Posts or Comments 05 July 2022

Archive for "Environment"

Environment &Mosquitoes Bill Brieger | 22 Apr 2022

What do mosquitoes think of Earth Day?

On Earth Day (and hopefully throughout the year) we contemplate what humans have done to ecosystems and climate. Should mosquitoes actually think about us at all, they might be grateful for the changes that increase their breeding sites.

Deforestation and modern agricultural practices favor the Anopheles group. Expanding urbanization makes life easier for the Aedes family.

Overall warming may open up new parts of the world for mosquitoes, though hotter and drier areas left behind make mosquito propagation more difficult. These highly mobile creatures may have few complaints for now, though proposed efforts to disperse particles in the atmosphere for cooling effect and current efforts to release sterile male mosquitoes into the environment might worry people as well as mosquitoes.

Human activity has modified the environment, and mosquitoes have taken advantage where they can. Environmental efforts to beat back mosquitoes need to be thought through very carefully to avoid more unintended consequences.


Agriculture &Children &Climate &Coordination &Development &Elimination &Environment &Epidemiology &Food Security Bill Brieger | 15 Apr 2022

Malaria elimination challenges around the world

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.

Agriculture &Counterfeit Drugs &Dengue &Diagnosis &Elimination &Environment &Floods &Irrigation &Mosquitoes &Severe Malaria &Surveillance &water Bill Brieger | 24 Sep 2020

Malaria News Today 2020-09-23/24

Today the issue of water is important for malaria mosquito propagation, both in irrigation and flooding. Artificial skin enables testing of mosquito biting. Fake medicines for malaria and other conditions threaten Africa’s health. Archived RDTs can aid surveillance. Finally there is concern for co-infection with both malaria and dengue leading to severe disease. Follow links below to read details.

Impact of sugarcane irrigation on malaria vector Anopheles mosquito fauna, abundance and seasonality in Arjo-Didessa, Ethiopia

Despite extensive irrigation development in Ethiopia, limited studies assessed the impact of irrigation on malaria vector mosquito composition, abundance and seasonality. This study aimed to evaluate the impact of sugarcane irrigation on species composition, abundance and seasonality of malaria vectors. Adult Anopheles mosquitoes were collected using CDC light traps from three irrigated and three non-irrigated clusters in and around Arjo-Didessa sugarcane irrigation scheme in southwestern Ethiopia.

Overall, 2108 female Anopheles mosquitoes comprising of six species were collected. The ongoing sugarcane irrigation activities in Arjo-Didessa created conditions suitable for malaria transmitting Anopheles species diversity and abundance. This could drive malaria transmission in Arjo-Didessa and its environs in both dry and wet seasons. Currently practiced malaria vector interventions need to be strengthened by including larval source management to reduce vector abundance in the irrigated areas.

Prevalence of and risk factors for severe malaria caused by Plasmodium and dengue virus co-infection

A systematic review and meta-analysis examined co-infection with both Plasmodium and dengue virus (DENV) infectious species could have serious and fatal outcomes if left undiagnosed and without timely treatment. The present study aimed to determine the pooled prevalence estimate of severe malaria among patients with co-infection, the risk of severe diseases due to co-infection, and to describe the complications of severe malaria and severe dengue among patients with co-infection. Relevant studies published between databases between 12 September 1970 and 22 May 2020 were identified and retrieved.

The present study found that there was a high prevalence of severe malaria among patients with Plasmodium and DENV co-infection. Physicians in endemic areas where these two diseases overlap should recognize that patients with this co-infection can develop either severe malaria or severe dengue with bleeding complications, but a greater risk of developing severe dengue than severe malaria was noted in patients with this co-infection.

South Sudan: Flooding deepens a humanitarian crisis in Pibor area

Today, however, the Pibor River has swelled to make parts of the town inaccessible and is threatening the clinic. Many neighborhoods cannot be reached by foot, and a local ferry is too expensive for many who live in the area. A mobile MSF team is providing medical care in hard-to-reach areas. “Our focus is now on malaria, measles and flooding,” said Josh Rosenstein, MSF deputy head of mission. “Today we are reaching out to the community through our daily mobile clinics, treating the most severe illnesses. We’re also implementing our flood contingency plan, which includes building additional flood defenses around the clinic to ensure we can continue to provide medical services, as the water level is rising at an alarming speed.”

