Tropical Health Matters

Anthony AHUMIBE is a staff member of Nigeria CDC and presently a doctoral student at the Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan. Herein he examines the challenges posed by Lassa Fever to the West African region.

Following the West Africa Ebola epidemic of 2014, the global community has been preoccupied with Lassa fever, a zoonotic viral infection that has caused sickness and death in some communities in Nigeria, Liberia, Sierra Leone, and Guinea. Familiar challenges like absence of vaccine and point of care diagnostics are being handled through investments in research and development. There are, however, some imperceptible yet weighty challenges along the path of Lassa fever control.

The recent finding by Happi and colleagues shows that several species of household rodents, nonspecific to the familiar multimammate rats and other peri-urban small animals carry the Lassa virus and demonstrate that the virus is adapting. Conversely the economic turn of events in the endemic countries indicates that more people are moving into poverty and are unable to make proper hygiene choices. Furthermore, the expansion of city slums, and poor structured housing increases the opportunity for human contact with these rodents, thereby increasing rodents to human virus transmission.

The table derives from weekly reports published by NCDC. Nigeria Lassa fever data summary for Epi week 15, 2024 is compared with Epi Week 15 cumulative data in 2023 and 2024 (Courtesy: Nigeria CDC Situation report).

Related to the issue of homestead hygiene is the ineffective management of hospital waste in most of these communities. Many cases of Lassa fever slip through the cracks as malaria fever in health centres with limited capacity for molecular diagnosis.  After treatment, body fluid-stained dressings and disposables as well as serum and other body fluids are disposed as waste. The ineffectual medical waste management, so unsupervised, promotes fomite-rodent transmission and genetic spill-over to other species of household animals.

Citizens in the endemic countries share the same burden of poor health infrastructure and limited access to healthcare. For instance, only about 3% of adults aged 15-49 years have a form of health insurance. The high out-of-pocket expenditure required has caused increased hesitance in visiting hospital. As an alternative, many persons become victims of charlatans while genuine traditional healers who approach medical care blindly and without protective equipment become targets of infection and sources of transmission.

The photo (by author) shows the traditional sun drying of grated cassava for fufu meal. This exposure increases potential for Lassa fever transmission through contamination with rodent excreta.

The large trust deficit between the citizens and the political leaders owing to the several years of perceived economic and social mismanagement is also a great source of concern. Trust in the system by the people has been affirmed as necessary in advancing the cause of public health. Marcia McNutt and Michael Crow wrote in their op-ed, published in Issues in Science and Technology magazine that scientists and elected leaders need to earn citizens’ trust to win the war against misinformation and disinformation. Hesitancy in uptake of available countermeasures, appropriate risk perception and required behavioural change, seem imperiled in these communities due to the lack of trust in government and government institutions.

Finally, it is often assumed that every new infection cycle is initiated by human contact with rodent or rodent fluid. This does not consider however that the reinfection cycle could have started from a lab leak. Pathogen escape pathways are preponderant with many vials of remnant serum held unaccounted for in many public and private care institutions, some in community hospitals. This can only change if these countries develop a national system for accountability and repository of high-consequence pathogens.

In the past week, news has featured challenges to malaria elimination around the globe. Starting in Papua New Guinea which accounted for accounted for 86% of all cases in the Western Pacific Region in 2020. While there are 39% fewer cases in the region since 2000, there was an increase of 300,000 cases between 2019 and 2020. It is mainly in the six countries of the Greater Mekong subregion where progress has been steady.

Moving east to the Brazilian Amazon, one finds wildcat gold mining operations are not only destroying Native American ecosystems but are carving huge holes in the earth which are perfect breeding conditions for mosquitoes. This means that malaria cases among the Yanomami indigenous people living in the Brazilian Amazon have increased by more than 12 times since 2014.

Also within South America, one finds that although Paraguay was certified by the World Health Organization (WHO) as free of local transmission of malaria in 2018, experts are warning that travelers entering the country from areas with malaria transmission could easily reintroduce the disease. Hence vigilance is urged.

Crossing next to sub-Saharan Africa, one reads of studies showing an increasing link between malaria and agriculture across the region. As population expands in the region, more food, water and agricultural commodities are required. Irrigation and deforestation to clear land for agriculture increase the risk of childhood malaria in sub-Saharan Africa. The experts recommend that African ministries of agriculture, health, and environment need to collaborate on safer development policies and practices, not only to curb malaria, but the devastating effects of climate change.

Finally continuing back to Asia, one finds what might be termed an epidemiological conflict between Nepal, which is nearing malaria elimination for 2025, and its southern neighbor India, which is a source of imported malaria. Although the number of indigenous cases is nearing zero, health authorities fear that imported cases of of malaria from India are so high that local transmission could be reignited.

Malaria is clearly a global health problem. Collaboration and coordination across continents is needed to eliminate the scourge.

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.

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.

