Tropical Health Matters

Over the coming three days the Malaria Vaccine Implementation Programme (MVIP) Advisory Group in its capacity as SAGE/MPAG Working Group will conduct a full evidence review of the RTS,S/AS01 malaria vaccine and develop proposed recommendations for Strategic Advisory Group of Experts (SAGE) on Immunization and MPAG. This comes on the heels of the recent 74th World Health Assembly Resolution that, “Urges Member States to step up the pace of progress through plans and approaches that are consistent with WHO’s updated global malaria strategy and the WHO Guidelines for malaria. It calls on countries to extend investment in and support for health services, ensuring no one is left behind; sustain and scale up sufficient funding for the global malaria response; and boost investment in the research and development of new tools.”

The large scale pilot intervention of the RTS,S/AS01 malaria vaccine started two years ago in selected districts in three countries countries: Ghana, Kenya and Malawi.  For example, “Two years on from the launch of a pilot programme, more than 1.7 million doses of the world’s first malaria vaccine have been administered in Ghana, benefitting more than 650,000 children with additional malaria protection.” WHO says that, “Insights generated by the pilot implementation will inform a WHO recommendation on broader use of the vaccine across sub-Saharan Africa,” which will then be considered by global advisory bodies for immunization and malaria, i.e. the SAGE and MPAG.

WHO is asking the Working Group to address the following question, “Does the additional evidence on the feasibility, safety and impact of the RTS,S/AS01 vaccine support a WHO recommendation for use of the vaccine in children in sub-Saharan Africa beyond the current pilot implementation?” WHO has set the following meeting objectives:

1. To examine and provide input to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) evidence profiles of the quality of the evidence used to inform the recommendations;
2. To review and interpret the evidence, with explicit consideration of the overall balance of benefits and harms;
3. To formulate recommendations – in alignment with the endorsed 2019 RTS,S Framework for Decision – taking into account benefits, harms, values and preferences, feasibility, equity, acceptability, resource requirements and other factors, as appropriate.

Hopefully decisions will be forthcoming soon so that planning can get underway to address immunization as part of the overall malaria elimination effort.

In 2001 the first Africa Malaria Day (AMD) was observed. The opportunity to mark progress and exhort increased efforts for the continent continued through 2007. Then in 2008, the concept of World Malaria Day (WMD) took over, though it could not be denied that the bulk of malaria morbidity, mortality and intervention still was focused on African countries. Other countries have made progress such as the recent certification of malaria elimination in Argentina and El Salvador, but twenty years after the first AMD/WMD, Africa is still leading the way for creative, sustained intervention against the disease, despite threats to resources from economic downturns and new pandemic diseases.

Below we go straight to Africa to share activities and observances of WMD 2021 from Jhpiego’s African Malaria Technical Officers. After reading through, please watch “Jhpiego Leaves No One Behind | World Malaria Day, 2021″ on YouTube.

“Saramed” from Guinea reports that Guinea, like other countries in the world, celebrates World Malaria Day under the theme: ” Zero Malaria, Draw a Line on Malaria “. We are currently conducting the following activities:

• Lectures and debates on malaria in medical faculties and health schools;
• Animation of debate programs on malaria in public and private radios and televisions of the country,
• Advocacy and sensitization of religious and other influential people
• Carrying out a package of activities (administration of IPT to pregnant women who have missed their ANC appointment, community distribution of LLINs, screening and treatment of confirmed cases, awareness raising on malaria) in high incidence localities.

These activities is in line with the WHO approach of “high burden, high impact”.

Noella Umulisa reports that the WMD celebration took place in Eastern Province, in Bugesera district in the Mareba sector. Due to COVID-19 pandemic ,only 100 persons were invited to the event.This year’s the national theme is “Zero Malaria starts with me”.

Key activities during the event included …

• Visit of breeding sites under sentinel surveillance
• Visit of indoor residual spraying (IRS) sites
• Launching of the Awareness of the population using drones on the ongoing IRS campaign in this time of COVID-19
• Song by CHWs
• Certificate to Integrated Vector Management (IVM) Training of Trainers who will train others up to village level
• Speech of the Director General ,the guest of honor.

From Burkina Faso, Yousseff Sawadogo and Moumouni Bonkoungou shared photos of the celebration that featured a giant Insecticide-Treated  Net, a speech by the US Ambassador, a malaria song composed by a nurse, an official speech by the President of the National Assembly, and national recognition given to one of the current Jhpiego staff members, Thiery Ouedraogo, who at one time also served as director of the national malaria control program. He was decorated by the country’s authorities as a knight of the order of merit.

Bright Orgi from Jhpiego’s TiPToP malaria in pregnancy project in Nigeria ?? shared photos from a series of compound meetings in the community to mark WMD 2021. The meetings focused on malaria prevention and treatment. Provided opportunities to rural communities to ask questions on malaria issues. Here we can see that observance of WMD must be taken to the people who actually suffer from malaria and need to be actively involved in its solution. Deo Cibinda from the Democratic Republic of the Congo share photos of a national celebration, seen to the left.

Finally, As Kristen Vibbert noted, “These are such amazing World Malaria Day stories. I’m so heartened to see all of these great country efforts to remind everyone of how the fight against malaria must continue despite the Covid-19 pandemic.”  Charles Wanga tweeted, “We know how to defeat #malaria. But that’s not enough. We must do more to save pregnant women and children from the deadly scourge. This #WorldMalariaDay and everyday, because@Jhpiego leaves no one behind in our fight to #EndMalaria for good in Africa, and everywhere”

Recent news and abstracts explore malaria on three continents. Genetic aspects of malaria are studied in Haiti as well in Malaysia. Use of fish to control malaria carrying mosquitoes are successful in India. The movement toward malaria elimination is examined in Cape Verde. Finally, Non-invasive diagnostic tests are recognized/rewarded by NIH. Read more by following the links below.

