Science and Research Report for June 2022

By Dr. Derick Pasternak, Malaria Science & Research Coordinator, Malaria Partners International 

Last month this column included a reference to an unsigned Lancet editorial, entitled Malaria in 2022: A Year of Opportunity, without much commentary other than it was a call to action. Two articles this month are of similar genre and instead of trying to categorize them, they are mentioned here, so that they receive maximum attention from the reader.

The first is Jagannathan P & Kakuru A, Malaria in 2022: Increasing Challenges, Cautious Optimism, Nat Commun, 2022 May 13; 13(1):2678, doi: 10.1038/s41467-022-30133-w. It states that the following aspects of the current status are grounds for optimism: “…the approval of the world’s first malaria vaccine and results from novel vaccine candidates and trials testing innovative combinatorial interventions.”  It looks not just at the RTS,S vaccine, which is currently in use and will be licensed to an Indian manufacturer in the near future, but also beyond it to R21, which it regards as more promising.  Just as important are the references to the development of triple therapy and the development of new antimalarials that are effective against artemisinin-resistant Plasmodia.

April Monroe, Ph.D. of Johns Hopkins University and her colleagues recently published far encompassing Reflections on the 2021 World Malaria Report and the Future of Malaria Control, Malaria J, 2022 May 27, vol 21 art 154, malariajournal.biomedcentral.com/articles/10.1186/s12936-022-04178-7. It “presents key insights from the 2021 World Malaria Report and reflections on the future trajectories: it was informed by an in-depth discussion with leading malaria experts from the World Health Organization (WHO), the Bill & Melinda Gates Foundation, and the U.S. President’s Malaria Initiative (PMI). The discussion took place during the 34th edition of the Ifakara Master Classes, held virtually on December 15th, 2021.”

Prevention:

Vaccines 

Mulamba C & al. discuss yet another approach to vaccine development; targeting Plasmodial gametocytes in order to mitigate illness and prevent transmission to a new vector, in Evaluation of the Pfs25-IMX313/Matrix-M Malaria Transmission-Blocking Candidate Vaccine in Endemic Settings, Malaria J, 2022 Jun 2, vol 21 art 159, doi: 10.1186/s12936-022-04173-y. The authors urge “that institutions in low and middle-income settings should be supported to conduct first-in-human vaccine trials in order to stimulate innovative research and reduce the overdependence on developed countries for research and local interventions against many diseases of public health importance.”

While the development of anti-Plasmodial vaccines is hailed not only in the articles in the introduction above but elsewhere, three articles this month highlight the phenomenon of vaccine hesitancy, which is apparently not confined to political or other opposition in this country in another context.  The articles delve into some of the social, religious, and economic issues that lead a significant number of individuals to shy away from making their children available for vaccination. The articles are Asmare G, Willingness to Accept Malaria Vaccine Among Caregivers of Under-5 Children in Southwest Ethiopia: a Community Based Cross-Sectional Study, Malaria J, 2022 May 12, vol 21 art 146, doi: 10.1186/s12936-022-04164-z and Immurana M & al., Determinants of Willingness to Accept Child Vaccination Against Malaria in Ghana, Int J Health Plann Manage, 2022 May; 37(3):1439-1453. doi: 10.1002/hpm.3406, as well as Darkwa S & al., “I Would Have to Sell Things in Order to Get the Money”: A Qualitative Exploration of Willingness to Pay for the RTS,S/AS01 Malaria Vaccine in the Volta Region, Ghana, PLoS One, 2022 Jun 8; 17(6):e0268009. doi: 10.1371/journal.pone.0268009.

Vector control and protection from vectors

Mosquito epidemiology is very much the topic in articles this month, starting with an article that focuses on the methods to collect the malaria vectors, Namango IH & al., The Centres for Disease Control Light Trap (CDC-LT) and the Human Decoy Trap (HDT) Compared to the Human Landing Catch (HLC) for Measuring Anopheles Biting in Rural Tanzania, Malaria J, 2022 Jun 11, vol 21 art 181, doi: 10.1186/s12936-022-04192-9.

