on schistosomiasis in the school children treated with praziquantel, schoolteachers and village health workers (VHWs) [5.9].

NTD Mapping in Zimbabwe and elsewhere: Due to the success of the Zimbabwe National NTD programme, other countries in Africa have adopted the mapping strategy [3.3] and subsequent implementation of control programmes for schistosomiasis, STH and other NTDs [5.1].

“We conducted a national survey to map the current distribution of schistosomiasis and for the first time, to map the distribution of STH in Zimbabwe” [3.3].

Mapping of NTDs is now complete in 41 (87%) countries in the African region [5.7, pg 5]. In the REF impact period (2014 & 2015), 22 African countries including Mauritiana, Liberia, Chad, Niger, Nigeria, Benin, Namibia, Madagascar & DR Congo were mapped for NTDs by the WHO-AFRO mapping project.

“A total of 75 million school aged children (SAC) were treated in 2017, representing an unprecedented coverage of 69.4% from 29 countries that reported data in a timely manner.” [5.10, pg 5].

Mapping was ongoing in Ethiopia and Angola and was soon to start in South Africa, South Sudan and Algeria. The AFRO Mapping project, a joint effort of WHO's African Regional Office and NTD Support Centre, is nearing completion of Phase I: the district-wide assessments for preventative chemotherapy against NTDs (lymphatic filariasis, onchocerciasis, soil-transmitted helminthiasis, schistosomiasis and trachoma). Building on countries' earlier mapping efforts, 85% of districts in the AFRO region now are fully mapped for these diseases.

This impact covers over 87% of countries in Africa and an estimated 620 Million people at risk of disease by NTDs in Africa. The mapping of NTDs across Africa has allowed countries to works towards effective regional elimination programmes and improve accuracy of the incidence of NTDs. There will be cost savings through safe and integrated mass drug administration, and through ending of unnecessary treatments.

More recently, Professor Mutapi’s group extended the findings of the mapping exercise to develop a strategy for mapping schistosome infection in preschool children, a current knowledge gap identified by the WHO. The strategy developed by Professor Mutapi and her group uses data from the surveys in school age children such as that highlighted here for an inexpensive approach applicable in poor resource settings obviating the need for surveying young children [3.6].

As a direct result of the Mutapi group’s research [3.2], preschool aged children are included in the 2012 Zimbabwe NTD control policy. Zimbabwe implemented this policy throughout the REF period, and consequently these children have been treated annually in local clinics out with the MDAs [3.5] [5.1].

“Professor Mutapi and her team showed that pre-school children are exposed, infected and suffer from schistosome morbidity. She also showed that treatment with praziquantel was safe and efficacious in this age group. This work provided the evidence base leading to the WHO recommendations, thus correcting a significant and long-standing health inequity, and making ~50 million pre-school African children eligible for schistosomiasis treatment.” Director Epidemiology and Disease Control, Ministry for Health and Child Welfare, Zimbabwe [5.1]