NIH Awards Prize to Hemex Health’s Non-Invasive Sickle Cell, Malaria, Anemia Rapid Test (“SMART”) Diagnostic Technology

Researchers from Hemex Health, Medtronic plc, Case Western Reserve University, and the University of Nebraska Medical Center’s International Foundation Against Infectious Disease in Nigeria (IFAIN) were awarded 3rd place and $100,000 in the NIH Technology Accelerator Challenge.  Code named, SMART (Sickle, Malaria, Anemia, Rapid Test), the system includes non-invasive diagnostics for sickle cell, malaria, and anemia. The project seeks to build on Hemex Health’s Gazelle® platform, which currently includes minimally invasive tests (using a drop of blood) for malaria, the detection and quantification of hemoglobin variants, as well as for total hemoglobin for anemia determination.

The non-invasive test will screen for anemia, malaria, and sickle cell disease using an optical finger sensor similar to the way blood oxygen is measured. An advantage of combining the non-invasive and minimally invasive diagnostics is, when needed, more diagnostic information and confirmation is available on the same platform. The goal is a one-minute, $0.25 non-invasive malaria, sickle cell, and anemia test. “The world desperately needs easy-to-use diagnostic technologies with the flexibility needed to meet viruses and diseases in every corner of the planet,” said Ms. White.

Controlling Mosquitoes: Ramanathapuram district inches closer to malaria-free status

Steps taken by the Ramanathapuram district administration to control mosquito breeding for the last five years has enableed the district inch closer to being declared a ‘malaria-free district, with only one malarial fever case having been reported till September, this year. Last year, the district reported 43 cases.

One of the initiatives is to bring guppy fish from the Ayyankulam tank in Tiruvannamalai district and let them into all wells and tanks of the districts in 3:1 ratio (3 familes/one male). The fish thrives, eating the mosquito larvae and eggs and the incidence of malaria came down in the district.

Updates on malaria epidemiology and profile in Cabo Verde from 2010 to 2019: the goal of elimination

Located in West Africa, Cabo Verde is an archipelago consisting of nine inhabited islands. Malaria has been endemic since the settlement of the islands during the sixteenth century and is poised to achieve malaria elimination in January 2021. The aim of this research is to characterize the trends in malaria cases from 2010 to 2019 in Cabo Verde as the country transitions from endemic transmission to elimination and prevention of reintroduction phases. All confirmed malaria cases reported to the Ministry of Health between 2010 and 2019 were extracted from the passive malaria surveillance system.

A total of 814 incident malaria cases were reported in the country between 2010 and 2019, the majority of which were Plasmodium falciparum. Cabo Verde has made substantial gains in reducing malaria burden in the country over the past decade and are poised to achieve elimination in 2021. However, the high mobility between the islands and continental Africa, where malaria is still highly endemic, means there is a constant risk of malaria reintroduction. Characterization of imported cases provides useful insight for programme and enables better evidence-based decision-making to ensure malaria elimination can be sustained.

Genetic analysis reveals unique characteristics of Plasmodium falciparum parasite populations in Haiti

With increasing interest in eliminating malaria from the Caribbean region, Haiti is one of the two countries on the island of Hispaniola with continued malaria transmission. While the Haitian population remains at risk for malaria, there are a limited number of cases annually, making conventional epidemiological measures such as case incidence and prevalence of potentially limited value for fine-scale resolution of transmission patterns and trends. In this context, genetic signatures may be useful for the identification and characterization of the Plasmodium falciparum parasite population in order to identify foci of transmission, detect outbreaks, and track parasite movement to potentially inform malaria control and elimination strategies.

This study evaluated the genetic signals based on analysis of 21 single-nucleotide polymorphisms (SNPs) from 462 monogenomic (single-genome) P. falciparum DNA samples extracted from dried blood spots collected from malaria-positive patients reporting to health facilities in three southwestern Haitian departments (Nippes, Grand’Anse, and Sud) in 2016.

437 of the 462 samples shared high levels of genetic similarity–at least 20 of 21 SNPS–with at least one other sample in the dataset. These results revealed patterns of relatedness suggestive of the repeated recombination of a limited number of founding parasite types without significant outcrossing. These genetic signals offer clues to the underlying relatedness of parasite populations and may be useful for the identification of the foci of transmission and tracking of parasite movement in Haiti for malaria elimination.

Epidemiology of malaria among pregnant women during their first antenatal clinic visit in the middle belt of Ghana

A total of 1655 pregnant Ghanaian women aged 18 years and above with a gestational age of 13–22 weeks, who attended an antenatal care (ANC) clinic for the first time, were consented and enrolled into the study. A structured questionnaire was used to collect socio-demographic and obstetric data and information on use of malaria preventive measures. Venous blood (2 mL) was collected before sulfadoxine-pyrimethamine administration. Malaria parasitaemia and haemoglobin concentration were determined using microscopy and an automated haematology analyser, respectively.

One out of five pregnant women attending their first ANC clinic visit in an area of perennial malaria transmission in the middle belt of Ghana had Plasmodium falciparum infection. Age???25 years, multigravid, educated to high school level or above, and in household with higher socio-economic status were associated with a lower risk of malaria parasitaemia. Majority of the infections were below 1000 parasites/µL and with associated anaemia. There is a need to strengthen existing malaria prevention strategies to prevent unfavourable maternal and fetal birth outcomes in this population.

Genetic diversity of circumsporozoite protein in Plasmodium knowlesi isolates from Malaysian Borneo and Peninsular Malaysia

Understanding the genetic diversity of candidate genes for malaria vaccines such as circumsporozoite protein (csp) may enhance the development of vaccines for treating Plasmodium knowlesi. Hence, the aim of this study is to investigate the genetic diversity of non-repeat regions of csp in P. knowlesi from Malaysian Borneo and Peninsular Malaysia.
The phylogenetic analysis revealed indistinguishable clusters of P. knowlesi isolates across different geographic regions, including Malaysian Borneo and Peninsular Malaysia.

The csp non-repeat regions are relatively conserved and there is no distinct cluster of P. knowlesi isolates from Malaysian Borneo and Peninsular Malaysia. Distinctive variation data obtained in the C-terminal non-repeat region of csp could be beneficial for the design and development of vaccines to treat P. knowlesi.