Two articles call attention to a species that arrived in Africa not very long ago, has apparently established itself in the Northeast part of the continent and demonstrates habits that differ from other Anopheles species. Mnzawa A & al., Anopheles stephensi in Africa Requires a More Integrated Response, Malaria J, 2022 May 31, vol 21 art 156, doi: 10.1186/s12936-022-04197-4 and Hamlet A & al., The Potential Impact of Anopheles stephensi Establishment on the Transmission of Plasmodium falciparum in Ethiopia and Prospective Control Measures, BMC Med, 2022 Apr 20; 20(1):135. doi: 10.1186/s12916-022-02324-1 extrapolate from known characteristics of this species and experience with it in Djibouti that their spread may greatly increase the prevalence of falciparum malaria, unless “large increases in vector control interventions” are implemented.

Additional unhappy results are reported in Sangbakembi-Ngounou C & al., Diurnal Biting of Malaria Mosquitoes in the Central African Republic Indicates Residual Transmission May Be “Out of Control,” Proc Natl Acad Sci U S A, 2022 May 24; 119(21):e2104282119. doi: 10.1073/pnas.2104282119. “By performing mosquito collections 48-h around the clock, both indoors and outdoors, and by modeling biting events using circular statistics, [they] evaluated the full daily rhythmicity of biting in urban Bangui, Central African Republic… [and] unexpectedly ∼20 to 30% of indoor biting occurred during daytime…  Prevalence of Plasmodium falciparum in the nighttime- and daytime-biting mosquitoes was the same.” This means that the usual protective measures are coming up short.

Turning to the more customary African vectors, Ngowo HS & al., Using Bayesian State-Space Models to Understand the Population Dynamics of the Dominant Malaria Vector, Anopheles funestus in Rural Tanzania, Malaria J, 2022 Jun 3, vol 21 art 161, doi: 10.1186/s12936-022-04189-4 states that this species, unlike An. gambiae, is predicted to be less likely to demonstrate seasonal fluctuations in transmitting the parasite. This conclusion is supported by Kahamba NF & al., who state in Using Ecological Observations to Improve Malaria Control in Areas Where Anopheles funestus is the Dominant Vector, Malaria J, 2022 Jun 2, vol 21 art 158, doi: 10.1186/s12936-022-04198-3, that the species is “well-adapted to sustain its populations even during dry months and can support year-round malaria transmission.”

Somewhat uncertain are the conclusions of Musiba RM & al. in Outdoor Biting and Pyrethroid Resistance as Potential Drivers of Persistent Malaria Transmission in Zanzibar, Malaria J, 2022 Jun 7, vol 21 art 172, doi: 10.1186/s12936-022-04200-y, insofar as “of 704 malaria vectors collected across 135 households, … all mosquitoes were negative for the malaria parasite.” Yet they claim that the “study highlights the need to implement novel interventions and/or adaptations of strategies that can target outdoors biting mosquitoes.”

An interesting aspect of pyrethroid resistance is explored by Ososro JK & al. in Insecticide Resistant Anopheles gambiae Have Enhanced Longevity but reduced Reproductive Fitness and a Longer First Gonotrophic Cycle, Sci Rep, 2022 May 23: 12(1):8646, doi.org/10.1038/s41598-022-12753-w. Resistant female mosquitoes demonstrated “lower fecundity … and net reproductive rate” compared to controls that were susceptible to the chemical, even though they lived longer.