Today’s stories cover three continents including Surveillance for imported malaria in Sri Lanka, community perceptions in Colombia and Annual Fluctuations in Malaria Transmission Intensity in 5 sub-Saharan countries. In addition there is an overview of microscopy standards and an Integrated Macroeconomic Epidemiological Demographic Model to aid in planning malaria elimination. We also see how COVID-19 is disturbing Seasonal Malaria Chemoprevention activities in Burkina Faso. Read more by following the links in the sections below.

Will More of the Same Achieve Malaria Elimination?

… Results from an Integrated Macroeconomic Epidemiological Demographic Model. Historic levels of funding have reduced the global burden of malaria in recent years. Questions remain, however, as to whether scaling up interventions, in parallel with economic growth, has made malaria elimination more likely today than previously. The consequences of “trying but failing” to eliminate malaria are also uncertain. Reduced malaria exposure decreases the acquisition of semi-immunity during childhood, a necessary phase of the immunological transition that occurs on the pathway to malaria elimination. During this transitional period, the risk of malaria resurgence increases as proportionately more individuals across all age-groups are less able to manage infections by immune response alone. We developed a robust model that integrates the effects of malaria transmission, demography, and macroeconomics in the context of Plasmodium falciparum malaria within a hyperendemic environment.

The authors analyzed the potential for existing interventions, alongside economic development, to achieve malaria elimination. Simulation results indicate that a 2% increase in future economic growth will increase the US$5.1 billion cumulative economic burden of malaria in Ghana to US$7.2 billion, although increasing regional insecticide-treated net coverage rates by 25% will lower malaria reproduction numbers by just 9%, reduce population-wide morbidity by ?0.1%, and reduce prevalence from 54% to 46% by 2034. As scaling up current malaria control tools, combined with economic growth, will be insufficient to interrupt malaria transmission in Ghana, high levels of malaria control should be maintained and investment in research and development should be increased to maintain the gains of the past decade and to minimize the risk of resurgence, as transmission drops. © The American Society of Tropical Medicine and Hygiene [open-access]

Microscopy standards to harmonise methods for malaria clinical research studies

Research Malaria Microscopy Standards (ReMMS) applicable to malaria clinical research studies have been published in Malaria Journal. The paper describes the rationale for proposed standards to prepare, stain and examine blood films for malaria parasites. The standards complement the methods manual(link is external) previously published by the World Health Organization and UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR). The standards aim to promote consistency and comparability of data from microscopy performed for malaria research and hence to strengthen evidence for improvements in malaria prevention, diagnostics and treatment.

Microscopy is important in both malaria diagnosis and research. It is used to differentiate between Plasmodium species and stages and to estimate parasite density in the blood – an important determinant of the severity of disease. It is also used to monitor the effectiveness of drugs based on the rate at which parasites recrudesce or are cleared from the blood.

While rapid diagnostic tests have replaced microscopy in some contexts, microscopy remains an essential tool to support clinical diagnosis and research. The standardisation of methods allows direct comparisons from studies conducted across different points in time and location. This facilitates individual participant data meta-analyses, recognised as the gold standard approach to generate evidence for improvements in interventions and hence patient outcomes.

Estimating Annual Fluctuations in Malaria Transmission Intensity and in the Use of Malaria Control Interventions in Five Sub-Saharan African Countries

RTS,S/AS01E malaria vaccine safety, effectiveness, and impact will be assessed in pre- and post-vaccine introduction studies, comparing the occurrence of malaria cases and adverse events in vaccinated versus unvaccinated children. Because those comparisons may be confounded by potential year-to-year fluctuations in malaria transmission intensity and malaria control intervention usage, the latter should be carefully monitored to adequately adjust the analyses. This observational cross-sectional study is assessing Plasmodium falciparum parasite prevalence (PfPR) and malaria control intervention usage over nine annual surveys performed at peak parasite transmission. Plasmodium falciparum parasite prevalence was measured by microscopy and nucleic acid amplification test (quantitative PCR) in parallel in all participants, and defined as the proportion of infected participants among participants tested. Results of surveys 1 (S1) and 2 (S2), conducted in five sub-Saharan African countries, including some participating in the Malaria Vaccine Implementation Programme (MVIP), are reported herein; 4,208 and 4,199 children were, respectively, included in the analyses.

Plasmodium falciparum parasite prevalence estimated using microscopy varied between study sites in both surveys, with the lowest prevalence in Senegalese sites and the highest in Burkina Faso. In sites located in the MVIP areas (Kintampo and Kombewa), PfPR in children aged 6 months to 4 years ranged from 24.8% to 27.3%, depending on the study site and the survey. Overall, 89.5% and 86.4% of children used a bednet in S1 and S2, of whom 68.7% and 77.9% used impregnated bednets. No major difference was observed between the two surveys in terms of PfPR or use of malaria control interventions. © The American Society of Tropical Medicine and Hygiene [open-access]

Community perception of malaria in a vulnerable municipality in the Colombian Pacific

Malaria primarily affects populations living in poor socioeconomic conditions, with limited access to basic services, deteriorating environmental conditions, and barriers to accessing health services. Control programmes are designed without participation from the communities involved, ignoring local knowledge and sociopolitical and cultural dynamics surrounding their main health problems, which implies imposing decontextualized control measures that reduce coverage and the impact of interventions. The objective of this study was to determine the community perception of malaria in the municipality of Olaya Herrera in the Colombian Pacific.