The American Journal of Tropical Medicine and Hygiene has several new articles on malaria. Abstracts are shared. Two articles examine the role of travel in malaria transmission, both cross-border and rural-urban. Another considers the effect on pharmacokinetics of lumefantrine due to gut bacteria. In Uganda indoor spraying has reduced transmission, but asymptomatic cases remain among children. The challenges of asymptomatic malaria to elimination efforts is also examined in India. Links to the articles are found below.

Evidence of Microbiome–Drug Interaction between the Antimalarial Lumefantrine and Gut Microbiota in Mice

The antimalarial drug lumefantrine exhibits erratic pharmacokinetics. Intersubject variability might be attributed, in part, to differences in gut microbiome–mediated drug metabolism. We assessed lumefantrine disposition in healthy mice stratified by enterotype to explore associations between the gut microbiota and lumefantrine pharmacokinetics. Gut microbiota enterotypes were classified according to abundance and diversity indices from 16S rRNA sequencing. Pharmacokinetic parameters were computed using noncompartmental analysis. Two distinct enterotypes were identified.

Maximal concentration (C max) and total drug exposure measured as the area under the drug concentration–time curve (AUC0–24) differed significantly between the groups. The mean and standard deviation of C max were 660 ± 220 ng/mL versus 390 ± 59 ng/mL (P = 0.02), and AUC0–24 was 9,600 ± 2,800 versus 5,800 ± 810 ng × h/mL (P = 0.01). In healthy mice intragastrically dosed with the antimalarial drug lumefantrine in combination with artemether, lumefantrine exposure was associated with gut bacterial community structure. Studies of xenobiotic–microbiota interactions can inform drug posology and elucidate mechanisms of drug disposition.

Malaria Transmission, Infection, and Disease following Sustained Indoor Residual Spraying of Insecticide in Tororo, Uganda

Tororo, a district in Uganda with historically high malaria transmission intensity, has recently scaled up control interventions, including universal long-lasting insecticidal net distribution in 2013 and 2017, and sustained indoor residual spraying (IRS) of insecticide since December 2014. We describe the burden of malaria in Tororo 5 years following the initiation of IRS. We followed a cohort of 531 participants from 80 randomly selected households in Nagongera subcounty, Tororo district, from October 2017 to October 2019. Mosquitoes were collected every 2 weeks using CDC light traps in all rooms where participants slept, symptomatic malaria was identified by passive surveillance, and microscopic and submicroscopic parasitemia were measured every 4 weeks using active surveillance. Over the 2 years of follow-up, 15,780 female anopheline mosquitos were collected, the majority (98.0%) of which were Anopheles arabiensis.

The daily human biting rate was 2.07, and the annual entomological inoculation rate was 0.43 infective bites/person/year. Only 38 episodes of malaria were diagnosed (incidence 0.04 episodes/person/year), and there were no cases of severe malaria or malarial deaths. The prevalence of microscopic parasitemia was 1.9%, and the combined prevalence of microscopic and submicroscopic parasitemia was 10.4%, each highest in children aged 5–15 years (3.3% and 14.0%, respectively). After 5 years of intensive vector control measures in Tororo, the burden of malaria was reduced to very low transmission levels. However, a significant proportion of the population remained parasitemic, primarily school-aged children with submicroscopic parasitemia, providing a potential reservoir for malaria transmission.

Malaria Diagnosed in an Urban Setting Strongly Associated with Recent Overnight Travel: A Case–Control Study from Kampala, Uganda

Malaria is frequently diagnosed in urban Kampala, despite low transmission intensity. To evaluate the association between recent travel out of Kampala and malaria, we conducted a matched case–control study. Cases were febrile outpatients with a positive malaria test; controls were febrile outpatients with a negative test. For every two cases, five controls were selected, matching on age. Data were collected on recent overnight travel out of Kampala (past 60 days), destination and duration of travel, and behavioral factors, including sleeping under an insecticide-treated net (ITN) during travel. From July to August 2019, 162 cases and 405 controls were enrolled. The locations of residence of cases and controls were similar. More controls were female (62.7% versus 46.3%, P < 0.001). Overall, 158 (27.9%) participants reported recent overnight travel.

Travelers were far more likely to be diagnosed with malaria than those who did not travel (80.4% versus 8.6%, OR 58.9, 95% CI: 23.1–150.1, P < 0.001). Among travelers, traveling to a district not receiving indoor residual spraying of insecticide (OR 35.0, 95% CI: 4.80–254.9, P < 0.001), no ITN use (OR 30.1, 95% CI: 6.37–142.7, P < 0.001), engaging in outdoor activities (OR 22.0, 95% CI: 3.42–141.8, P = 0.001), and age < 16 years (OR 8.36, 95% CI: 2.22–56.2, P = 0.03) were associated with increased odds of malaria. Kampala residents who traveled overnight out of the city were at substantially higher risk of malaria than those who did not travel. For these travelers, personal protection measures, including sleeping under an ITN when traveling, should be advocated.

Prevalence of Asymptomatic Malaria Parasitemia in Odisha, India: A Challenge to Malaria Elimination

The prevalence of malaria in India is decreasing, but it remains a major concern for public health administration. The role of submicroscopic malaria and asymptomatic malaria parasitemia and their persistence is being explored. A cross-sectional survey was conducted in the Kandhamal district of Odisha (India) during May–June 2017. Blood samples were collected from 1897 individuals for screening of asymptomatic parasitemia. Samples were screened using rapid diagnostic tests (RDTs) and examined microscopically for Plasmodium species. Approximately 30% of randomly selected samples (n = 586) were analyzed using real-time PCR (qPCR), and the genetic diversity of Plasmodium falciparum was analyzed.

The prevalence of Plasmodium species among asymptomatic individuals detected using qPCR was 18%, which was significantly higher than that detected by microscopy examination (5.5%) or RDT (7.3%). Of these, 37% had submicroscopic malaria. The species-specific prevalence among asymptomatic malaria-positive cases for P. falciparum, Plasmodium vivax, and mixed infection (P. falciparum and P. vivax) by qPCR was 57%, 29%, and 14%, respectively. The multiplicity of infection was 1.6 and 1.2 for the merozoite surface protein-1 gene (msp1) and (msp2), respectively. Expected heterozygosity was 0.64 and 0.47 for msp1 and msp2, respectively. A significant proportion of the study population, 105/586 (18%), was found to be a reservoir for malaria infection, and identification of this group will help in the development of elimination strategies.

