Distribution of schistosomiasis and soil transmitted Helminthiasis in Zimbabwe:Towards a national plan of action for control and elimination

Schistosomiasis and STH are among the list of neglected tropical diseases considered for control by the WHO. Although both diseases are endemic in Zimbabwe, no nationwide control interventions have been implemented. For this reason in 2009 the Zimbabwe Ministry of Health and Child Care included the two diseases in the 2009-2013 National Health Strategy highlighting the importance of understanding the distribution and burden of the diseases as a prerequisite for elimination interventions. It is against this background that a national survey was conducted.A countrywide cross-sectional survey was carried out in 280 primary schools in 68 districts between September 2010 and August 2011. Schistosoma haematobium was diagnosed using the urine filtration technique. Schistosoma mansoni and STH (hookworms, Trichuris trichiura, Ascaris lumbricoides) were diagnosed using both the Kato Katz and formol ether concentration techniques.Schistosomiasis was more prevalent country-wide (22.7%) than STH (5.5%). The prevalence of S. haematobium was 18.0% while that of S. mansoni was 7.2%. Hookworms were the most common STH with a prevalence of 3.2% followed by A. lumbricoides and T. trichiura with prevalence of 2.5% and 0.1%, respectively. The prevalence of heavy infection intensity as defined by WHO for any schistosome species was 5.8% (range 0%-18.3% in districts). Only light to moderate infection intensities were observed for STH species. The distribution of schistosomiasis and STH varied significantly between provinces, districts and schools (p<0.001). Overall, the prevalence of co-infection with schistosomiasis and STH was 1.5%. The actual co-endemicity of schistosomiasis and STH was observed in 43 (63.2%) of the 68 districts screened.This study provided comprehensive baseline data on the distribution of schistosomiasis and STH that formed the basis for initiating a national control and elimination programme for these two neglected tropical diseases in Zimbabwe

Malaria Epidemiology and Control in Southern Africa

The burden of malaria has decreased dramatically within the past several years in parts of sub-Saharan Africa, following the scale-up of interventions supported by the Roll Back Malaria Partnership, the President\u27s Malaria Initiative and other partners. It is important to appreciate that the reductions in malaria have not been uniform between and within countries, with some areas experiencing resurgence instead. Furthermore, while interventions have greatly reduced the burden of malaria in many countries, it is also recognized that the malaria decline pre-dated widespread intervention efforts, at least in some cases where data are available. This raises more questions as what other factors may have been contributing to the reduction in malaria transmission and to what extent. The International Center of Excellence for Malaria Research (ICEMR) in Southern Africa aims to better understand the underlying malaria epidemiology, vector ecology and parasite genomics using three contrasting settings of malaria transmission in Zambia and Zimbabwe: an area of successful malaria control, an area of resurgent malaria and an area where interventions have not been effective. The Southern Africa ICEMR will capitalize on the opportunity to investigate the complexities of malaria transmission while adapting to intervention and establish the evidence-base to guide effective and sustainable malaria intervention strategies. Key approaches to attain this goal for the region will include close collaboration with national malaria control programs and contribution to capacity building at the individual, institutional and national levels. © 2011 Elsevier B.V

Prevalence distribution of schistosomiasis and STH among 13, 038 primary school children by settlement in Zimbabwe during 2011 school calendar.

<p>(HD  =  High density; LD  =  Low density)</p

Prevalence of combined schistosomiasis and STH infection by province in Zimbabwe in 2011.

<p><b>*  = </b> Chitungwiza is not a metropolitan province but a town.</p

Stratification of 68 districts in Zimbabwe according to prevalence of heavy infection with any schistosome species (morbidity) and the proposed intervention strategies in 2011.

<p><b>Key:</b></p><p>Complementary strategies  =  Health education, safe water and sanitation, environmental management and snail control.</p

(a) Point prevalence of <i>S. haematobium</i> in 280 primary schools in Zimbabwe during 2011 school calendar.

<p>(<b>b</b>) Point prevalence of <i>S. mansoni</i> in 256 primary schools in Zimbabwe during 2011 school calendar. (<b>c</b>) Point prevalence of hookworms in 256 primary schools in Zimbabwe during 2011 school calendar. (<b>d</b>) Point prevalence of <i>A. lumbricoides</i> in 256 primary schools in Zimbabwe during 2011 school calendar.</p

Prevalence of infection intensities of schistosome species and heavy infection with any schistosome species in Zimbabwe stratified by gender and province in 2011.

<p>*  =  Number examined</p><p><b>¤</b>  =  Chitungwiza is not a metropolitan province but a town</p

Prevalence of schistosomiasis and soil transmitted helminthiasis co-infection combinationsby province in Zimbabwe in 2011.

<p>Prevalence of schistosomiasis and soil transmitted helminthiasis co-infection combinationsby province in Zimbabwe in 2011.</p

Prevalence of schistosome and STH species by province in Zimbabwe in 2011.

<p><b>*  = </b> For each province, the number of participants screened for hookworms, <i>A. lumbricoides</i> and <i>T. trichiura</i> was the same.</p><p><b>**  = </b> The prevalence of parasite species was 0%, 95%CI could therefore not be calculated.</p