Stratifying malaria receptivity in Bangladesh using archived rapid diagnostic tests

Surveillance of low-density infections and of exposure to vectors is crucial to understand where malaria elimination might be feasible, and where the risk of outbreaks is high. Archived rapid diagnostic tests (RDTs), used by national malaria control and elimination programs for clinical diagnosis, present a valuable, yet rarely used resource for in-depth studies on malaria epidemiology. 1022 RDTs from two sub-Districts in Bangladesh (Alikadam and Kamalganj) were screened by qPCR for low-density Plasmodium falciparum and Plasmodium vivax infections, and by ELISA for Anopheles salivary gland antibodies as a marker for exposure to vectors.

Concordance between RDT and qPCR was moderate. qPCR detected 31/1022 infections compared to 36/1022 diagnosed by RDT. Exposure to Anopheles was significantly higher in Kamalganj despite low transmission, which could be explained by low bed net use. Archived RDTs present a valuable source of antibodies for serological studies on exposure to vectors. In contrast, the benefit of screening archived RDTs to obtain a better estimate of clinical case numbers is moderate. Kamalganj could be prone to outbreaks.

New tool mimics human skin to allow detailed study of mosquito biting

eLife: Researchers develop a human skin mimic to study mosquito biting in high resolution without using humans as ‘bait.’ The tool, which uses an artificial blood meal and a surface that mimics human skin, will provide detailed understanding of blood feeding without using human subjects as bait. It can also fit conveniently into a backpack, allowing the study of mosquitoes in laboratory and natural environments.

Blood feeding is essential for mosquitoes to reproduce, but it is during blood feeds on human hosts that they pass on pathogens such as malaria. It consists of a bite ‘substrate’ – a transparent, temperature-controlled surface that mimics body temperature to attract mosquitoes. An artificial meal is applied on top of this and covered with a commonly used membrane that mosquitoes can pierce. The meal resembles blood, allowing mosquitoes to engorge and increase their weight by two to threefold. This bite substrate is then placed in a transparent cage, and an external camera records the mosquitoes’ behaviour. The team tested biteOscope with four medically important species of mosquito.

Counterfeiting of Fake Drugs in Africa: current situation, causes and countermeasures

The more desirable a product is the higher the tendency to replicate it and meet that parcel of consumers that want to join the trend but cannot pay the price. Profit is one of the many reasons that make counterfeit an attractive business for many.  Africa, unfortunately but not surprisingly, is one of the most affected continents, comprehensible since its markets have become a huge target for second generation goods, with a major focus on pharmaceutical drugs.

The World Health Organization (hereinafter, WHO) stated that 42% of all fake medicine reported to them between the years of 2013 and 2017 was linked to the African continent and we expect that these numbers fall short of reality. Africa is seriously affected by it and one clear example is the anti-malarial medication. Anti-malarials and antibiotics are amongst the most commonly reported as fake or substandard medical products.

Climate &COVID-19 &Dengue &Diagnosis &Environment &Invest in Malaria Control &Mapping &mHealth &Migration &Mosquitoes &Nomadic People &Surveillance Bill Brieger | 11 Sep 2020

Malaria News Today 2020-09-11

Today’s news and abstracts look at a variety of issues ranging from overall malaria funding funding needs to the effect of climate change on different types of mosquitoes and the diseases they carry (e.g. malaria vs dengue). We also examine the need for surveillance among nomadic groups and the use of cell phones in a saliva based malaria testing system. Please click the links below to read more on each subject.

Rwanda: Government Needs U.S.$70 Million to Fill Malaria Financing Gap

By Nasra Bishumba: The Government needs $73 million to bridge the funding in the funds needed to fight malaria between 2020 and 2024, The New Times can reveal. The Rwanda National Strategic Plan 2020-2024 to fight malaria drawn up in June this year indicates that although the implementation requires Rwf295bn ($280 million), the government already has funding commitment to the tune of $206.8m (equivalent to 74 per cent).