Travel Is a Key Risk Factor for Malaria Transmission in Pre-Elimination Settings in Sub-Saharan Africa: A Review of the Literature and Meta-Analysis

By sustaining transmission or causing malaria outbreaks, imported malaria undermines malaria elimination efforts. Few studies have examined the impact of travel on malaria epidemiology. We conducted a literature review and meta-analysis of studies investigating travel as a risk factor for malaria infection in sub-Saharan Africa using PubMed. We identified 22 studies and calculated a random-effects meta-analysis pooled odds ratio (OR) of 3.77 (95% CI: 2.49–5.70), indicating that travel is a significant risk factor for malaria infection.

Odds ratios were particularly high in urban locations when travel was to rural areas, to more endemic/high transmission areas, and in young children. Although there was substantial heterogeneity in the magnitude of association across the studies, the pooled estimate and directional consistency support travel as an important risk factor for malaria infection.

News and abstracts provide more on the surge of malaria in Mali. COVID-19 complicates malaria elimination in Southeast Asia. Peace Corps health care for volunteers in Comoros is questioned. Malaria risk in Ecuador is investigated. Risk maps are used/not used in three Sub-Saharan countries. The potential of microbiological control is considered. More information on each topic is available in the links provided.

Health workers raise alarm over surge in malaria cases, deaths in Mali

More details emerge on malaria in northern Mali. Medical workers in Mali raised an alarm over a surge in malaria cases which has seen at least 23 people killed by the disease in just the past one week. About 13,000 malaria cases were reported in the north by medical workers between September 21 and 27, representing an 88 percent increase in cases from the previous week. 59 people have died of malaria in the nation’s northern region since the beginning of the year, according to the ministry, which confirmed the deaths of the 23 people over the aforementioned September period.

Will COVID-19 hamper ASEAN’s fight to eliminate malaria?

Although progress elsewhere in the world has been slow, in the Asia-Pacific, deaths due to the mosquito-borne disease have dropped by 70% and cases have dropped by 22%. Within ASEAN, those figures—according to the Asia Pacific Leaders Malaria Alliance (APLMA)—are 92% and 67% respectively. The battle to eliminate malaria is continually evolving with different species of disease-carrying mosquitoes and parasites presenting new challenges. In 2008, a new strain of malaria that proved resistant to the anti-malarial drug artemisinin, nicknamed “super malaria”, emerged in Cambodia. It spread through the Greater Mekong region into Laos, Thailand and Vietnam and by 2017, it had developed resistance to another drug, piperaquine.

In response, scientists and researchers focused their resources on areas where the new strain was present and were making headway towards eliminating it. COVID-19 could threaten that progress. “We have enough evidence from the Ebola epidemic to suggest how progress on malaria elimination could be derailed and we are seeing some clear warnings now,” APLMA/APMEN commented. Historically, malaria cases have risen in countries where healthcare is interrupted due to conflict, disaster and war.

Peace Corps faces questions over death of volunteer from Inverness

By Sheryl Gay Stolberg of the New York Times reported that the Peace Corps, which suspended all operations for the first time in its history as the novel coronavirus raced around the globe, is facing renewed questions about the quality of its medical care — in particular, after the death of a 24-year-old volunteer from undiagnosed malaria — as it prepares to send volunteers back into the field.

An investigation by the Peace Corps inspector general documented a string of problems with Heiderman’s care. Her doctor had “limited training in tropical medicine,” the investigation found, and failed to test for malaria, which would have revealed that Heiderman had been infected by the deadliest malaria parasite. The Peace Corps was also using outdated 2006 guidelines for malaria, which did not reflect the current standard of care.

Anopheline and human drivers of malaria risk in northern coastal Ecuador

Understanding local anopheline vector species and their bionomic traits, as well as related human factors, can help combat gaps in protection. In San José de Chamanga, Esmeraldas, at the Ecuadorian Pacific coast, anopheline mosquitoes were sampled by both human landing collections (HLCs) and indoor-resting aspirations (IAs) and identified using both morphological and molecular methods.

Among 222 anopheline specimens captured, based on molecular analysis. The exophagic feeding of anopheline vectors in San Jose de Chamanga, when analysed in conjunction with human behaviour, indicates a clear gap in protection even with high LLIN coverage. The lack of indoor-resting anophelines suggests that indoor residual spraying (IRS) may have limited effect. The presence of asymptomatic infections implies the presence of a human reservoir that may maintain transmission.

How useful are malaria risk maps at the country level?

This study examined the perceptions of decision-makers in Kenya, Malawi and the Democratic Republic of Congo. Declining malaria prevalence and pressure on external funding have increased the need for efficiency in malaria control in sub-Saharan Africa (SSA). Modelled Plasmodium falciparum parasite rate (PfPR) maps are increasingly becoming available and provide information on the epidemiological situation of countries. However, how these maps are understood or used for national malaria planning is rarely explored. In this study, the practices and perceptions of national decision-makers on the utility of malaria risk maps, showing prevalence of parasitaemia or incidence of illness, was investigated.

Three different types of maps were used to show malaria epidemiological strata: malaria prevalence using a PfPR modelled map (Kenya); malaria incidence using routine health system data (Malawi); and malaria prevalence using data from the most recent Demographic and Health Survey (DRC). In Kenya the map was used to target preventative interventions, including long-lasting insecticide-treated nets (LLINs) and intermittent preventive treatment in pregnancy (IPTp), whilst in Malawi and DRC the maps were used to target in-door residual spraying (IRS) and LLINs distributions in schools. Maps were also used for operational planning, supply quantification, financial justification and advocacy. Findings from the interviews suggested that decision-makers lacked trust in the modelled PfPR maps when based on only a few empirical data points (Malawi and DRC). Despite the availability of national level modelled PfPR maps in all three countries, they were only used in one country.