A 41-question survey on knowledge, attitudes, and practices (KAP) related to malaria, the perception of actions by the Department of Health, and access to the health services network was conducted. In spite of the knowledge about malaria and the efforts of the Department of Health to prevent it, the community actions do not seem to be consistent with this knowledge, as the number of cases of malaria is still high in the area.

Use of a Plasmodium vivax genetic barcode for genomic surveillance and parasite tracking in Sri Lanka

Sri Lanka was certified as a malaria-free nation in 2016; however, imported malaria cases continue to be reported. Evidence-based information on the genetic structure/diversity of the parasite populations is useful to understand the population history, assess the trends in transmission patterns, as well as to predict threatening phenotypes that may be introduced and spread in parasite populations disrupting elimination programmes. This study used a previously developed Plasmodium vivax single nucleotide polymorphism (SNP) barcode to evaluate the population dynamics of P. vivax parasite isolates from Sri Lanka and to assess the ability of the SNP barcode for tracking the parasites to its origin.

A total of 51 P. vivax samples collected during 2005–2011, mainly from three provinces of the country, were genotyped for 40 previously identified P. vivax SNPs using a high-resolution melting (HRM), single-nucleotide barcode method. The proportion of multi-clone infections was significantly higher in isolates collected during an infection outbreak in year 2007. Plasmodium vivax parasite isolates collected during a disease outbreak in year 2007 were more genetically diverse compared to those collected from other years. In-silico analysis using the 40 SNP barcode is a useful tool to track the origin of an isolate of uncertain origin, especially to differentiate indigenous from imported cases. However, an extended barcode with more SNPs may be needed to distinguish highly clonal populations within the country.

Coronavirus rumours and regulations mar Burkina Faso’s malaria fight

By Sam Mednick, Thomson Reuters Foundation: MOAGA, Burkina Faso – Health worker Estelle Sanon would hold the 18-month-old and administer the SMC dose herself, but because of coronavirus she has to keep a distance from her patients. “If I am standing and watching the mother do it, it’s as if I’m not doing my work,” said Sanon, a community health volunteer assisting in a seasonal campaign to protect children in the West African country from the deadly mosquito-borne disease.

Burkina Faso is one of the 10 worst malaria-affected nations in the world, accounting for 3% of the estimated 405,000 malaria deaths globally in 2018, according to the World Health Organization (WHO). More than two-thirds of victims are children under five. Now there are fears malaria cases could rise in Burkina Faso as restrictions due to coronavirus slow down a mass treatment campaign and rumours over the virus causing parents to hide their children, according to health workers and aid officials.

“COVID-19 has the potential to worsen Burkina Faso’s malaria burden,” said Donald Brooks, head of the U.S. aid group Initiative: Eau, who has worked on several public health campaigns in the country.  “If preventative campaigns can’t be thoroughly carried out and if people are too scared to come to health centres … it could certainly increase the number of severe cases and the risk of poor outcomes.”

During peak malaria season, from July to November, community health workers deploy across Burkina Faso to treat children with seasonal malaria chemoprevention (SMC). This is the second year the campaign will cover the whole country with more than 50,000 volunteers going door-to-door, said Gauthier Tougri, coordinator for the country’s anti-malaria programme. Logistics were already challenging. Violence linked to jihadists and local militias has forced more than one million people to flee their homes, shuttered health clinics and made large swathes of land inaccessible. Now the coronavirus has made the task even harder, health workers said.

People in Cape Verde evolved better malaria resistance in 550 years

Yes, we are still evolving. And one of the strongest examples of recent evolution in people has been found on the Cape Verde islands in the Atlantic, where a gene variant conferring a form of malaria resistance has become more common.

Portuguese voyagers settled the uninhabited islands in 1462, bringing slaves from Africa with them. Most of the archipelago’s half a million inhabitants are descended from these peoples. Most people of West African origin have a variant in a gene called DARC that protects.

Deadly malaria and cholera outbreaks grow amongst refugees as COVID pandemic strains health systems.

Apart from the strain on health facilities during the pandemic, in some countries such as Somalia, Kenya and Sierra Leone, we are seeing that a fear of exposure to COVID-19 has prevented parents from taking their children to hospital, delaying diagnosis and treatment of malaria and increasing preventable deaths. COVID restrictions in some countries have also meant pregnant women have missed antimalarial drugs. Untreated malaria in pregnant women can increase the risk of anaemia, premature births, low birth weight and infant death. According to the World Health Organization (WHO), 80% of programs designed to fight HIV, tuberculosis and malaria have been disrupted due to the pandemic and 46% of 68 countries report experiencing disruptions in the treatment and diagnosis of malaria.