According to the strategic plan, a copy of which The New Times has seen, this leaves a gap of $73m which it hopes to mobilize from different sources. With these funds, the government is seeking to protect at least 85 per cent of the population with preventive interventions and to work towards promptly testing and treating suspected malaria cases by 2024. To achieve this, the biggest chunk of the funds will be invested in malaria prevention to a tune of $186m, an equivalent of 66 per cent of the entire budget.

Climate Change May Shift Risks of Mosquito-borne Diseases

By Asher Jones: More dengue, less malaria. That may be the future in parts of Africa on a warming planet, depending on where you live. New research says it’s all about which mosquitoes will thrive. And the methods to control one don’t necessarily work on the other.

The mosquito that spreads malaria prefers relatively cool temperatures of 25 degrees Celsius (77 degrees Fahrenheit). The dengue mosquito does best at 29 degrees Celsius (84.2 degrees Fahrenheit). Because of this difference in optimal temperatures, “We would actually predict that climate change might have opposing effects [on disease transmission],” said Erin Mordecai, assistant professor of biology at Stanford University and lead author on the study. “Climate change might make it less suitable for malaria to be transmitted but more suitable for dengue to be transmitted.”

Africa’s Nomadic Pastoralists and Their Animals Are an Invisible Frontier in Pandemic Surveillance

@ASTMH The effects of COVID-19 have gone undocumented in nomadic pastoralist communities across Africa, which are largely invisible to health surveillance systems despite the fact that they are of key significance in the setting of emerging infectious disease. We expose these landscapes as a “blind spot” in global health surveillance, elaborate on the ways in which current health surveillance infrastructure is ill-equipped to capture pastoralist populations and the animals with which they coexist, and highlight the consequential risks of inadequate surveillance among pastoralists and their livestock to global health. As a platform for further dialogue, we present concrete solutions to address this gap.

Mobile phone-based saliva test wins NIH prize

Cornell researchers’ concept for a quick, non-invasive, mobile phone-based system to detect infectious diseases, inflammation and nutritional deficiencies in saliva was awarded a $100,000 National Institutes of Health Technology Accelerator Challenge prize. The NIH’s prize challenge encourages the development of new, non-invasive diagnostic technologies important for global health. For the group’s saliva-based test, a small 3D-printed adapter is clipped to a mobile phone and synced with a mobile app. The app uses the phone’s camera to image test strips to detect malaria, iron deficiency and inflammation, with results in under 15 minutes.

The proposal builds on the FeverPhone and NutriPhone platforms developed by the team at Cornell’s Institute for Nutritional Sciences, Global Health and Technology (INSiGHT). The technologies, funded by the NIH and the National Science Foundation, evaluate infections and nutritional status using blood. According to Mehta, technologies using salivary biomarkers could revolutionize how conditions such as malaria and iron deficiency are identified and addressed, especially in settings where access to primary health care and traditional, laboratory-based tests is limited.

Monsoon infections: How to tell the difference between dengue and malaria? Watch out for these symptoms

While both diseases are mosquito-borne and cause similar symptoms such as fever, joint/muscle pain, headaches, and fatigue, some differences between their symptoms can help you identify the specific infections. Unique symptoms of Malaria: Stomach problems such as vomiting, Diarrhoea, Dry cough, Shivering, Spleen enlargement Unique symptoms of Dengue: Pain behind the eyes, Swollen glands, Rashes

Diagnosis &Elimination &Environment &Health Information &Health Systems &History &Invest in Malaria Control &Microscopy &Surveillance &Trachoma Bill Brieger | 10 Sep 2020

Malaria News Today 2020-09-10

These malaria and related news and abstracts stress the importance of sentinel surveillance systems, strong political and systems commitment to disease elimination, malachite green loop-mediated isothermal amplification for better malaria detection, and the threat of neglected fungal infections. An article from The Lancet shows that it is not just money that is needed to eliminate malaria, but better management and systems. Finally a bit of history from 18th Century North Carolina is shared. Click the links in each section to learn more about each topic.