Infection of highly insecticide-resistant malaria vector Anopheles coluzzii with entomopathogenic bacteria

This study found that Chromobacterium violaceum reduces its survival, blood feeding propensity and fecundity of mosquitoes in Burkina Faso. The study was motivated by the concern that malaria eradication will not be achieved without the introduction of novel control tools. Microbiological control might be able to make a greater contribution to vector control in the future. The interactions between bacteria and mosquito make mosquito microbiota really promising from a disease control perspective.
Methods

To assess entomopathogenic effects of C. violaceum infection on mosquitoes, three different types of bioassays were performed in laboratory. These bioassays aimed to evaluate the impact of C. violaceum infection on mosquito survival, blood feeding and fecundity, respectively. During bioassays mosquitoes were infected through the well-established system of cotton ball soaked with 6% glucose containing C. violaceum.

The data showed important properties of Burkina Faso C. violaceum strains, which are highly virulent against insecticide-resistant An. coluzzii, and reduce both mosquito blood feeding and fecundity propensities. However, additional studies as the sequencing of C. violaceum genome and the potential toxins secreted will provide useful information render it a potential candidate for the biological control strategies of malaria and other disease vectors.

News focuses on getting a handle on urban malaria in Uganda and Tanzania. Listen to a program on the disease burden of malaria in Africa.  Chad reports a high test positivity rate. Algeria is re-experiencing malaria after it was officially eliminated. Links for more details are found in each section.

Modelling and mapping the intra-urban spatial distribution of Plasmodium falciparum parasite rate using very-high-resolution satellite derived indicators

Stefanos Georganos, Oscar Brousse, Moritz Lennert, and others in International Journal of Health Geographics report on the rapid and often uncontrolled rural–urban migration in Sub-Saharan Africa is transforming urban landscapes expected to provide shelter for more than 50% of Africa’s population by 2030. Case studies include two Sub-Saharan African cities, Kampala and Dar es Salaam.

Openly accessible land-cover, land-use, population and OpenStreetMap data were employed to spatially model Plasmodium falciparum parasite rate standardized to the age group 2–10 years (PfPR2–10) in the two cities through the use of a Random Forest (RF) regressor. The RF models integrated physical and socio-economic information to predict PfPR2–10 across the urban landscape. Intra-urban population distribution maps were used to adjust the estimates according to the underlying population.

The results suggest that the spatial distribution of PfPR2–10 in both cities is diverse and highly variable across the urban fabric. Dense informal settlements exhibit a positive relationship with PfPR2–10 and hotspots of malaria prevalence were found near suitable vector breeding sites such as wetlands, marshes and riparian vegetation. In both cities, there is a clear separation of higher risk in informal settlements and lower risk in the more affluent neighborhoods. Additionally, areas associated with urban agriculture exhibit higher malaria prevalence values. This study demonstrates the importance of remote sensing as an epidemiological tool for mapping urban malaria variations at large spatial extents, and for promoting evidence-based policy making and control efforts.

Malaria: Africa’s nagging health burden

Listen to Episode Nine of Africa Science Focus is on malaria, which is one of the biggest killers on the continent. “Malaria is so common you can get it anywhere, anyhow, any time,” Jessica, a malaria sufferer in Liberia, tells the programme. This is because Africa’s mosquitoes are “supremely efficient vectors of malaria disease”, says the World Health Organization’s David Schellenberg.

Malaria: More than 500K cases reported in Chad, Deadliest disease in country

According to data from the National Committee for Epidemic Control (CTNLE), out of the 943,040 malaria tests conducted between 1 January and 13 September 2020, a total of 571,258 cases were confirmed (60.5 percent), with 1,280 deaths across the country. In addition close to 1,140,000 suspected cases based on clinical symptoms but who have not been tested. Among these suspected cases, 1,368 people have died. The most affected provinces are, among others, Logone oriental (with a total of 80,930 cases), Mandoul (82 258 cases), Moyen-Chari (60 207 cases), Tandjle (55 777 cases) and N’Djamena (53 976 cases).

Officials say the situation is slightly better than last year around the same period when 689,563 cases were confirmed and 1,323 died – a difference of 118,305 cases and 43 deaths. However, the situation has worsened compared to 2017 and 2018 when the number of confirmed cases were 524,148 and 534,781 (with 957 and 922 deaths) respectively.

Algeria faces new malaria cases one year after victory over deadly disease

Algeria Tuesday registered over 1,000 cases of malaria, one year after the World Health Organization (WHO) declared the country malaria-free. The cases, according to the health ministry, are imported cases and have been spotted in five governorates namely Tamanrasset (918), Adrar (96), Illizi (89), Ouargla (5) and Ghardaïa (2).

The ministry noted that every year, in September after first rains, the country often registers imported malaria cases, hailing from Sahel neighboring countries or Algerians who sojourned in those countries. The WHO in May 2019, declared Algeria malaria-free. The certification is awarded to countries after three straight years of zero home-born cases of malaria.

Mosquito populations vary across nations and can be spurred by change in land use and deforestation as seen in Madagascar. Urine and saliva have potential in diagnostics but have lower sensitivity than blood tests. Not all insects have similar genes, and mosquitoes evolved a different gene to handle body segmentation. The DHS Program has released recent Malaria Indicator Surveys for Ghana and Uganda, but indicators are below targets. The emerging roles for neutrophils in malaria will be discussed at a webinar. Finally cost-effectiveness issues around RDTs is noted. More information can be obtained via the hyperlinks.

Variation in Anopheles distribution and predictors of malaria infection risk across regions of Madagascar

Deforestation and land use change is widespread in Madagascar, altering local ecosystems and creating opportunities for disease vectors, such as the Anopheles mosquito, to proliferate and more easily reach vulnerable, rural populations. Knowledge of risk factors associated with malaria infections is growing globally, but these associations remain understudied across Madagascar’s diverse ecosystems experiencing rapid environmental change. This study aims to uncover socioeconomic, demographic, and ecological risk factors for malaria infection across regions through analysis of a large, cross-sectional dataset.

The presence of aquatic agriculture (both within and surrounding communities) is the strongest predictive factor of habitats containing Anopheles larvae across all regions. Ecological and socioeconomic risk factors for malaria infection vary dramatically across study regions and range in their complexity. Risk factors for malaria transmission differ dramatically across regions of Madagascar. These results may help stratifying current malaria control efforts in Madagascar beyond the scope of existing interventions.

