Factoring quality laboratory diagnosis into the malaria control agenda for sub-Saharan Africa

Retrospective data analyses of social and environmental determinants of malaria control for elimination prospects in Eritrea

Background

The present study focuses on both long- and short-term malaria transmission in Eritrea and investigates the risk factors. Annual aggregates of information on malaria cases, deaths, diagnostics and control interventions from 2001 to 2008 and monthly reported data from 2009 to 2017 were obtained from the National Malaria Control Programme. We used a generalized linear regression model to examine the associations among total malaria cases, death, insecticide-treated net coverage, indoor residual spraying and climatic parameters.

Results

Reduction in malaria mortality is demonstrated by the milestone margins of over 97% by the end of 2017. Malaria incidence likewise declined during the period (from 33 to 5 per 1000 population), representing a reduction of about 86% (R² = 0.3) slightly less than the decline in mortality. The distribution of insecticide treated nets generally declined between 2001 and 2014 (R² = 0.16) before increasing from 2015 to 2017, while the number of people protected by indoor residual spraying slightly increased (R² = 0.27). Higher rainfall was significantly associated with an increased number of malaria cases. The covariates rainfall and temperature are a better pair than IRS and LLIN to predict incidences. On the other hand, IRS and LLIN is a more significant pair to predict mortality cases.

Conclusions

While Eritrea has made significant progress towards malaria elimination, this progress should be maintained and further improved. Distribution, coverage and utilization of malaria control and elimination tools should be optimized and sustained to safeguard the gains made. Additionally, consistent annual performance evaluation of malaria indicators would ensure a continuous learning process from gains/threats of epidemics and resurgence in regions already earmarked for elimination.

Advances in malaria elimination in Botswana: a dramatic shift to parasitological diagnosis, 2008-2014

Background: Malaria elimination requires infection detection using quality assured diagnostics and appropriate treatment regimens. Although Botswana is moving towards malaria elimination, reports of unconfirmed cases may jeopardise this effort. This study aimed to determine the proportion of cases treated for malaria that were confirmed by rapid diagnostic testing (RDT) and/or microscopy. Methods: This was a retrospective descriptive study using routine national data from the integrated disease surveillance and case-based surveillance systems from 2008 to 2014. The data were categorised into clinical and confirmed cases each year. An analysis of the data on cases registered in three districts that reported approximately 70% of all malaria cases was performed, stratified by year, type of reporting health facilities and diagnostic method. Results: During 2008-2014, 50 487 cases of malaria were reported in Botswana, and the proportion of RDT and/or blood microscopy confirmed cases improved from 6% in 2008 to 89% in 2013. The total number of malaria cases decreased by 97% in the same period, then increased by 41% in 2013. Conclusion: This study shows that malaria diagnostic tests dramatically improved malaria diagnosis and consequently reduced the malaria burden in Botswana. The study identified a need to build capacity on microscopy for species identification, parasite quantification and guiding treatment choices.

Evaluation of a laboratory quality assurance pilot programme for malaria diagnostics in low-transmission areas of Kenya, 2013

Background

One objective of the Kenya National Malaria Strategy 2009–2017 is scaling access to prompt diagnosis and effective treatment. In 2013, a quality assurance (QA) pilot was implemented to improve accuracy of malaria diagnostics at selected health facilities in low-transmission counties of Kenya. Trends in malaria diagnostic and QA indicator performance during the pilot are described.

Methods

From June to December 2013, 28 QA officers provided on-the-job training and mentoring for malaria microscopy, malaria rapid diagnostic tests and laboratory QA/quality control (QC) practices over four 1-day visits at 83 health facilities. QA officers observed and recorded laboratory conditions and practices and cross-checked blood slides for malaria parasite presence, and a portion of cross-checked slides were confirmed by reference laboratories.

Results

Eighty (96%) facilities completed the pilot. Among 315 personnel at pilot initiation, 13% (n = 40) reported malaria diagnostics training within the previous 12 months. Slide positivity ranged from 3 to 7%. Compared to the reference laboratory, microscopy sensitivity ranged from 53 to 96% and positive predictive value from 39 to 53% for facility staff and from 60 to 96% and 52 to 80%, respectively, for QA officers. Compared to reference, specificity ranged from 88 to 98% and negative predictive value from 98 to 99% for health-facility personnel and from 93 to 99% and 99%, respectively, for QA officers. The kappa value ranged from 0.48–0.66 for facility staff and 0.57–0.84 for QA officers compared to reference. The only significant test performance improvement observed for facility staff was for specificity from 88% (95% CI 85–90%) to 98% (95% CI 97–99%). QA/QC practices, including use of positive-control slides, internal and external slide cross-checking and recording of QA/QC activities, all increased significantly across the pilot (p < 0.001). Reference material availability also increased significantly; availability of six microscopy job aids and seven microscopy standard operating procedures increased by a mean of 32 percentage points (p < 0.001) and 38 percentage points (p < 0.001), respectively.

Conclusions

Significant gains were observed in malaria QA/QC practices over the pilot. However, these advances did not translate into improved accuracy of malaria diagnostic performance perhaps because of the limited duration of the QA pilot implementation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12936-017-1856-2) contains supplementary material, which is available to authorized users.

China-Africa cooperation initiatives in malaria control and elimination

Malaria has affected human health globally with a significant burden of disease, and also has impeded social and economic development in the areas where it is present. In Africa, many countries have faced serious challenges in controlling malaria, in part due to major limitations in public health systems and primary health care infrastructure. Although China is a developing country, a set of control strategies and measures in different local settings have been implemented successfully by the National Malaria Control Programme over the last 60 years, with a low cost of investment. It is expected that Chinese experience may benefit malaria control in Africa. This review will address the importance and possibility of China–Africa collaboration in control of malaria in targeted African countries, as well as how to proceed toward the goal of elimination where this is technically feasible.