Long-lasting insecticide-treated nets are the subject of two papers.  Mosha JF & al. conclude that of the three potential additives to pyrethroid, “chlorfenapyr LLINs provided significantly better protection than pyrethroid-only LLINs against malaria in an area with pyrethroid-resistant mosquitoes, and the additional cost of these nets would be considerably below plausible cost-effectiveness thresholds.” The article is Effectiveness And Cost-Effectiveness Against Malaria of Three Types of Dual-Active-Ingredient Long-Lasting Insecticidal Nets (LLINs) Compared with Pyrethroid-Only LLINs In Tanzania: A Four-Arm, Cluster-Randomised Trial, Lancet,  2022 Mar 26; 399(10331):1227-1241, doi: 10.1016/S0140-6736(21)02499-5.  The use, or rather the significant non-use (by over 45% of households studied) of distributed LLINs in Nigeria is the topic of Uhomoibhi P & al., Drivers of Long-Lasting Insecticide-Treated Net Utilisation and Parasitaemia Among Under-Five Children in 13 States with High Malaria Burden in Nigeria, PLoS One, 2022 May 6; 17(5):e0268185. doi: 10.1371/journal.pone.0268185. The article mentions factors that mitigate toward higher use.

Despite the fact that the population studied by Hasabo EA & al., Treatment-Seeking Behaviour, Awareness and Preventive Practice Toward Malaria in Abu Ushar, Gezira State, Sudan: A Household Survey Experience from a Rural Area, Malaria J, 2022 Jun 11, vol 21 art 182, doi: 10.1186/s12936-022-04207-5 was said to have good understanding of malaria, their utilization of LLIN was approximately 45%.  They recommend an “interventional programme,” without specifying its nature.

Azizi S & al., Implementing OECD GLP Principles for the Evaluation of Novel Vector Control Tools: A Case Study With Two Novel LLINs, SafeNet^® and SafeNet NF^®, Malaria J, 2022 Jun 11, vol 21 art 183, doi: 10.1186/s12936-022-04208-4 is a description of the laboratory testing process that meets Good Laboratory Practices criteria.

The cost-effectiveness of using a particular “third generation indoor residual product” is explored by Yukich J & al., Incremental Cost and Cost-Effectiveness of the Addition of Indoor Residual Spraying with Pirimiphos-Methyl in Sub-Saharan Africa Versus Standard Malaria Control: Results of Data Collection and Analysis in the Next Generation Indoor Residual Sprays (Ngenirs) Project, an Economic-Evaluation, Malaria J, 2022 Jun 11, vol 21 art 185, doi: 10.1186/s12936-022-04160-3. They conclude that that product “is expected to deliver acceptable value for money in a broad range of sub-Saharan African malaria transmission settings.”

Chemoprophylaxis

de Cola MA & al., Impact of Seasonal Malaria Chemoprevention on Prevalence of Malaria Infection in Malaria Indicator Surveys in Burkina Faso and Nigeria, BMJ Glob Health, 2022 May; 7(5):e008021. doi: 10.1136/bmjgh-2021-008021 reiterate what other studies have found, namely that the practice reduces the odds of getting malaria by 6 to 59 month old recipients of seasonal chemoprophylaxis.

Diagnosis:

In the Gambia thorough diagnostics were performed on asymptomatic schoolchildren by Mooney JP & al. They report in Dry Season Prevalence of Plasmodium falciparum in Asymptomatic Gambian Children, with a Comparative Evaluation of Diagnostic Methods, Malaria J, 2022 Jun 7, vol 21 art 171, doi: 10.1186/s12936-022-04184-9 that unlike microscopy, which detected parasites in 2.9% of the children studied, a sensitive PCR test detected a prevalence of 10.2%, most with extremely low parasite count.

Likewise, in Western Kenya, Otambo WO & al. report in Risk Associations of Submicroscopic Malaria Infection in Lakeshore, Plateau and Highland Areas of Kisumu County in Western Kenya, PLoS One, 2022 May 16; 17(5):e0268463. doi: 10.1371/journal.pone.0268463 that among 1,777 apparently healthy volunteers, 3.7% were found to have parasitemia by microscopy but 18% by PCR testing. “Blood smears results were exclusively positive for P. falciparum, whereas RT-PCR also detected P. malariae and P. ovale mono- and co-infections.”  This paper then explores geographic correlates of the rates of infection.