Evaluating the potential of using urine and saliva specimens for malaria diagnosis in suspected patients in Ghana

This study aimed at detecting PfHRP2 and pLDH malaria antigens in urine and salivary specimens of suspected malaria patients using RDT kits, and identifying factors influencing the detection of these antigens. Malaria rapid test kit (SD Bioline RDT kit) was used to detect malaria antigens, PfHRP2 and pLDH, in blood, urine and saliva samples received from patients suspected of malaria. Subsequently, malaria parasitaemia was determined.

A total of 706 suspected malaria patients provided all three specimens. Prevalence of malaria by microscopy and RDT was 44.2% and 53.9%, respectively. Compared to blood, the sensitivities of urine and saliva were 35.2% and 57.0% respectively. Haemoglobin concentration?<?9.9 g/dL, body temperature?>?38.7 °C and occult blood influenced the detection of malaria antigens in both urine and saliva. Furthermore, the antigens were not detected in urine and saliva when parasitaemia was?<?60,000 parasites/µL and?<?40,000 parasites/µL, respectively.

Saliva, with or without blood contamination, was found to be more efficient that urine samples. Therefore these non-blood specimens have the potential to be used as non-invasive samples for malaria diagnosis. However, this approach is useful in severe to moderate anaemia, hyperthermia, parasitaemia?>?60,000 parasites/µL and samples contaminated with blood.

Mosquitos lost an essential gene for body segmentation with no ill effects

University of Maryland entomologists discovered that a gene critical for survival in other insects is missing in mosquitoes—the gene responsible for properly arranging the insects’ segmented bodies. The researchers also found that a related gene evolved to take over the missing gene’s job. Although laboratory studies have shown that similar genes can be engineered to substitute for one another, this is the first time that scientists identified a gene that naturally evolved to perform the same critical function as a related gene long after the two genes diverged down different evolutionary paths.

The work emphasizes the importance of caution in genetic studies that use model animals to make conclusions across different species. It also points to a new potential avenue for research into highly targeted mosquito control strategies. The research study was published in the September 30, 2020, issue of the journal Communications Biology. “Every single arthropod has a segmented body plan. And you would think it develops the same way in all of them. But what we found is that it doesn’t,” said Alys Jarvela. “That means different genes probably regulate male fertility in mosquitoes, and they might be unique to the mosquito, which could potentially provide a powerful avenue for controlling mosquitoes without harming other insects such as butterflies and bees,” Jarvela said.

Two New Malaria Indicator Surveys Available

Ghana 2019 MIS/DHS Infographic. Malaria prevalence going down from 27% in 2014 to 14% in 2019. Still below target in terms of ITN coverage of and in households.

Uganda 2018-19 MIS/DHS Infographic.  Wide regional variation in malaria prevalence from 1-5% in the southwest to 34% in the northeast. ITN use by children and pregnant women below 2/3rds, while only 2/5 pregnant women got 3 doses of IPT.

Emerging Roles for Neutrophils in Malaria

Aubrey Cunnington and an interdisciplinary translational research group studying host-pathogen interactions in severe infections, focussing on malaria in particular. See for example,  “A More Granular View of Neutrophils in Malaria”

Neutrophils are abundant innate immune cells with crucial roles in immunity and vascular inflammation. Recent evidence indicates that neutrophils have a dual role in malaria, contributing to both pathogenesis and control of Plasmodium. We discuss emerging mechanisms behind these opposing functions and identify key outstanding questions.

Cost-effectiveness analysis of malaria rapid diagnostic test in the elimination setting

As more and more countries approaching the goal of malaria elimination, malaria rapid diagnostic tests (RDT) was recomended to be a diagnostic strategy to achieve and maintain the statute of malaria free, as it’s less requirements on equipment and expertise than microscopic examination. But there are very few economic evaluations to confirm whether RDT was cost-effective in the setting of malaria elimination. This research aimed to offer evidence for helping decision making on malaria diagnosis strategy.

The results showed that RDT strategy was the most effective (245 cases) but also the most costly (United States Dollar [USD] 4.47 million) compared to using microscopy alone (238 cases, USD 3.63 million), and RDT followed by microscopy (221 cases, USD 2.75 million). There was no strategy dominated. One-way sensitivity analysis reflected that the result was sensitive to the change in labor cost and two-way sensitivity analysis indicated that the result was not sensitive to the proportion of falciparum malaria. The result of Monte Carlo simulation showed that RDT strategy had higher effects and higher cost than other strategies with a high probability. Compared to microscopy and RDT followed by microscopy, RDT strategy had higher effects and higher cost in the setting of malaria elimination.

A variety of malaria and related issues have arisen over the past two days. A media coalition for malaria elimination formed in Ghana. A Nigerian NGO stresses the importance of addressing malaria on Nigeria’s 60th Independence Day (October 1). An innovative technology foundation is supporting various malaria and NTD treatment and diagnostic research efforts. Click on links below to read the details.

Media Coalition for malaria control and elimination launched

A Media Coalition comprising of selected journalists and editors, has been launched in Ghana under the umbrella of the “Zero Malaria Starts with Me” campaign to eliminate malaria by 2030. The Coalition, which aimed to enhance the quality and quantity of malaria coverage, and support broader advocacy efforts, was launched at a workshop in Accra organized by the National Malaria Control Programme (NMCP), in collaboration with the African Media and Malaria Research Network and Speak Up Africa, an advocacy and communication Organisation based in Senegal.

The workshop brought together media personnel from across the regions, who nominated their Regional Executives, with two National Co-Chairpersons coming from Greater Accra. The Members of the Coalition, made a firm declaration of their commitment towards the elimination of malaria in Ghana by the year 2030, by championing the fight, taking responsibility for their roles through proactive, regular, accurate, and high-quality media output of news on malaria.

