By Dr. Derick Pasternak, Malaria Partners International Malaria Science & Research Coordinator
Four articles this month, one co-funded by the Gates Foundation sound the alarm about malaria control programs in the era of COVID-19. Our assurance last month that articles would be posted turned out to be somewhat premature. Please look here for further announcements in that regard. In the meantime, they remain available through my email address, dppaster@gmail.com.
Prevention
A brief article by Makoni M, Mosquito Fighters’ Latest Chemical Weapon May Not Last Long, Science 2020 October, p. 1153 highlights the fact that clothianidine, a substance widely used in African agriculture was recently approved by WHO for addition to bed nets, yet significant populations of Anopheles mosquitoes are already showing resistance, at least in Cameroon. The article claims that WHO is not reacting to this yet, because the resistance data have not been published in a peer-reviewed publication.
In a review focused on bed nets and resistance, Killeen GF, Control of Malaria Vectors and Management of Insecticide Resistance Through Universal Coverage with Next-Generation Insecticide-Treated Nets, Lancet 2020; 395:2394-400, the author reviews some of the history of insecticide resistance and takes WHO to task for what he considers lack of bold proactive recommendations to switch to next generation insecticides in all malarious areas. The article, classified as a “Viewpoint” by the publication, is available.
Iyanda AE, Osayomi T, Boakye KA, & al., Regional Variation and Demographic Factors Associated with Knowledge of Malaria Risk and Prevention Strategies Among Pregnant Women in Nigeria, Women Health, 2020 Apr;60(4):456-472. doi: 10.1080/03630242.2019.1643818. Epub 2019 Jul 22 reports on testing Nigerian pregnant women’s knowledge of preventive strategies. “A wide regional disparity in the knowledge of malaria risks and use of preventive measures exists. Thus, promoting equal access to malaria preventive measures as well as improving knowledge about malaria transmission by mosquitoes should be considered as essential components of ongoing malaria control and elimination efforts in Nigeria.”
Diagnosis
Enane LA, Sullivan KV, Spyridakis E, & al., Clinical Impact of Malaria Rapid Diagnostic Testing at a US Children’s Hospital, J Pediatric Infect Dis Soc 2020 Jul 13;9(3):298-304. doi: 10.1093/jpids/piz022, is a retrospective cohort study of the time it took to treat children diagnosed with laboratory-confirmed diagnosis of malaria before and after the implementation of Rapid Diagnostic Testing, a biochemical method. Average treatment delay was reduced from 10.4 to 0.9 hours, a statistically significant and important change in this cohort of children, most of whom were infected by Plasmodium falciparum. Article available.
A different approach to diagnosis is described in Manescu P, Shaw MJ, Elmi M, & al., Expert-level Automated Malaria Diagnosis on Routine Blood Films with Deep Neural Networks, Am J Hematol, 2020 Aug;95(8):883-891. doi: 10.1002/ajh.25827. Epub 2020 Apr 30. The method described by the authors uses thick film specimens that are subjected to automated scrutiny by a trained Deep Malaria Convolutional Neural Network classifier (DeepMCNN). It has been applied in the West Sub-Saharan region of Africa and “[p]rospective validation of the DeepMCNN achieved sensitivity/specificity of 0.92/0.90 against expert-level malaria diagnosis.” The authors state that this method is of importance for strategies aimed to scale malaria diagnosis in urban regions where daily assessment of thousands of specimens is required.
Malaria remains a leading transfusion associated infectious risk in endemic areas. However, the prevalence of malaria parasitemia has not been well characterized in blood donor populations. Murphy KJ, Conroy AL, Ddungu H, & al., Malaria Parasitemia Among Blood Donors in Uganda, Transfusion 2020 May;60(5):955-964. doi: 10.1111/trf.15775. Epub 2020 Apr 13, report on a study to determine the prevalence of Plasmodium in red blood cell (RBC) and whole blood (WB) units after the rainy season in Uganda. “Malaria parasitemia among asymptomatic, eligible blood donors in two regions of Uganda was 15.4%; 87.7% (135/154) of infections were with P. falciparum, while P. malariae and P. ovale were also detected. There were 4.3% of blood donors who had mixed infection with multiple species.” Older donors, female donors, repeat donors, and those donating in the vicinity of Kampala had a lower prevalence of Plasmodium parasitemia.
Treatment
Announcing the beginning of a series on treatment of malaria in pregnant women, Saito M, Briand V, Min AM, & al., Deleterious Effects of Malaria in Pregnancy on the Developing Fetus: A Review on Prevention and Treatment with Antimalarial Drugs, Lancet Child Adolesc Health, 2020 Oct 4(10):761-774. doi: 10.1016/S2352-4642(20)30099-7, aims to summarise the adverse effects of malaria in pregnancy on the fetus and how the current drug treatment and prevention strategies can alleviate these effects. Although evidence supports the safety and treatment efficacy of artemisinin-based combination therapies in the first trimester, these therapies have not been recommended by WHO for the treatment of malaria at this stage of pregnancy.
A different type of article is the personal testimonial of an Irish medical student about her experience in a pediatrics service in Uganda. It is found in DeSousa E, Stories from the Fields; Meeting Malaria, Am J Trop Med Hyg 2020, 102(3):489-90. It also relates how prophylaxis was ineffective in her own situation. Article available.
Campaigns
Four articles this month examine the impact of our current pandemic on malaria campaigns and eventually on the prevalence of the disease. They are:
Hogan AB, Jewell BL, Sherrard-Smith E, & al., Potential Impact of the COVID-19 Pandemic on HIV, Tuberculosis, and Malaria an Low-Income and Middle-Income Countries: A Modelling Study, Lancet Glob Health, 2020 Sep;8(9):e1132-e1141. doi: 10.1016/S2214-109X(20)30288-6. Epub 2020 Jul 13 was funded in part by Gates Foundation.
Rogerson SJ, Beeson JG, Laman M, & al., Identifying and Combating the Impacts of COVID-19 on Malaria, BMC Med 2020 Jul 30;18(1):239. doi: 10.1186/s12916-020-01710-x.
Weiss TJ, Bertozi-Villa A, Rumisha SF, & al., Indirect Effects of the COVID-19 Pandemic on Malaria Intervention Coverage, Morbidity, and Mortality in Africa: A Geospatial Modeling Analysis, Lancet Infect Dis 2020 Sep 21, sttps://doi.org/10.1016/S1473-3099(20)30-7003