“New studies report asymptomatic infections are responsible for up to half of new transmissions, often sliding under the radar and sabotaging efforts of malaria elimination programs,” according to Henderson E, htpps://www.news-medical.net/news/20220505/crucial-discovery-could-inform-potential-strategies-to-control- malaria-transmission.aspx, downloaded 13 May 2022. She quotes Studniberg, S.I. & al., Molecular Profiling Reveals Features of Clinical Immunity and Immunosuppression in Asymptomatic P. falciparum Malaria. Molecular Systems Biology, 2022, doi: 10.15252/msb.202110824 to the effect that many patients with chronic low-grade parasitemia have suppressed immune system, thereby tolerating the low grade infection, but they are nonetheless community reservoirs of infection and should be diagnosed and treated to avoid spread of the disease.

Marino A & al. emphasize the need for rapid diagnosis in cases of cerebral malaria in Updates in Central Nervous System Malaria: Literature Review and Considerations, Curr Opin Infect Dis, 2022 Jun 1; 35(3):255-261. doi: 10.1097/Qco.0000000000000829.

Treatment:

Treatment guidelines

Like many other papers from a variety of African countries, Gindola Y & al., Adherence to National Malaria Clinical Management and Testing Guidelines in Selected Private Clinics of Gambela Town, Gambela Region, Ethiopia: A Mixed Method Study, Malaria J, 2022 Jun 3, vol 21 art 164, doi: 10.1186/s12936-022-04206-6 reports insufficient adherence to national treatment guidelines by private clinics even by unaudited self-admission on surveys.  {This is not at all surprising, given that guidelines are often not followed by health care professionals in fields other than malaria, even in well-developed countries – Editorial Comment.}

Therapeutic efficacy

Ethiopia is one African country where infection with Plasmodium vivax is prevalent, if not as frequent as falciparum malaria. Radical cure for both infections, where they coexist, is potentially complicated because of the more complex life cycle of P. vivax. Thriemer K & al., Reducing the Risk of Plasmodium vivax After falciparum Infections in Co-Endemic Areas – A Randomized Controlled Trial, Trials, 2022 May 18; 23(1):416, doi:10.1186/s13063-022-06364-z offers a “rationale for universal use of radically curative treatment in patients with P. falciparum malaria even in the absence of detectable P. vivax parasitaemia in areas that are co-endemic for both species.” This means adding a 7-day course of primaquine to the standard treatment for falciparum malaria.

Rectal artesunate is available to a number of primary care providers for rapid treatment of children severely ill with malaria. Brunner NC & al., Prereferral Rectal Artesunate and Referral Completion Among Children with Suspected Severe Malaria in the Democratic Republic of the Congo, Nigeria and Uganda, BMJ Glob Health, 2022 May; 7(5):e008346. doi: 10.1136/bmjgh-2021-008346 report that referral for definitive treatment of these children is not universal (between 48 and 67%) in the three countries studied.  They conclude that the findings lead to “legitimate concerns that the roll-out of RAS may lead to lower referral completion in children who were administered prereferral RAS. To ensure that community-based programmes are effectively implemented, barriers to referral completion need to be addressed at all levels.”

Drug resistance

“Malaria caused by Plasmodium vivax has the potential to affect 2·5 billion people globally, accounting for 88% of people at risk of malaria overall; however, due to its more severe course, Plasmodium falciparum receives the most attention, according to Khattak AA & al. in their paper, Antimalarial Drug Resistance – Is It Time to Re-Evaluate Plasmodium falciparum Othologous Genes? Lancet Microbe, 2022 May 20:S2666-5247(22)00, doi: 10.1016/s2666-5247(22)00118-5.  The authors aver that resistance in P. vivax is difficult to evaluate, though the abstract is silent on the subject of othologous genes.