Chinwe Chibuike Foundation Set To Flag-off Full Scale Malaria Eradication Program On Independence Day

A Nigeria indigenous and international non-governmental organization, envisioned to create a conducive environment towards the accessibility of healthcare facilities and improved educational opportunities, has joined the fight against the bizzare challenges of Malaria. The renowned Nigeria-USA humanitarian organization, Chinwe Chibuike Foundation is collaborating with other organizations to flagoff a full scale malaria eradication exercise tagged “Nigeria at 60 Malaria Eradication Project”, on the 1st of October 2020.

According to the founder and President of Chinwe Chibuike Foundation, Ms Gloria Chibuike, during an interview session with Pulse TV few days ago, she noted the forthcoming Nigeria At 60 Malaria Eradication Program will be different and of more impact, especially with the full scale approach and introduction a new Malaria repellant Band.

While emphasizing on the extensive features of the project, Ms Gloria described Malaria as one of the biggest problems in Africa at the moment, considering the increased number of recorded deaths and infection. She narrated that the discovery of the new malaria repellent band was timely and off-course very efficient, especially with testimonies from few persons who have already tried the brand.

Drugs and Diagnostics: Malaria and NTDs

The Global Health Innovative Technology (GHIT) Fund announced today a total of 1.37 billion yen (US$13 million*) to invest in seven partnerships to develop new lifesaving drugs and diagnostics for malaria, Buruli ulcer, Chagas disease, leishmaniasis, schistosomiasis, and soil-transmitted helminths (STH). This includes three newly funded projects and four that will receive continued funding. The RBM Partnership is planning on how to monitor and provide technical support for ITN programs. Click the links within each section to read details.

As of September 29, GHIT’s portfolio includes 50 ongoing projects: 26 discovery projects, 16 preclinical projects and eight clinical trials (Appendix 3). The total amount of investments since 2013 is 22.3 billion yen (US$211 million).

Support the Improvement of Operational Efficiency of ITN Campaigns

The Alliance for Malaria Prevention (AMP) is a workstream within the RBM Partnership to End Malaria. With malaria indicators stagnating and intense pressure to improve access and use of effective ITNs, WHO has renewed focus on stratifying vector control strategies in countries. Along with the introduction of new, more expensive ITNs, countries are now challenged to determine where they should deploy different ITN types to manage insecticide resistance within limited funding envelopes, as well as to identify more efficient ways to implement mass ITN distribution.

Countries that have accessed AMP technical assistance have significantly improved their capacity to modify and update strategies and tools to increase ITN access, use and accountability. They have also continued to identify further gaps and look for effective ways to address them. Now AMP planning to support update and finalization of ITN tracking tool, aligned with priorities across major partners (GF, PMI, RBM).

Today’s selection of abstracts and news looks at the role of the media in supporting malaria programs, mass treatment to prevent Imported malaria, problems managing malaria in pregnancy services, malaria research in Mali and health systems strengthening to support malaria control in Guinea. Follow links to read mor details.

GHS calls for media support to eradicate malaria

The media has a role in supporting malaria programs

The Ghana Health Service (GHS) has called on journalists to support the Service to deliver integrated health package through accurate messages towards malaria eradication in the country.“Also, we need your support to set malaria as a national development agenda. This will drive advocacy for political will, increase partnership, availability and accessibility of effective tool for prevention, diagnoses and treatment of malaria in all the vulnerable populations.”

Dr Anthony Adofo Ofosu, the Deputy Director General, GHS, said this at the launch of “Zero malaria starts with me” campaign in Accra.  The launch coincided with a sensitisation programme by the African Media and Malaria Research Network (AMMRN), the National Malaria Control Programme and the Speak Up African Organisation. The Deputy Director General said “It is the belief of the GHS that with effective engagement…we will be able to eradicate malaria from the country in the near future.”

Mass radical treatment of a group of foreign workers to mitigate the risk of re-establishment of malaria in Sri Lanka

Following malaria elimination, Sri Lanka was free from indigenous transmission for six consecutive years, until the first introduced case was reported in December 2018. The source of transmission (index case) was a member of a group of 32 migrant workers from India and the location of transmission was their residence reporting a high prevalence of the primary vector for malaria. Despite extensive vector control the situation was highly susceptible to onward transmission if another of the group developed malaria. Therefore, Mass Radical Treatment (MRT) of the group of workers for Plasmodium vivax malaria was undertaken to mitigate this risk.

The workers were screened for malaria by microscopy and RDT, their haemoglobin level assessed, and tested for Glucose 6 phosphate dehydrogenase deficiency (G6PD) using the Care Start RDT and Brewers test prior to treatment with chloroquine (CQ) 25 mg/kg body weight (over three days) and primaquine (PQ, based on G6PD test results) (0.25 mg/kg/day bodyweight for 14 days) following informed consent. All were monitored for adverse events. None of the foreign workers were parasitaemic at baseline screening.

Mass treatment may be an option in prevention of reintroduction settings for groups of migrants who are likely to be carrying latent malaria infections, and resident in areas of high receptivity. However, in the case of Plasmodium vivax and Plasmodium ovale, a more reliable and affordable point-of-care test for G6PD activity would be required. Most countries which are eliminating malaria now are in the tropical zone and face considerable and similar risks of malaria re-introduction due to massive labour migration between them and neighbouring countries. Regional elimination of malaria should be the focus of global strategy if malaria elimination from countries is to be worthwhile and sustainable.

Managing intermittent preventive treatment of malaria in pregnancy challenges: an ethnographic study of two Ghanaian administrative regions

Malaria in pregnancy (MiP) is an important public health problem across sub-Saharan Africa. The package of measures for its control in Ghana in the last 20 years include regular use of long-lasting insecticide-treated bed nets (LLINs), directly-observed administration (DOT) of intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) and prompt and effective case management of MiP. Unfortunately, Ghana like other sub-Saharan African countries did not achieve the reset Abuja targets of 100% of pregnant women having access to IPTp and 100% using LLINs by 2015.

This ethnographic study explored how healthcare managers dealt with existing MiP policy implementation challenges and the consequences on IPTp-SP uptake and access to maternal healthcare. Healthcare managers addressed frequent stock-outs of malaria programme drugs and supplies from the National Malaria Control Programme and delayed reimbursement from the NHIS, by instituting co-payment, rationing and prescribing drugs for women to buy from private pharmacies.