Implementation of a malaria sentinel surveillance system in Togo: a pilot study

Since July 2017, 16 health facilities called sentinel sites, 4 hospitals and 12 peripheral care units located in 2 epidemiologically different health regions of Togo, have provided weekly data on malaria morbidity and mortality for the following 3 target groups:?<?5-years-old children,???5-years-old children and adults, and pregnant women. Data from week 29 in 2017 to week 13 in 2019 were analysed.

Each sentinel site provided complete data and the median time to data entry was 4 days. The number of confirmed malaria cases increased during the rainy seasons both in children under 5 years old and in children over 5 years old and adults. Malaria-related deaths occurred mainly in children under 5 years old and increased during the rainy seasons. The mean percentage of tested cases for malaria among suspected malaria cases was 99.0%. The mean percentage of uncomplicated malaria cases handled in accordance with national guidelines was 99.4%. The mean percentage of severe malaria cases detected in peripheral care units that were referred to a hospital was 100.0%. Rapid diagnostic tests and artemisinin-based combination therapies were out of stock several times, mainly at the beginning and end of the year. No hospital was out of stock of injectable artesunate or injectable artemether.

These indicators showed good management of malaria cases in the sentinel sites. Real-time availability of data requires a good follow-up of data entry on the online platform. The management of input stocks and the promptness of data need to be improved to meet the objectives of this malaria sentinel surveillance system.

Evaluation of the colorimetric malachite green loop-mediated isothermal amplification (MG-LAMP) assay …

… for the detection of malaria species at two different health facilities in a malaria endemic area of western Kenya. Prompt diagnosis and effective malaria treatment is a key strategy in malaria control. However, the recommended diagnostic methods, microscopy and rapid diagnostic tests (RDTs), are not supported by robust quality assurance systems in endemic areas. This study compared the performance of routine RDTs and smear microscopy with a simple molecular-based colorimetric loop-mediated isothermal amplification (LAMP) at two different levels of the health care system in a malaria-endemic area of western Kenya.

Patients presenting with clinical symptoms of malaria at Rota Dispensary (level 2) and Siaya County Referral Hospital (level 4) were enrolled into the study after obtaining written informed consent. Capillary blood was collected to test for malaria by RDT and microscopy at the dispensary and county hospital, and for preparation of blood smears and dried blood spots (DBS) for expert microscopy and real-time polymerase chain reaction (RT-PCR).

Results of the routine diagnostic tests were compared with those of malachite green loop-mediated isothermal amplification (MG-LAMP) performed at the two facilities.
A total of 264 participants were enrolled into the study. At the dispensary level, the positivity rate by RDT, expert microscopy, MG-LAMP and RT-PCR was 37%, 30%, 44% and 42%, respectively, and 42%, 43%, 57% and 43% at the county hospital. Using RT-PCR as the reference test, the sensitivity of RDT and MG-LAMP was 78.1% (CI 67.5–86.4) and 82.9% (CI 73.0–90.3) at Rota dispensary.

At Siaya hospital the sensitivity of routine microscopy and MG-LAMP was 83.3% (CI 65.3–94.4) and 93.3% (CI 77.9–99.2), respectively. Compared to MG-LAMP, there were 14 false positives and 29 false negatives by RDT at Rota dispensary and 3 false positives and 13 false negatives by routine microscopy at Siaya Hospital. MG-LAMP is more sensitive than RDTs and microscopy in the detection of malaria parasites at public health facilities and might be a useful quality control tool in resource-limited settings.

Terminating Trachoma. How Myanmar eliminated blinding trachoma.

Download the book  from WHO New Delhi: World Health Organization, Regional Office for South-East Asia; 2020. Licence: CC BY-NC-SA 3.0 IGO.  Myanmar’s three-phase approach to eliminating trachoma has been a great success, which will certainly continue. The country’s visionary National Eye Health Plan 2017-2021, which is closely aligned with international policies for prevention of blindness, gives confidence that Myanmar will maintain its elimination status. This book chronicles how a combination of good leadership, effective partnerships, health-care facilities and hardworking health-care personnel helped Myanmar eliminate trachoma as a public health problem.