Moss S & al., How Has Mass Drug Administration with Dihydroartemisinin-Piperaquine Impacted Molecular Markers of Drug Resistance? A Systematic Review, Malaria J, 2022 Jun 11, vol 21 art 186, doi: 10.1186/s12936-022-04181-y is, in part, a review of whether mass drug administration campaigns are followed by the WHO-recommended surveillance of “molecular markers of resistance.” Of 96 papers included in this review, only 20 analyzed these molecular markers.

Two papers are case reports of individual patients with multi-drug resistant falciparum malaria.  They are Oboh M & al., Multiple Plasmodium falciparum Drug Resistance Polymorphisms Identified in a Pregnant Woman with Severe Malaria and a Concomitant Spontaneous Abortion in Cross River, Nigeria, West Africa, Malaria J, 2022 Jun 3, vol 21 art 160, doi: 10.1186/s12936-022-04176-9 and Sacomboio ENM & al., Evaluation of Blood Cell Count Parameters as Predictors of Treatment Failure of Malaria in Angola: An Observational Study, PLoS One, 2022 May 5; 17(5):e0267671. doi: 10.1371/journal.pone.0267671.

Other treatments

Birkholtz L-M & al., Transmission-Blocking Drugs for Malaria Elimination, Trends Parasitol, 2022 May;38(5):390-403. doi: 10.1016/J.Pt.2022.01.011 proposes “development of new antimalarials with transmission-blocking activity to guide drug discovery for malaria elimination.”

Kalkman LC  & al. remind readers that drug therapy alone is insufficient treatment in Fluid Therapy for Severe Malaria, Lancet Infect Dis, 2022 Jun; 22(6):E160-E170. doi: 10.1016/S1473-3099(21)00471-0.

Botanicals

Pradhan D & al. purport to report on the Isolation and Structure Elucidation of a Steroidal Moiety from Withania somnifera and in silico Evaluation of Antimalarial Efficacy Against Artemisinin Resistance Plasmodium falciparum kelch13 Protein, J Biomol Struct Dyn, 2022 May 18:1-14, doi: 10.1080/07391102.2022.2077448, however, the abstract is unrevealing as to the content of the article. {Withania somnifera, or Indian ginseng, is used in traditional Indian Ayurvedic medicine for thousands of years to ease pain and inflammation, treat insomnia, and boost nutrition, along with other conditions – Google}

Raidron C & al. selected eight indigenous Namibian “medicinal plants which are used traditionally for the treatment of tuberculosis (TB), malaria, and associated symptoms…The aim of this study was to evaluate the antiplasmodial and antimycobacterial activities of the organic and aqueous crude extracts of different plant parts.” They report in Antiplasmodial and Antimycobacterial Activities of Crude and Lead-Like Enhanced Extracts from Namibian Medicinal Plants, J Ethnopharmacol. 2022 May 16:115389, doi: 10.1016/j.jep.2022.115389 that Sarcocaulon marlothii yielded various extracts with antiplasmodial activity. They attempted to identify the substance but were able only to state that it “may be a hydroxycinnamic acid derivative.” {Sarcocaulon marlothii, native to Namibia, is called “Bushman’s candle” in English, according to plantsam.com}

Campaigns:

Kaboré JMT & al. “aimed to identify potential facilitators or barriers at the community level to inform a health district-wide implementation of multiple first-line therapies (MFT) as a new strategy for uncomplicated malaria case management.” Attitudes, Practices, and Determinants of Community Care-Seeking Behaviours for Fever/Malaria Episodes in the Context of the Implementation Oof Multiple First-Line Therapies for Uncomplicated Malaria in the Health District of Kaya, Burkina Faso, Malaria J, 2022 May 30, vol 21 art 155, doi: 10.1186/s12936-022-04180-z “showed appropriate knowledge about malaria and positive community care-seeking behaviour at health centres for fever/malaria episodes. This could potentially facilitate the implementation of a MFT pilot programme in the district.”