Controversy exists about what historical event should be observed in the USA on 12th October. Ernest Faust explained many years ago that, “there is neither direct nor indirect evidence that the malaria parasites existed on this continent prior to the advent of the European conquerors,” while at the same time in the 16th through 18th Centuries, malaria was common in England, Spain, France, Portugal and other European nations that arrived in the “New World.” Initially, with the first voyage of Columbus the European explorers and settlers brought the disease, primarily Plasmodium vivax, while the slave trade brought P. falciparum.

National Geographic in its May 2007 issue provided the story “Jamestown, The Real Story.” This article reported that, “Colonists carried the plasmodium parasite to Virginia in their blood. Mosquitoes along the Chesapeake were ‘infected’ by the settlers and spread the parasite to other humans.” Thus malaria became one of many imported diseases that decimated the indigenous population. The spread of P. vivax in Jamestown was not surprising since the settlement was “located on marshy ground where mosquitoes flourished during the summer.”

Recent research has shown that the “Analysis of genetic material extracted showed that the American P. falciparum parasite is a close cousin of its African counterpart.” This research has documented two genetic groups in Latin America, related to two distinct slave routes run by the Spanish empire in the North, West Indies, Mexico and Colombia and the Portuguese empire to Brazil. Indigenous and remote rural populations of Bolivia, Colombia, Ecuador, Peru, Venezuela and Brazil remain at risk today.

In the South American continent the  native American population might have brought Melanesian strains of P. vivax before the Europeans arrived, but colonizers brought new strains from both Europe and Africa, as well as P. falciparum. Clearly, human migration has played an important role in malaria parasite dissemination through the Americas.

But back to the North American Continent where the USA is observing the historical implications of 12th October, Mark Blackmore reminds us that, “Anthropological and archeological data provide no indication of mosquito-borne diseases among the indigenous people of North America prior to contact with Europeans and Africans beginning in the fifteenth century” (Wing Beats Volume 25 Winter 2015). The spread of malaria by European colonizers is certainly not something to celebrate today.

Below we highlight some of the news we have shared on our Facebook Tropical Health Group page during the past week.

Polio Persists

If all it took to eradicate a disease was a well proven drug, vaccine or technology, we would not be still reporting on polio, measles and guinea worm, to name a few. In the past week Afghanistan reported 2 wild poliovirus type 1 (WPV1) cases, and Pakistan had 3 WPV1 cases. Circulating vaccine-derived poliovirus type 2 (cVDPV2) was reported in Nigeria (1), DRC (4) and Ethiopia (3) from healthy community contacts.

Continued Ebola Challenges

In the seven days from Saturday to Friday (June 28) there were 71 newly confirmed Ebola Cases and 56 deaths reported by the Democratic Republic of Congo’s Ministry of Health. As Ebola cases continue to pile up in the Democratic Republic of the Congo (DRC), with 12 more confirmed Thursday and 7 more Friday, a USAID official said four major donors have jump-started a new strategic plan for coordinating response efforts. To underscore the heavy toll the outbreak has caused, among its 2,284 cases, as noted on the World Health Organization Ebola dashboard today, are 125 infected healthcare workers, including 2 new ones, DRC officials said.

Pacific Standard explained the differences in Ebola outbreaks between DRC today and the West Africa outbreak of 2014-16. On the positive side are new drugs used in organized trials for the current outbreak. The most important factor is safe, effective vaccine that has been tested in 2014-16, but is now a standard intervention in the DRC. While both Liberia and Sierra Leone had health systems and political weaknesses as post-conflict countries, DRC’s North Kivu and Ituri provinces are currently a war zone, effectively so for the past generation. Ebola treatment centers and response teams are being attacked. There are even cultural complications, a refusal to believe that Ebola exists. So even with widespread availability of improved technologies, teams may not be able to reach those in need.

To further complicate matters in the DRC, Doctors Without Borders (MSF) “highlighted ‘unprecedented’ multiple crises in the outbreak region in northeastern DRC. Ebola is coursing through a region that is also seeing the forced migration of thousands of people fleeing regional violence and is dealing with another epidemic. Moussa Ousman, MSF head of mission in the DRC, said, ‘This time we are seeing not only mass displacement due to violence but also a rapidly spreading measles outbreak and an Ebola epidemic that shows no signs of slowing down, all at the same time.’”

NIPAH and Bats

Like Ebola, NIPAH is zoonotic, and also involves bats, but the viruses differ. CDC explains that, “Nipah virus (NiV) is a member of the family Paramyxoviridae, genus Henipavirus. NiV was initially isolated and identified in 1999 during an outbreak of encephalitis and respiratory illness among pig farmers and people with close contact with pigs in Malaysia and Singapore. Its name originated from Sungai Nipah, a village in the Malaysian Peninsula where pig farmers became ill with encephalitis.