Health sector spending and spending on HIV/AIDS, tuberculosis, and malaria, and development assistance for health, SDG Progress

Although the progress towards Sustainable Development Goal (SDG) 3, which aims to “ensure healthy lives and promote well-being for all at all ages”, has been assessed in various works, there is less research focusing on tracking spending towards this goal. In this study, spending estimates were used to determine progress in financing the priority areas of SDG3, examine the correlation between outcomes and financing, and identify where resource gains are most required to attain the SDG3 indicators for which data are available.

From 1995 to 2017, domestic health spending was determined, disaggregated by source (government, out-of-pocket, and prepaid private) for 195 countries and territories. Outcomes suggest a global rise in total health spending since the state of the SDGs in 2015, reaching $7·9 trillion (7·8–8·0) in 2017, and is estimated to rise to $11·0 trillion (10·7–11·2) by 2030, although with substantial disparity across countries. Per estimates, low-income and middle-income countries, in 2017, had an estimated spending of $20·2 billion on HIV/AIDS, $10·9 billion on tuberculosis, and $5·1 billion on malaria in endemic countries.

Although there is an increase in both domestic government and DAH spending, across these three diseases, variation in the accompanied changes in outcomes was observed. Malaria was noted to have the most consistent reductions in outcomes across countries as spending has raised. Findings thereby suggest mixed progress towards meeting the SDG3 targets; the progress varied by country and by target. The evidence on the scale-up of spending and improvements in health outcomes suggest a nuanced relationship, such that outcomes do not always improve with increases in spending.

Although more resources may be required by the countries to achieve SDG3, there will also be a necessity for addressing other constraints in the broader health system such as inefficient allocation of resources across interventions and populations, weak governance systems, human resource shortages, and drug shortages.

Ignored fungal infections kill more people annually than HIV and malaria combined

Carolina Pohl-Albertyn says that, “You may also know that there are other infections causing great concern, such as HIV (690 000 deaths/year), tuberculosis (1.5-million deaths/year), and malaria (405,000 deaths/year). But what would be your reaction if you knew that fungal infections (ranging from skin and mucosal infections (e.g. vaginal or oral thrush) to deadly systemic and organ infections (e.g. candidiasis, cryptococcal meningitis, and bronchopulmonary aspergillosis]) affect more than one-billion people each year, of which more than 150-million cases are severe and life-threatening and cause 1.7 million deaths per year?”

Malaria was once scourge in Chowan County, North Carolina

Nicole Bowman-Layton (Editor) provides some history of malaria. It’s fascinating to think that less than 100 years ago this disease was still a major scourge in Chowan County. I’ve wanted to write about this topic for a long time since the coronavirus popped up but was a bit concerned about writing about a somewhat depressing topic.

According to NCPedia malaria came to North Carolina in the 1500s from some of the first European explorers who were bitten by our friendly Anopheles mosquitoes and then transmitted to the native population. And as we well know, we live in a very damp environment surrounded by sitting water which certainly increases the harvest of mosquitos. Some of the most prominent Revolutionary Edentonians suffered from the “Ague” during their lives. Declaration signer Joseph Hewes suffered from “intermittent fever and ague” throughout his life which were certainly symptoms of malaria.

The German traveler Dr. Johan Schoepf wrote in his book Travels in the Confederation, 1783-1784, of “…the sickliness of the inhabitants, especially prevalent in the low, overflowed, and swampy parts of this country, and giving the people a pale, decayed, and prematurely old look. This is the case not only about Edenton, but along the entire low-lying coast, which this fall, from Virginia to South Carolina, was visited with numerous fevers.

Borders &Diagnosis &Elimination &Environment &Gender &Health Education &Health Workers &Indoor Residual Spraying &IRS &ITNs &Mosquitoes &Plasmodium/Parasite &Vector Control Bill Brieger | 07 Jul 2019

The Weekly Tropical Health News 2019-07-06: Eliminating Malaria in Low Transmission Settings

This week started with articles that drew attention to the challenges of malaria in low transmission areas and with low density infections. Malaria Journal has provided several insightful articles toward this end.

Being an island has certainly helped Zanzibar make progress toward malaria elimination as witness the fact that malaria prevalence has remained below 1% for the past decade. Not only does Zanzibar still face threats of infection from the mainland, it may also experience an upsurge locally if residual transmission and the role of human behavior and community actions are not well understood. April Monroe et al. conducted in-depth interviews with community members and local leaders across six sites on Unguja, Zanzibar as well as semi-structured community observations of night-time activities and special events to learn more.

