Anemia &Diagnosis &Elimination &Epidemiology &Genetics &Integrated Vector Management &IPTp &Malaria in Pregnancy &Plasmodium knowlesi Bill Brieger | 26 Oct 2020
Malaria News Today 2020-10-26: Haiti, India, Malaysia, Cape Verde
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.
Anemia &coronavirus &COVID-19 &IPTp &IRS &ITNs &Larvicide &Malaria in Pregnancy &Morbidity &Mortality &Mosquitoes &Sahel Bill Brieger | 03 Oct 2020
Malaria News Today 2020-10-02/03
Recent news and abstracts include mosquito control using solar disruption of of larval habitats and plants that repel the insects around homes. The challenges of malaria related anemia in pregnancy is discussed. Malaria cases increase in Mali and Mozambique, but in the latter, deaths actually decrease. Malaria parasites have ways of making people more attractive to mosquito bites. Finally covid-19 has not disrupted malaria work as much as anticipated. Read more at the links in the sections below.
Improved Mosquito Control with Solar Power Machine that Causes Ripple Effect
Kristina Panos writes that mosquito haters of the world, rejoice! A few years ago we told you about the first version of this solar-powered mosquito repellent that works by disturbing the surface of standing water. Since then, the project has received worldwide attention, and [Pranav] is back with Solar Scare Mosquito version 2.0 in time for the the 2020 Hackaday Prize.
The idea’s still the same as before: let mosquitoes lay their eggs in the standing waters of tanks and swamps, then disturb the water with vibrations so the larvae on the surface can’t breathe. As smart as this simple idea is, version 2.0 is even smarter. It has a microphone that listens to the wing-beat frequencies of mosquitoes that like to hang around places like that. Inside there’s an Arduino MKR GSM to run the ripple-generating air pump, detect water from the sensor, and gather data from the microphone.
With a network of these devices all reporting data, [Pranav] envisions an early warning system for mosquito-borne epidemics that works by alerting the locals through their phones. Solar Scare Mosquito has come a long way since 2014.
Malaria cases spike in northern Mali
Malaria cases in northern Mali have spiked, according to medical workers, claiming 23 lives in the often lawless desert region last week alone. Mali’s ministry of health said this week that 59 people have died of malaria in the north since the start of the year, almost double the number of deaths over the same period last year.
Already struggling to curb coronavirus, the poor Sahel country is also fighting a brutal jihadist insurgency active in the north and centre of the country.
A powerful attractant: Malaria parasites lure blood-sucking mosquitoes
The malaria parasite’s gametocyte-stage has been demonstrated in the field to heavily manipulate the blood-seeking behaviour of vector mosquitoes through increasing the appeal of biting an infected host.
Plasmodium parasites, the causative agents of Malaria in humans and animals, are well known for manipulating both their human and mosquito hosts as a way of maximising the probability of interactions between them, thereby increasing the chance malaria parasites are transmitted from host to host. One way in which these devious parasites have been shown to increase the probability of host interaction is during their transmissible (gametocyte) stage.
This is achieved by inducing host red blood cells to produce volatile compounds that attract malarial vector species, such as mosquitos in the Anopheles family. The increase in production of volatile compounds, such as certain aldehydes and terpenes, by host red blood cells was shown back in 2017 to be specifically induced by a gametocyte-produced molecule called (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate, also known as HMBPP.
Malaria campaigns fight off Covid disruptions to deliver programmes
Almost all planned work against the disease has gone ahead this year, delivering nets, drugs and the world’s first malaria vaccine. More than 90% of anti-malaria campaigns planned this year across four continents are on track, despite disruptions caused by the coronavirus pandemic, according to new research.
The delivery of insecticide-treated nets and provision of antimalarial medicines in the majority of malaria-affected countries across Africa, Asia and the Americas were still going ahead, a high-level meeting organised by the RBM Partnership to End Malaria heard on Thursday.
Malaria associated with increased prevalence of anemia during pregnancy
Ken Downey Jr. and colleagues conducted a study in seven sub-Saharan African countries demonstrated an association between malaria and an increased prevalence of anemia among pregnant women, according to findings published in BMC Pregnancy and Childbirth.
“Pregnant women in sub-Saharan Africa suffer a double burden of malaria and HIV infections, and these infections interact with each other to cause anemia,” Ssentongo told Healio. “If not treated, the risk of the mother and the unborn baby dying is high. Multipronged strategies to prevent and treat malaria in HIV pregnant women are critical to ensure the survival of the mothers and their unborn babies.”Paddy Ssentongo, MD, MPH, a research assistant professor at Penn State University,
Mozambique: Malaria Cases Increase, Malaria Death Toll Declines
From January to August, 442 people in Mozambique are known to have died from malaria, according to Health Minister Armindo Tiago. Speaking at the launch of a National Home Spraying Campaign, Tiago said the malaria death toll, in the first eight months of the year, was significantly lower than that recorded in the same period in 2019, when 562 people died of the disease.
But although fewer people are dying of malaria, the number of malaria cases has actually increased – from 7.86 million cases in January-August 2019 to 8.36 million in the same months this year. The number of cases rose by 6.4 per cent, but the number of deaths fell by 21.4 per cent. Thus there is the drive to persuade families to change their behaviour.
The Plants That Keep Mosquitoes Away
Protect outdoor areas from mosquitoes and bugs to enjoy evenings outside. Including the following plants in a home garden can provide homeowners with some important weapons in the war against mosquitoes.