A recent human outbreak in southern India has been followed up with a study of local bats. In a report shared by ProMED, out of 36 Pteropus species bats tested for Nipah, 12 (33%) were found to be positive for anti-Nipah bat IgG antibodies. Unlike Ebola there are currently no experimental drugs or vaccines.

Climate Change and Dengue

Climate change is expected to heighten the threat of many neglected tropical diseases, especially arboviral infections. For example, the New York Times reports that increases in the geographical spread of dengue fever. Annually “there are 100 million cases of dengue infections severe enough to cause symptoms, which may include fever, debilitating joint pain and internal bleeding,” and an estimated 10,000 deaths. Dengue is transmitted by Aedes mosquitoes that also spread Zika and chikungunya. A study, published Monday in the journal Nature Microbiology, found that in a warming world there is a strong likelihood for significant expansion of dengue in the southeastern United States, coastal areas of China and Japan, as well as to inland regions of Australia. “Globally, the study estimated that more than two billion additional people could be at risk for dengue in 2080 compared with 2015 under a warming scenario.”

Schistosomiasis – MDA Is Not Enough, and Neither Are Supplementary Interventions

Schistosomiasis is one of the five neglected tropical diseases (NTDs) that are being controlled and potentially eliminated through mass drug administration (MDA) of preventive chemotherapy (PCT), in this case praziquantel. In The Lancet Knopp et al. reported that biannual MDA substantially reduced Schistosomiasis haematobium prevalence and infection intensity but was insufficient to interrupt transmission in Zanzibar. In addition, neither supplementary snail control or behaviour change activities did not significantly boost the effect of MDA. Most MDA programs focus on school aged children, and so other groups in the community who have regular water contact would not be reached. Water and sanitation activities also have limitations. This raises the question about whether control is acceptable for public health, or if there needs to be a broader intervention to reach elimination?

Trachoma on the Way to Elimination

Speaking of elimination, WHO has announced major “sustained progress” on trachoma efforts. “The number of people at risk of trachoma – the world’s leading infectious cause of blindness – has fallen from 1.5 billion in 2002 to just over 142 million in 2019, a reduction of 91%.” Trachoma is another NTD that uses the MDA strategy.

The news about NTDs from Dengue to Schistosomiasis to Trachoma is complicated and demonstrates that putting diseases together in a category does not result in an easy choice of strategies. Do we control or eliminate or simply manage illness? Can our health systems handle the needs for disease elimination? Is the public ready to get on board?

Malaria Updates

And concerning being complicated, malaria this week again shows many facets of challenges ranging from how to recognize and deal with asymptomatic infection to preventing reintroduction of the disease once elimination has been achieved. Several reports this week showed the particular needs for malaria intervention ranging from high burden areas to low transmission verging on elimination to preventing re-introduction in areas declared free from the disease.

In South West, Nigeria Dokunmu et al. studied 535 individuals aged from 6 months were screened during the epidemiological survey evaluating asymptomatic transmission. Parasite prevalence was determined by histidine-rich protein II rapid detection kit (RDT) in healthy individuals. They found that, “malaria parasites were detected by RDT in 204 (38.1%) individuals. Asymptomatic infection was detected in 117 (57.3%) and symptomatic malaria confirmed in 87 individuals (42.6%).

Overall, detectable malaria by RDT was significantly higher in individuals with symptoms (87 of 197/44.2%), than asymptomatic persons (117 of 338/34.6%)., p = 0.02. In a sub-set of 75 isolates, 18(24%) and 14 (18.6%) individuals had Pfmdr1 86Y and 1246Y mutations. Presence of mutations on Pfmdr1 did not differ by group. It would be useful for future study to look at the effect of interventions such as bednet coverage. While Southwest Nigeria is a high burden area, the problem of asymptomatic malaria will become an even bigger challenge as prevalence reduces and elimination is in sight.

Sri Lanka provides a completely different challenge from high burden areas. There has been no local transmission of malaria in Sri Lanka for 6 years following elimination of the disease in 2012. Karunasena et al. report the first case of introduced vivax malaria in the country by diagnosing malaria based on microscopy and rapid diagnostic tests. “The imported vivax malaria case was detected in a foreign migrant followed by a Plasmodium vivax infection in a Sri Lankan national who visited the residence of the former. The link between the two cases was established by tracing the occurrence of events and by demonstrating genetic identity between the parasite isolates. Effective surveillance was conducted, and a prompt response was mounted by the Anti Malaria Campaign. No further transmission occurred as a result.”