A stratification of malaria risk was performed by Cissoko M & al. in Mali. As reported in Stratification at the Health District Level for Targeting Malaria Control Interventions in Mali, Sci Rep, 2022 May 18; 12(1):8271. doi: 10.1038/s41598-022-11974-3, “[t]argeted malaria control interventions were selected based on spatial heterogeneity of malaria incidence, malaria prevalence in children, vector resistance distribution, health facility usage, child mortality, and seasonality of transmission. … Risk stratification identified 12 health districts in very low transmission areas, 19 in low transmission areas, 20 in moderate transmission areas, and 24 in high transmission areas. Low health facility usage and increased vector resistance were observed in high transmission areas. Eight intervention combinations were selected for implementation.”

The effectiveness of campaigns very much depends on the receptivity of the target population. Aberese-Ako M & al. analyzed articles published in English over 12 years on the subject of Malaria in Pregnancy initiatives.  As reported in Motivators and Demotivators to Accessing Malaria in Pregnancy Interventions in Sub-Saharan Africa: A Meta-Ethnographic Review, Malaria J, 2022 Jun 3, vol 21 art 170, doi:  10.1186/s12936-022-04205-7, they recognized four categories each of motivating and demotivating factors.  Their inevitable conclusions are: “Health system gaps need to be strengthened in order to ensure that MiP interventions become accessible to women. Additionally, health managers need to involve communities in planning, designing and implementing malaria interventions for pregnant women.”

Asale A & al., The Combined Impact of LLINs, House Screening, and Pull-Push Technology of Improved Malaria Control and Livelihoods in Rural Ethiopia: Study Protocol for Household Randomised Controlled Trial, BMC Public Health, 2022 May 10; 22(1):930. doi: 10.1186/s12889-022-12919-1 is an announcement of an upcoming trial with a description of the protocol.

Although Smithuis FM & White NJ, Spend Wisely to Eliminate Malaria, Lancet Infect Dis, 2022 Jun; 22(6):e171-e175. doi: 10.1016/S1473-3099(21)00256-5 is focused on Southeast Asia, its analysis of the economics of antimalaria campaigns is relevant to many areas in sub-Saharan Africa. They state:  “New, labour intensive, vertical approaches to malaria elimination … should not be promoted as these are … costly, and unlikely to be sustainable in the most remote areas where malaria prevalence is highest. Instead, the focus should be on reducing the malaria burden more rapidly in the remaining localized high transmission foci with proven effective interventions, including mass drug administration. Well-supported community-based health workers are the key operatives in controlling malaria, but their remit should be broadened to sustain the uptake of their services as malaria declines. This strategy is a sustainable evolution, which will improve rural health care while ensuring progress towards malaria elimination.”

Epidemiology:

Makenga G & al. found that over 25% of schoolchildren in a district in Tanzania had asymptomatic malaria infections. Their article, Attributable Risk Factors for Asymptomatic Malaria and Anaemia and Their Association with Cognitive and Psychomotor Functions in Schoolchildren of North-Eastern Tanzania, PLoS One, 2022 May 26; 17(5):e0268654, doi: 10.1371/journal.pone.0268654, also reports anemia, “stunting,” and impaired psychomotor function among many  of these children.

Likewise, in Uganda, Rek J & al, Asymptomatic School-Aged Children Are Important Drivers of Malaria Transmission in a High Endemicity Setting in Uganda, J Infect Dis, 2022 May 17;jiac169, doi: 10.1093/infdis/jiac169 reports that in the population studied, “symptomatic and asymptomatic infections were estimated to contribute to 5.3% and 94.7% of the infectious reservoir, respectively. School-aged children (5-15 years-old) contributed to 50.4% of transmission events and were important drivers of malaria transmission.”