While there was high reported ITN use, there were also times when people were exposed t mosquitoes while being outdoors during biting times. This could be around the house, or at special night events like such as weddings, funerals, and religious ceremonies. Men spent more time outdoors than women. Clearly appropriate interventions and needed and should be promoted in culturally appropriate ways in order to further reduce and eventually eliminate transmission.

Angela Early and colleagues presented findings on a diagnostic process of deep sequencing for understanding the dynamics and complexity of Plasmodium infections, but stress that knowing the lower limit of detection is challenging. They present “a new amplicon analysis tool, the Parallel Amplicon Sequencing Error Correction (PASEC) pipeline, is used to evaluate the performance of amplicon sequencing on low-density Plasmodium DNA samples.”

The authors learned that, “four state-of-the-art tools resolved known haplotype mixtures with similar sensitivity and precision.” They also cautioned that, “Samples with very low parasitemia and very low read count have higher false positive rates and call for read count thresholds that are higher than current default recommendations.” Better understanding of the genetic mix of plasmodium infections as countries move toward low transmission and elimination is crucial for selecting appropriate interventions and evaluating their outcomes.

Hannah Edwards and co-researchers examined conditions for malaria transmission along the Thailand-Myanmar border in areas approaching malaria elimination. While prevalence may be less than 1%, residual transmission still occurs. Transmission occurs not only around residences but in the forests where people work. The researchers therefore looked at the behavior of both humans and insects. Overall, they found that, “Community members frequently stayed overnight at subsistence farm huts or in the forest. Entomological collections showed higher biting rates of primary vectors in forested farm hut sites and in a more forested village setting compared to a village with clustered housing and better infrastructure.”

While mosquitoes preferred to bite inside huts, their threat was magnified by those who did not use long lasting insecticide-treated nets (LLINs). While out in the farms and forests, people tended to wake early and increase their likelihood of being bitten. The authors discuss the challenges of dual residences in terms of LLIN ownership and even concerning the potential access to indoor residual spraying. The definition for universal net coverage needs to expand from one net per two people to include adequate nets wherever people are located.

The Amazonian area of Brazil is another area working toward malaria elimination, in particular, Plasmodium vivax. Felipe Leão Gomes Murta et al. also looked at the human side of the equation and identified misperceptions by both community members and health workers that could inhibit elimination efforts. They found, “many myths regarding malaria transmission and treatment that may hinder the sensitization of the population of this region in relation to the use of current control tools and elimination strategies, such as mass drug administration (MDA),” and LLINs.

Problematic perceptions included mention by both groups that the use of insecticide-treated nets, may cause skin irritations and allergies. Both community members and health professionals said malaria is “an impossible disease to eliminate because it is intrinsically associated with forest landscapes.” They concluded that such perceptions can be a barrier to control and elimination.

Efforts to eliminate malaria from low transmission settings are an essential to the overall global goals. These four articles tell us that close attention to and better understanding of humans, parasites and mosquitoes is still needed to achieve these goals.

Climate &Environment &Mosquitoes &Zoonoses Bill Brieger | 22 Apr 2017

Earth Day, Climate, Environment and Malaria

The Earth Day website notes that, “Our planet is currently losing over 15 billion trees each year—that’s 56 acres of forest every minute. We’re working hard to reverse that trend by supporting global reforestation projects. Earth Day Network’s Reforestation Campaign benefits local communities, increases habitat for species, and combats climate change.”

This habitat change if often conducive to the spread of malaria in areas and among populations that may not have been affected before. Specifically, “More risks associated with El Niño are: flooding and landslides in the Americas, drought in Southeast Asia and Australia, scrambled fisheries, and malaria, cholera, and dengue outbreaks.”

Terry Devitt reported that the incidence of malaria jumps when Amazon forests are cut, establishing a firm link between environmental change and human disease. The report, which combines detailed information on the incidence of malaria in 54 Brazilian health districts and high-resolution satellite imagery of the extent of logging in the Amazon forest, shows that clearing tropical forest landscapes boosts the incidence of malaria by nearly 50 percent (according to Olson and colleagues).