Bangladesh has few but focused areas of malaria transmission and hopes to achieve elimination of local transmission by 2030. A particular group for targeting interventions is the population of slash and burn cultivators in the Rangamati District. Respondents in this area had general knowledge about malaria transmission and modes of prevention and treatment was good according to Saha and the other authors. “However, there were some gaps regarding knowledge about specific aspects of malaria transmission and in particular about the increased risk associated with their occupation. Despite a much-reduced incidence of malaria in the study area, the respondents perceived the disease as life-threatening and knew that it needs rapid attention from a health worker. Moreover, the specific services offered by the local community health workers for malaria diagnosis and treatment were highly appreciated. Finally, the use of insecticide-treated mosquito nets (ITN) was considered as important and this intervention was uniformly stated as the main malaria prevention method.”

Kenya offers some lessons about low transmission areas but also areas where transmission may increase due to climate change. A matched case–control study undertaken in the Western Kenya highlands. Essendi et al. recruited clinical malaria cases from health facilities and matched to asymptomatic individuals from the community who served as controls in order to identify epidemiological risk factors for clinical malaria infection in the highlands of Western Kenya.

“A greater percentage of people in the control group without malaria (64.6%) used insecticide-treated bed nets (ITNs) compared to the families of malaria cases (48.3%). Low income was the most important factor associated with higher malaria infections (adj. OR 4.70). Houses with open eaves was an important malaria risk factor (adj OR 1.72).” Other socio-demographic factors were examined. The authors stress the need to use local malaria epidemiology to more effectively targeted use of malaria control measures.

The key lesson arising from the forgoing studies and news is that disease control needs strong global partnerships but also local community investment and adaptation of strategies to community characteristics and culture.

Mobile migrant populations present a special challenge for malaria control and elimination efforts. Nguyen Ha Nam and colleagues* (Nguyen Xuan Thang, Gary Dahl, James O’Donnell, Vashti Irani, Sara Canavati, Jack Richards, Ngo Duc Thang, and Tran Thanh Duong) presented their study of this group at the recent Malaria World Congress. They are also sharing what they learned below.

Mobile Migrant Populations (MMPs) are a key population for containing the spread of malaria in the border areas between Cambodia and Vietnam. The number of imported cases in Viet Nam in 2017. 12,5% of such cases caught in Binh Phuoc and Dak Nong provinces and all of them came from Cambodia. The provinces bordering Cambodia and Vietnam have been had the highest malaria transmission intensity. This borders are frequented by MMPs who have proven difficult to target for surveillance and malaria control activities.

Mobile Outreach Teams (MOTs) provide a potential approach to target malaria elimination activities for MMPs who may not be strongly supported by the regular village-based and clinic-based health services. This work describes the implementation of MOTs in Binh Phuoc and Dak Nong Provinces, which are high-risk regions along the Viet Nam-Cambodia border. These activities were conducted as part of the Regional Artemisinin-resistance Initiative (RAI) in 2017. Each MOT was comprised of 2 Commune Health Staff and 1 Village Health Worker (VHW) from the village nearest to the outreach area.

In the first phase of the pilot, 3 communes of 2 districts in Binh Phuoc and 2 communes of 1 district in Dak Nong with highest malaria cases reported from NIMPE are selected as targeted areas. The Objectives were to …

• Design/tailor Mobile Outreach Information Education and Communication/Behaviour change communication (BCC/ IEC) Toolkit
• Intensify case detection and quality management by increasing the coverage of diagnostics and treatment for hard to reach populations
• Strengthen outreach to high-risk and under-served populations through MOT scouting activities to locate unreached Mobile Communities and map their locations
• Link MMPs with health facilities and Village Health Workers

All MOT members were provided with smartphones and were trained on how to use the EpiCollect5 app to track malaria cases, record mapping information and upload real-time reports of these malaria cases. MOTs conducted 5-day outreach activities every month. These activities began with scouting out locations of the MMP communities.

Once located, the MOTs geo-tagged the location of the community, conducted a short epidemiological survey on the community and screened for malaria using Rapid Diagnostic Tests and blood smear microscopy. Active malaria cases were provided with treatment according to the National guidelines, and Long Lasting Insecticidal Nets were distributed based on results of diagnosis and the survey.

This action has led to increased diagnosis and treatment of hard to reach MMPs with increased access by those communities to malaria services. Improved understanding and increased use of malaria prevention practices hard to reach MMP communities/households. Mapped of previously unreached MMP Communities and unofficial border crossing points with malaria transmission hotspots and highly frequented crossing identified. The number of MMPs were monitored by MOTs were 2,699 accounting for 5.18% of the population in the project sites (2,699/52,095).

These screened MMPs were almost located along the border among project communes in Bu Gia Map National Forest where have a lot of unofficial border crossers, timber camp communities, and other revolving communities. 1,977 targeted people were tested for malaria. This number was achieved 73.25% of mobile migrant people (1,977/2,699). This work highlights how MOTs can target the previously unreached populations of MMPs to strengthen malaria surveillance and active case responses to reduce malaria transmission in Viet Nam.