Tilaye T & al. studied another population for asymptomatic malaria. High Asymptomatic Malaria Among Seasonal Migrant Workers Departing to Home from Malaria Endemic Areas in Northwest Ethiopia, Malaria J, 2022 Jun 11, vol 21 art 184, doi: 10.1186/s12936-022-04211-9 reports that among 1208 seasonal migrant workers interviewed and tested during their departure from farm sites to their homes, 17.5% were found to have malaria. 70+% of them were infected by P. falciparum and 28+% by P. vivax.

On the subject of P. vivax, Angrisano F & Robinson LJ, assert in Plasmodium vivax – How Hidden Reservoirs Hinder Global Malaria Elimination, Parasitol Int, 2022 Apr; 87:102526. doi: 10.1016/j.parint.2021.102526 that this parasite now causes 14 million new infections yearly, though not predominantly in Sub-Saharan Africa (see also Khattak AA & al. above.)

Three articles review various aspects of malaria epidemiology in Ethiopia (a source of many of these types of articles over the months). They are Almaw A & al., Prevalence of Malaria and Associated Factors Among Symptomatic Pregnant Women Attending Antenatal Care at Three Health Centers in North-West Ethiopia, PLoS One, 2022 Apr 7; 17(4):E0266477. doi: 10.1371/journal.pone.0266477,

Warkaw YM & al., Spatial Pattern and Predictors of Malaria in Ethiopia: Application of Auto Logistics Regression, PLoS One, 2022 May 20; 17(5):E0268186. doi: 10.1371/journal.pone.0268186, and Abebaw A & al., The Prevalence of Symptomatic and Asymptomatic Malaria and its Associated Factors in Debre Elias District Communities, Northwest Ethiopia, Malaria J, 2022 Jun 3, vol 21 art 167, doi: 10.1186/s12936-022-04194-7.

Togo is a small country in West Africa. Nonetheless, Kombate G & al., Regional Heterogeneity of Malaria Prevalence and Associated Risk Factors Among Children Under Five in Togo: Evidence from a National Malaria Indicators Survey, Malaria J, 2022 Jun 3, vol 21 art 168, doi: 10.1186/s12936-022-04195-6 demonstrates great variability in infection rates, “ranging from 7.0% in the Lomé Commune region to 47.1% in the Plateaux region. In multivariate analysis, statistically significant differences between regions persisted.”

Along with other papers published on the subject, Heuschen A-K & al., Impact of the COVID-19 Pandemic on Malaria Cases in Health Facilities in Northern Ghana: A Retrospective Analysis of Routine Surveillance Data, Malaria J, 2021 May 15, vol 21., doi: 10.1186/s12936-022-04154-1 concludes that “the COVID-19 pandemic affects the malaria burden in health facilities of northern Ghana.” Interestingly, while the infection rate among pregnant women increased, there was a reduction of other populations presenting for treatment.

Okunlola OA & Oyeyemi OT, Malaria Transmission in Africa: Its Relationship with Yellow Fever and Measles, PLoS One, 2022 May 4; 17(5):E0268080  doi: 10.1371/journal.pone.0268080 reports that “malaria incidence, death due to malaria, measles and yellow fever data were sourced from the WHO database. … Malaria varied negatively with measles cases but positively with yellow fever.” These associations were statistically significant.

Masimbi O & al. analyzed the cost of malaria treatment in communities and health centers in Rwanda.  Close to 300,000 cases were reviewed in three districts. A Cost Analysis of the Diagnosis and Treatment of Malaria at Public Health Facilities and Communities in Three Districts in Rwanda, Malaria J, 2022 May 15, vol 21 art 150, doi: 10.1186/s12936-022-04158-x found that “[s]imple malaria cases managed at health centres and district hospitals were more than two-fold … and more than eight-fold … higher, respectively, than those managed in the community.” The cost of caring for complicated cases, of course exceeded these higher costs even more.