Effectiveness of the innovative 1,7-malaria reactive community-based testing and response (1, 7-mRCTR) approach on malaria burden reduction in Southeastern Tanzania

In 2015, a China-UK-Tanzania tripartite pilot project was implemented in southeastern Tanzania to explore a new model for reducing malaria burden and possibly scaling-out the approach into other malaria-endemic countries. The 1,7-malaria Reactive Community-based Testing and Response (1,7-mRCTR) which is a locally-tailored approach for reporting febrile malaria cases in endemic villages was developed to stop transmission and Plasmodium life-cycle. The (1,7-mRCTR) utilizes existing health facility data and locally trained community health workers to conduct community-level testing and treatment.; The pilot project was implemented from September 2015 to June 2018 in Rufiji District, southern Tanzania. The study took place in four wards, two with low incidence and two with a higher incidence. One ward of each type was selected for each of the control and intervention arms. The control wards implemented the existing Ministry of Health programmes. The 1,7-mRCTR activities implemented in the intervention arm included community testing and treatment of malaria infection. Malaria case-to-suspect ratios at health facilities (HF) were aggregated by villages, weekly to identify the village with the highest ratio. Community-based mobile test stations (cMTS) were used for conducting mass testing and treatment. Baseline (pre) and endline (post) household surveys were done in the control and intervention wards to assess the change in malaria prevalence measured by the interaction term of 'time' (post vs pre) and arm in a logistic model. A secondary analysis also studied the malaria incidence reported at the HFs during the intervention.; Overall the 85 rounds of 1,7-mRCTR conducted in the intervention wards significantly reduced the odds of malaria infection by 66% (adjusted OR 0.34, 95% CI 0.26,0.44, p < 0001) beyond the effect of the standard programmes. Malaria prevalence in the intervention wards declined by 81% (from 26% (95% CI 23.7, 7.8), at baseline to 4.9% (95% CI 4.0, 5.9) at endline). In villages receiving the 1,7-mRCTR, the short-term case ratio decreased by over 15.7% (95% CI - 33, 6) compared to baseline.; The 1,7-mRCTR approach significantly reduced the malaria burden in the areas of high transmission in rural southern Tanzania. This locally tailored approach could accelerate malaria control and elimination efforts. The results provide the impetus for further evaluation of the effectiveness and scaling up of this approach in other high malaria burden countries in Africa, including Tanzania

A multiplex qPCR approach for detection of pfhrp2 and pfhrp3 gene deletions in multiple strain infections of Plasmodium falciparum

The rapid and accurate diagnosis of Plasmodium falciparum malaria infection is an essential factor in malaria control. Currently, malaria diagnosis in the field depends heavily on using rapid diagnostic tests (RDTs) many of which detect circulating parasite-derived histidine-rich protein 2 antigen (PfHRP2) in capillary blood. P. falciparum strains lacking PfHRP2, due to pfhrp2 gene deletions, are an emerging threat to malaria control programs. The novel assay described here, named qHRP2/3-del, is well suited for high-throughput screening of P. falciparum isolates to identify these gene deletions. The qHRP2/3-del assay identified pfhrp2 and pfhrp3 deletion status correctly in 93.4% of samples with parasitemia levels higher than 5 parasites/µL when compared to nested PCR. The qHRP2/3-del assay can correctly identify pfhrp2 and pfhrp3 gene deletions in multiple strain co-infections, particularly prevalent in Sub-Saharan countries. Deployment of this qHRP2/3-del assay will provide rapid insight into the prevalence and potential spread of P. falciparum isolates that escape surveillance by RDTs

Epidemiological characterization of malaria in rural southern Tanzania following China-Tanzania pilot joint malaria control baseline survey

Abstract Background Malaria is an important public health problem in Tanzania. The latest national malaria data suggests rebound of the disease in the country. Anopheles arabiensis, a mosquito species renowned for its resilience against existing malaria vector control measures has now outnumbered the endophagic and anthrophilic Anopheles gambiae sensu stricto as the dominant vector. Vector control measures, prophylaxis and case management with artemisinin-based combination therapy (ACT) are the main control interventions. This paper presents and discusses the main findings from a baseline household survey that was conducted to determine malaria parasite prevalence and associated risk exposures prior to piloting the T3-initiative of World Health Organization integrated with Chinese malaria control experience aimed at additional reduction of malaria in the area. Methods The study was conducted from 4 sub-district divisions in Rufiji District, southern Tanzania: Ikwiriri, Kibiti, Bungu, and Chumbi. Malaria transmission is endemic in the area. It involved 2000 households that were randomly selected from a list of all households that had been registered from the area. Residents in sampled households were interviewed on a range of questions that included use of long-lasting insecticidal nets (LLINs) the night prior to the interview and indicators of socio-economic status. Blood drops were also collected on blood slides that were examined for malaria parasites using microscopes. Results The study observed an average malaria parasite prevalence of 13% across the selected site. Its distribution was 5.6, 12.8, 16.7, and 18% from Ikwiriri, Kibiti, Bungu, and Chumbi wards, respectively. The corresponding LLIN use discovered were 57.5% over the district. The highest usage was observed from Ikwiriri at 69.6% and the lowest from Bungu at 46.3%. A statistically significant variation in parasitaemia between socio-economic quintiles was observed from the study. Males were more parasitaemic than females (p value = 0.000). Discussion and conclusion The findings have been discussed in the light of results from Tanzania Demographic and Health Survey-Malaria Indicator Survey, 2015–2016 and other related studies, together with goals and targets set for malaria control. The paper also discusses the observed parasitaemia in relation to reported LLIN use and its distribution by some important factors as they were explored from the study. It has been concluded that malaria burden is now concentrated on the fringes of the settlements where the poorest section of the population is concentrated and LLIN usage is lower than the national average and targets set by national and global malaria control initiatives