A system of real-time data collection of malaria cases from VHWs and MOTs using mobile phone uploads was established. Border screening and tracking hard to reach communities is a useful approach to implement to identify imported cases; however, it is labor-intensive, and misses subjects crossing at unofficial borders due to limited working time of MOTs (5 days a month).

Positive cases in Binh Phuoc province are maintained for keeping track after receiving treatment due to no confirmed cases detected in targeted communes in Dak Ngo province, though these communes mainly have numerous transient timber camps moving in deep forests, and highly mobile border-crossers moving between regions and countries frequently. Future work will combine routine support from District health staff and expand the role of VHWs with motorbike provision for each MOT in order to not only to improve their quality outreach activities but also develop stronger Active Case Detection in the next phase of the project.

*Team members represent the National Institute of Malariology, Parasitology and Entomology, Hanoi, Viet Nam; Health Poverty Action, London, UK; and the Burnet Institute, Melbourne, Australia.

References

• Kheang ST, Lin MA, et al. Malaria Case Detection Among Mobile Populations and Migrant Workers in Myanmar: Comparison of 3 Service Delivery Approaches. 2018
• Shannon Takala-Harrison,a Christopher G. Jacob, et al. Independent Emergence of Artemisinin Resistance Mutations Among Plasmodium falciparum in Southeast Asia. 2014.
• Imwong M, Hien TT, et al. Spread of a single multidrug resistant malaria parasite lineage (PfPailin) to Vietnam. 2017.
• Richard J Maude,corresponding author Chea Nguon, et al. Spatial and temporal epidemiology of clinical malaria in Cambodia 2004–2013. 2014.
• Imwong M, Nguyen TN, et al.The epidemiology of subclinical malaria infections in South-East Asia: findings from cross-sectional surveys in Thailand–Myanmar border areas, Cambodia, and Vietnam. 2015.
• Hannah Edwards, Sara E. Canavati, et al. Novel Cross-Border Approaches to Optimise Identification of Asymptomatic and Artemisinin-Resistant Plasmodium Infection in Mobile Populations Crossing Cambodian Borders. 2015.

Viet Nam is among the Asia-Pacific countries focusing on eliminating malaria. Mapping helps target malaria interventions. Nguyen Xuan Thang and colleagues (James O’Donnell, Vashti Irani, Leanna Surrao, Ricardo Ataide, Josh Tram, An Le, Sara Canavati, Tran Thanh Duong, Tran Quoc Tuy, Gary Dahl, Gerard Kelly, Jack Richards, Ngo Duc Thang) presented their pilot mapping efforts at the Malaria World Congress in Melbourne recently and below share their experiences with us.

Viet Nam is focused on eliminating malaria by 2030. Viet Nam saw a 73% reduction in cases between 2013 and 2017 (NIMPE data), yet border provinces still have a high burden of malaria. However, some provinces still have a high burden of malaria. To achieve malaria elimination, it is essential to deploy targeted interventions in these locations.

Spatial Decision Support Systems (SDSS) can be used by National Malaria programs to integrate geographic elements in the management of malaria cases and facilitate targeted malaria interventions in these high-risk settings.

The objective of this work was to pilot a SDSS system for Binh Phuoc and Dak Nong Provinces in Viet Nam to facilitate ongoing surveillance and targeted malaria, as part of the Regional Artemisinin-resistance Initiative (RAI). This objective was achieved by:

• 

  Collecting data with cell phones

  Collecting baseline GIS data at household level and environmental characteristics associated with the area;

• Establishing a routine data collection system that will be reported by mobile medical staff by mobile phone;
• Integrating this data to form a spatial decision support system (SDSS);
• Using the SDSS system for direct reporting to malaria control programs that provided strategic solutions for the prevention of disease spread and the elimination of malaria

Sample cell phone data screens

In Phase 1, a household and mapping survey was conducted in collaboration with commune, district and village health workers. Epicollect5 software was used on smartphones with GPS functionality to record mapping information (latitude and longitude) and general information on household members. During Phase 1, 10,506 households were surveyed and data was aggregated in a custom Geographic Information System (GIS) database.

The majority of the surveyed individuals were of the Kinh ethnicity (19,282; 35.4%), followed by M’Nong (4,669; 8.6%) and Mong (3,359; 6.2%). Data related to malaria among mobile populations were included in the GIS as a means to identify and describe groups at high risk for malaria e.g. forest-goers. The survey data were reviewed, cleaned and matched using the ID numbers, then aggregated with relevant administrative boundary data and linked on ArcGIS 10.2 software. This database is located in a custom GIS system and can be visualized as a spatial transmission model to support appropriate decision-making

Dots representing households

Phase 2 focused on ongoing surveillance with rapid case reporting and responses. Malaria cases diagnosed at public and local health facilities were entered into the system by Commune Health Officials. Village Health Workers were immediately notified and went to the patient’s home to undertake case investigation including further household mapping and active case detection activities. The Viet Nam National Institute of Malariology was also notified, and organized local officials to carry out an investigation into the sources of transmission (i.e. ‘hotspots’) and to implement timely interventions.