Moyes et al. Predicted the geographical distributions of the macaque hosts and mosquito vectors of Plasmodium knowlesi malaria in forested and non-forested areas of Southeast Asia.  When urbanization and deforestation bring people into habitats they never lived in, zoonotic transmission of malaria results. Fornace et al. similarly observed that, “Marked spatial heterogeneity in P. knowlesi incidence was observed, and village-level numbers of P. knowlesi cases were positively associated with forest cover and historical forest loss in surrounding areas. These results suggest the likelihood that deforestation and associated environmental changes are key drivers in P. knowlesi transmission in these areas” of Malaysia.

Back to Brazil, de Alvarenga  and co-researchers reported in the transmission of Plasmodium simian malaria in the Brazilian Atlantic forest as a natural infection of capuchin monkeys (Cebinae subfamily). Because of human movement into forest areas, cases among people have now been documented.

The zoonotic transmission of malaria to humans due to changes in climate, environment and habitat pose another unwanted challenge to global efforts to eliminate malaria. On Earth Day it is imperative for malaria control and elimination workers to collaborate closely with colleagues in environmental health and protection.

Environment &Integrated Vector Management &Mosquitoes Bill Brieger | 20 Aug 2015

World Mosquito Day Is Not Just About Malaria

World Mosquito Day Block the BiteOur colleagues at Roll Back Malaria remind is that 20 August is marked annually as World Mosquito Day since doctor Sir Ronald Ross first identified female Anopheles mosquitoes as the vector that transmits malaria between humans. This year, 2015 is the 118th annual observance.

It may seem obvious to state, but while malaria is carried by mosquitoes, not all types of mosquitoes carry malaria. And more specifically our control measures for combating the anopheles mosquitoes that carry malaria are not specifically aimed at aedes or culex. This has not stopped public health workers in the field, and health worker trainees in the classroom from broadcasting messages to the public implying that the control and destruction of any mosquito will prevent malaria.

In terms of health communication, if we convince people that any mosquito carries malaria, but institute measures like long lasting insecticide-treated nets and indoor residual spraying aimed at anopheles mosquitoes, we may lose some credibility as people will still see other types of mosquitoes flying about. And then when people develop another febrile illness from bites of those other mosquitoes, they may not differentiate illness types, but say our interventions do not work.

Old poster on malaria-mosquito presentionThe conflation of all mosquitoes with malaria is seen clearly in the image at the right from a common malaria poster. The dirty gutters may contain culex larvae; the cans and bottles may contain aedes larvae. Obviously none of these mosquito species is good for human health, so can we achieve clarity in health communication about mosquito-borne disease on World Mosquito Day and thereafter?

We often forget that people in the community are quite observant of their environment; sometimes more so the the public health inspectors who try to teach them about ways of preventing malaria by reducing mosquito breeding. Villagers deal with mosquitoes on a daily basis and can distinguish the coloring and posture of the different species.

Instead of telling people what to do, it would be more helpful for public health workers to engage in dialogue with people to learn what they know about different types of mosquitoes and different forms of febrile illness. Maybe by learning first from the people, health workers can then become better teachers about integrated vector management.

PS – maybe we can also educate the mass media to stop putting pictures of Aedes aegypti on their malaria stories!

Environment &Epidemiology &Surveillance Bill Brieger | 19 Aug 2015

Beyond Garki baseline results released, highlighting changes in malaria environment

Ilya Jones shares with us the latest update on Malaria Consortium’s Beyond Garki project that seeks to understand changes in malaria epidemiology and recommend effective strategies to improve control efforts ……

201506110316-malariometric-bannerOver the last 15 years, increased global investment in fighting malaria has contributed substantially to reduction in the prevalence of the disease in endemic countries around the world. With the development of new technologies and innovative approaches to disease control, there is more hope than ever that malaria will be eliminated in places where it used to be a major public health threat.

However, sustaining momentum requires a deep understanding of the changes in the frequency of the disease, determinants of transmission and impact of interventions in a changing environment. Understanding these changes is essential in order to tailor health interventions to be as effective as possible.