Some clients did not receive the recommended 5?+?doses of SP, others did not obtain LLINs early and some did not obtain treatment for MiP. Healthcare providers felt frustrated whenever they could not provide comprehensive care to women who could not afford comprehensive maternal and MiP care. For Ghana to achieve her goal of controlling MiP, the Ministry of Health and other supporting institutions need to ensure prompt reimbursement of funds, regular supply of programme drugs and medical supplies to public, faith-based and private health facilities.

Malaria prevention program continuation in Guinea

CRS Guinea is the Principal Recipient (PR) in Malaria prevention program continuation grant by the Global Fund for the new cycle of funding (NFM) (January 2021-December 2023). Community health is a top priority of the Ministry of Health as a primary strategy to increase accessibility and coverage to basic health services. Under the new Global Fund grant, the community health component will be expanded to six districts, in addition to two pilot districts, Kindia and Telimele. CRS will also support coordination with other donors, including World Bank, UNICEF, Gavi, European Union and the Guinea Ministry of Health to implement the national community health strategy in 12 health districts supported by Global Fund malaria project.

The United States and Mali Celebrate 60 Years of Friendship and Partnership

Thirty years ago, our National Institutes of Health created a Malaria Research and Training Center, which is now a component of the International Center for Excellence in Research in Mali. Until today, it serves as a reference center with over 700 Malian scientists and support staff who work on malaria and other infectious diseases. Together, we have dropped malaria prevalence rates in Mali by an astounding 60 percent since 2012.

Differentiating malaria parasite species is something science can do today, but in the 1800s the debate was over what actually caused the disease.  This ability to test and diagnose gives us an important surveillance tool, the 3Ts. News from Ghana is that malaria deaths are reducing, and Guatemala is focusing on elimination. Read more at the links in each section.

Wyss Researchers Develop Malaria Diagnostic Procedure Capable of Differentiating Malaria Species

Researchers at Harvard’s Wyss Institute have developed a new malaria diagnostic test that efficiently detects and can distinguish between species of malaria parasites,
the new procedure significantly improves upon current diagnostic methods, which fail to differentiate between types of malaria. Procedures that only identify Plasmodium falciparum can lead to severe consequences for patients, since other types of malaria are resilient to therapies designed to treat Plasmodium falciparum because they enter a dormant stage in the human liver.

These genes help explain how malaria parasites survive treatment with common drug.

The essential malaria drug artemisinin acts like a “ticking time bomb” in parasite cells—but in the half a century since the drug was introduced, malaria-causing parasites have slowly grown less and less susceptible to the treatment, threatening attempts at global control over the disease.

In a paper published September 23 in Nature Communications, Whitehead Institute Member Sebastian Lourido and colleagues use genome screening techniques in the related parasite Toxoplasma gondii (T. gondii) to identify genes that affect the parasites’ susceptibility to artemisinin. Two genes stood out in the screen: one that makes the drug more lethal, and another that helps the parasite survive the treatment…

Test, Treat, and Track: Strengthening Malaria Response Capabilities in Sierra Leone

A public-private partnership in Sierra Leone aimed to build capacity for testing, treating, and tracking malaria. The post notes the “public-private partnership in Sierra Leone was a collaboration between USAID’s Human Resources for Health in 2030 (HRH2030) program; the U.S. President’s Malaria Initiative (PMI), the Global Fund to Fight AIDS, Tuberculosis and Malaria; the Pharmacy Consultancy of Sierra Leone; and the Sierra Leone National Malaria Control Program”.

NMCP partnered with pharmacies to strengthen their malaria case management capabilities. Anitta and her colleague Brenda Stafford, a trained pharmacist and Procurement and Supply Management officer, led the initiative, going pharmacy-to-pharmacy to train staff on the NMCP’s “Three T” approach: Test, Treat, and Track.

To address the first T, private pharmacies were given free malaria rapid diagnostic tests. According to 2016 data, only half of children under-five with fever received appropriate malaria testing. For the second T, the pharmacists were trained on malaria prevention, treating patients with uncomplicated malaria, and referring patients with severe malaria to health facilities. As for the last T, tracking malaria test results is key in forecasting the spread of disease. NMCP provided pharmacies with two forms that track results: a registry form to track patient information and a summary form which aggregates that into monthly data reports

Miasma War over cause of malaria was heated

Nicole Layton of the Chowan Herald reported that in the 1850s, two North Carolina doctors had a heated and protracted battle over the cause of malaria in the state. This Miasma War is so famous. So what the heck is Miasma? Those fans of Charles Dickens can tell you that at one point miasmas were thought to be the main vector for disease transmission.

During Dickens’ time in London the air was very foul and rather visible because of wood and coal and it smelled bad due to the lack of indoor plumbing. It was thought that this foul air was the cause of disease. Because our part of North Carolina had a lot of rotting vegetation and swamps there was certainly foul air about and very noticeable illness. So the general thought was that malaria was a result of this bad air.

Escuintla, Guatemala: Clinton Health Access Initiative (CHAI)

CHAI’s Guatemala Malaria Team is supporting the Ministry of Health’s National Malaria Program by providing technical assistance and supporting programmatic planning, execution, monitoring and evaluation of effective interventions in the department of Escuintla in southern Guatemala. Over the past five years, CHAI has engaged in the country and helped them make meaningful steps towards orienting their national strategic plans and systems towards the historical goal of malaria elimination.

CHAI’s Guatemala team works in close coordination with the Ministry of Health and other international partners to design, plan, execute and evaluate the impact of the country´s elimination-focused interventions in Escuintla.

Ghana: Malaria deaths in children under five reduce

Ghana has recorded a reduction in malaria deaths in children under five by 83 per cent over the last eight years, the National Malaria Control Programme (NMCP) has said. The rate of malaria-related deaths reduced from 0.6 per cent in 2012 to 0.1 per cent in 2019, showing significant inroads in malaria-related deaths among children. Malaria-related deaths of all ages also reduced by 2,799 in 2012 to 333 by end of 2019, representing an 88 per cent reduction.