Dots representing cases

When the cases were identified, Village Health Workers went to the patient’s home to undertake operational procedures including geographic exploration, household mapping to identify the location and to identify the list of affected households. They also collected this data on EpiCollect5. Collated information on cases, transmission point, zoning of the target villages allowed for early detection of malaria outbreaks. The National Institute of Malariology can also issue guidelines when the hotspots are identified and when disease outbreaks occur

These activities are ongoing. In conclusion, a custom GIS database was developed using a household survey in Binh Phuoc and Dak Nong province of Viet Nam. Malaria cases were mapped to identify hotspots of malaria transmission and enable further active case detection and targeted interventions. This established GIS database aims to support routine case notification and to enhance the role of surveillance for active case detection and responses to achieve malaria elimination.

The authors are affiliated with the National Institute of Malariology, Parasitology, Entomology (NIMPE), Viet Nam; Burnet Institute, Australia; and Health Poverty Action, UK. Contact: xuanthang.nimpe@gmail.com

The link between malaria and food security in a global context has been made. The influence of malaria on food security was examined. Now the connection between agriculture practices/food security and malaria is pursued below.

A common complaint with programs that distribute insecticide-treated bednets to prevent malaria is that the nets may be used for other purposes that the intended effort to prevent infected mosquitoes from biting people. All informants interviewed for a study in Western Zambia reported that ITNs are regularly used for fishing and the misuse is widespread. Unsustainable fishing practices, drought and population pressure were mentioned as reasons for fishery decline. The implication was that the use of free ITNs for fishing at least saved the population money in a time of declining fortunes.

A broader review of the ITNs for fishing issue was done through contacting expert witnesses across Africa. Mosquito net fishing (MNF) was found to be a broadly pan-tropical activity, particularly prevalent in sub-Saharan Africa. The authors found that, “Perceived drivers of MNF were closely related to poverty, revealing potentially complex and arguably detrimental livelihood and food security implications.”

The mosquito breeding potential of dams cuts across Africa with the number of dams located in malarious areas projected to increase according to Kibret and colleagues. This is because “The population at risk of malaria around existing dams and associated reservoirs, is estimated to increase from 15 million in 2010 to 21-23 million in the 2020s, 25-26 million in the 2050s and 28-29 million in the 2080s.” In addition, areas with dams but without malaria transmission at present, will likely transition to regions of unstable transmission due to climate change.

Likewise, a study in Ethiopia starts with the assertion that, “Dams are important to ensure food security and promote economic development in sub-Saharan Africa,” and then stresses the importance of understanding the consequences of these projects. The researchers found that “the mean monthly malaria incidence and anopheline larval density was generally higher in the dam villages than in the non-dam villages” in all the three dam settings studied. So while dams can increase agricultural production, the authors concluded that, “the presence of dams intensifies malaria transmission in lowland and midland ecological settings.”

Hydro-agricultural projects include dams and irrigation. Human bait mosquito captures volunteers in hydro-agricultural and river bank sites in Cameroon Akono et al. found that mosquito biting rates were higher in hydro-agricultural sites of less urbanized and urban settings than in natural river banks sites. An additional implication is that urban farming, an important component of food security, may influence mosquito and malaria prevalence.

Stoler and colleagues pursued this question of urban agriculture. The odds of self-reported malaria are significantly higher for women in Accra, Ghana who are living within 1 km of urban agriculture compared with all women living near an irrigation source, the association disappearing beyond this critical distance. Likewise in Kumasi, Afrane et al. learned that “adult and larval mosquito abundance and larval survival were high in the irrigated fields in the irrigated (urban) vegetable farm. This therefore, contributed significantly to adult mosquito populations and hence malaria transmission in the city.”

Even agricultural practices in smaller subsistence farms can foster malaria mosquito breeding. Practices found in southwest Nigeria include collection of pools of water in the farms for soaking cassava tubers, digging of trenches, irrigation of farms, and the presence of fish ponds.

Communities can perceive how agricultural practices may contribute to malaria. In Tanzania a fair number of rural respondents associated growing of rice with malaria. They also noted that the need to sleep on their farms at times meant they could not benefit from the mosquito nets hanging back in their house, some hours walk away. The idea of rice cultivation and malaria was tested in central Kenya. Mwangangi and co-researchers found that, “Rice fields and associated canals were the most productive habitat types,” for malaria mosquito breeding. Overall, Mboera et al. found, “evidence that malaria transmission risk varies even between neighbouring villages and is influenced by agro-ecosystems.”

Although we can establish the two-way link or intersection between malaria and food security, we can see that recommended joint or integrated programming may not always be optimal at various levels from the nation to the community. Greater collaboration between health and agricultural ministries and agencies is needed, supported by national policies that see malaria and food production as part of overall national development goals.