Malaria Consortium’s Beyond Garki project, funded by the UK government through the Programme Partnership Arrangement (PPA), seeks to understand changes in malaria epidemiology and recommend strategies to improve malaria control efforts. The project is named after the efforts of the World Health Organization and the government of Nigeria to study the epidemiology and control of malaria in Garki, Nigeria between 1969 and 1976. Beyond Garki began in Uganda and Ethiopia in 2012, with four survey rounds conducted to date. Additional studies were also carried out in Cambodia, and more studies are planned in Nigeria. Each survey tracks changes in malaria epidemiology over time and will ideally inform strategic decisions on the use of interventions.

The baseline results have been made available and will serve as a point of comparison for data obtained from subsequent survey rounds, which will be released in the autumn. However the results of the baseline survey are interesting in their own right. Some of the highlights are listed below:

  • Low to moderate malaria transmission intensity was observed in all sites. In Ethiopia, P. vivax was found to be a predominant malaria species, probably due to decline in transmission over recent years.
  • High coverage of insecticide treated nets (ITNs)was observed in three of four sites but it is still not at an ideal level.
  • ITN use rates among household members that had access were generally quite high. The studyNet use and infection also showed there is willingness to buy nets, at least in the Uganda sites.
  • In Uganda, a major vector of malaria, A. gambiae s.s., has developed resistance against pyrethroids.
  • Most human-vector contact still occurs indoors. However, there is a tendency of early biting of A. funestus s.l. in one of the sites in Uganda. More information is needed to determine the biting and resting habits of vector species in both countries.
  • The rate of malaria diagnosis using microscopy and rapid diagnostic tests (RDTs) has been strengthened in all sites. RDTs have been found to effectively predict negative malaria results, indicating that service providers should pay attention to other causes of fever when RDT negative results are reported for patients.
  • The level of use of intermittent preventive treatment of pregnant women (IPTp) needs to be strengthened in Uganda.

beyond garkiTo learn more about the project, the methods used to collect data, the findings and the recommendations, check out the dedicated microsite for Beyond Garki here, or read the baseline report here.

Environment &IPTi Bill Brieger | 14 Jun 2013

Malaria and the Rains of Africa

The World Health Organization is guiding countries across the Sahel of Africa to begin piloting ‘seasonal malaria chemoprevention” or SMC. We recently featured this in the May 2013 issue of Africa Health. WHO explains that “Seasonal malaria chemoprevention is defined as the intermittent administration of full treatment courses of an antimalarial medicine to children during the malaria season in areas of highly seasonal transmission.” This is an outgrowth of several years of research into intermittent preventive treatment for infants (IPTi) and children.

dscn8811a.jpgMalaria program managers wanted a more focused application of IPTi where it would be likely to make a major impact on disease control. Researchers found that areas meeting malaria seasonality definition of 60% of annual incidence within 4 consecutive months were observed more frequently in the Sahel and sub-Sahel than in other parts of Africa, and thus could provide an ideal focus for intervention.

What makes transmission more intense in those four months is the rainy season.  Ironically we have recently seen a more intense rainy season in the Sahel with serious flooding. IRIN reports that, “The African Centre of Meteorological Applications for Development (ACMAD) in a seasonal weather outlook says near-average or above-average rainfall is likely over the western Sahel, which stretches across Mauritania, Senegal and western and central Niger. These regions are ‘expected to be the area with the highest risk of above average number of extreme precipitating events that may lead to flash floods’.”

What does this flooding mean for SMC?  While breeding mosquitoes obviously need the pools that rainwater creates, too much rain may have an opposite effect with flash floods washing out breeding sites (let alone homes and possessions). When flooding results in larger and longer collections of standing water, mosquito breeding may be enhanced, but this will make logistical support for training, supervision, and drug supplies extremely difficult in the region.

dscn8824a.jpgThe Sahel is one of the areas in Africa where we might hope for some early progress toward malaria elimination. With global climate changes affecting the region we can only wonder whether the weather will cooperate and allow timely implementation of new interventions.  As IRIN implies – contingency planning is extremely important.

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