1. Citronella Plants: You may already be familiar with citronella plants, as they are known for emitting a strong smell that mosquitoes find objectionable. This group of plants contain citronellal, the active ingredient commonly found in mosquito repellents like citronella patio candles or sprays.
2. The Mint Family: Some members of the mint family have the power to repel mosquitoes, or at least take the sting out of their bites. Check Lemon Balm, Peppermint, Basil, Lavender, Sage, and Catnip.
3. Flowers: Believe it or not, ornamental plants can actually do double duty and function as mosquito repellents. Even better, these plants love sun and are drought resistant. Marigolds, and their relative, tarragoncontain pyrethrum, an ingredient found in many insect repellents. Verbena is a lemon-scented, easy-to-grow perennial. Citrosum is also named “the mosquito plant,” and is one of the best plants in the game for repelling mosquitoes.
Anemia &Culture &Diagnosis &immune system &Indigenous Medicine &Malaria in Pregnancy &Mosquitoes &Self-Treatment &Social/Cultural &Surveillance Bill Brieger | 19 Sep 2020
Malaria News Today 2020-09-18/19
Several reports and studies aim to help understand the malaria parasite and the human behavior surrounding its control. Cultural perceptions in Benin influence treatment seeking. Tracking cases in India aid in elimination efforts. The contrasts between in vivo and in vitro studies are examined. The factors associated with anemia among children and women in Ghana are traced to malaria and other factors. Finally both human and mosquito immunity are discussed. Click the links in each section to read details.
Demonstration of indigenous malaria elimination through Track-Test-Treat-Track (T4) strategy in a Malaria Elimination Demonstration Project in Mandla, Madhya Pradesh
Using the current intervention and prevention tools along with optimum utilization of human resources,This project has revealed about 91% reduction of indigenous cases of malaria during the period from June 2017 to May 2020, through case management and vector control strategies. A total 357,143 febrile cases were screened, out of which 0.19% were found positive.
The reduction was similar in the three high prevalence blocks of the district. These results reveal that malaria elimination is achievable in India within a stipulated time frame. The reduction of malaria at the community level was further validated when zero malaria cases were diagnosed during hospital and community-based studies in Mandla. Prompt detection and treatment of imported/migratory cases may have prevented outbreaks in the district. This project has demonstrated that field programmes backed by adequate technical, management, operational, and financial controls with robust monitoring are needed for achieving malaria elimination.needed for achieving malaria elimination.
Risk factors for anaemia among Ghanaian women and children vary by population group and climate zone
Anaemia has serious effects on human health and has multifactorial aetiologies. This study aimed to determine putative risk factors for anaemia in children 6-59 months and 15- to 49-year-old non-pregnant women living in Ghana. Data from a nationally representative cross-sectional survey were analysed for associations between anaemia and various anaemia risk factors. National and stratum-specific multivariable regressions were constructed separately for children and women to calculate the adjusted prevalence ratio (aPR) for anaemia of variables found to be statistically significantly associated with anaemia in bivariate analysis. Nationally, the aPR for anaemia was greater in children with iron deficiency (ID; aPR 2.20; 95% confidence interval [CI]: 1.88, 2.59), malaria parasitaemia (aPR 1.96; 95% CI: 1.65, 2.32), inflammation (aPR 1.26; 95% CI: 1.08, 1.46), vitamin A deficiency (VAD; aPR 1.38; 95% CI: 1.19, 1.60) and stunting (aPR 1.26; 95% CI: 1.09, 1.46).
In women, ID (aPR 4.33; 95% CI: 3.42, 5.49), VAD (aPR 1.61; 95% CI: 1.24, 2.09) and inflammation (aPR 1.59; 95% CI: 1.20, 2.11) were associated with anaemia, whereas overweight and obese women had lower prevalence of anaemia (aPR 0.74; 95% CI: 0.56, 0.97). ID was associated with child anaemia in the Northern and Middle belts, but not in the Southern Belt; conversely, inflammation was associated with anaemia in both children and women in the Southern and Middle belts, but not in the Northern Belt. Anaemia control programmes should be region specific and aim at the prevention of ID, malaria and other drivers of inflammation as they are the main predictors of anaemia in Ghanaian children and women.
From Circulation to Cultivation: Plasmodium In Vivo versus In Vitro
Research on Plasmodium parasites has driven breakthroughs in reducing malaria morbidity and mortality. Standard in vitro culture environments differ dramatically from in vivo conditions in nutrient levels, hematocrit, and rheology and have lower variability in gas levels and temperature.
Nutritional and physical differences lead to pronounced, and often rapid, changes in phenomenon, important for understanding virulence in Plasmodium. Parasite drug sensitivity may be altered due to culture adaptation selection, supraphysiological metabolite concentrations, and in vitro media formulations. Parasites propagated in vitro, versus in vivo, show altered transcriptomic and genomic patterns related to virulence factors, metabolism, gametocytogenesis, and more.
Direct-from-host methodologies avoid the impacts of in vitro culture adaptation but limit the types of assessments that can be performed as many experiments either require equipment not readily available in endemic settings or necessitate long-term manipulation….
Between traditional remedies and pharmaceutical drugs: prevention and treatment of “Palu” in households in Benin, West Africa
In Benin, malaria clinical cases, including the larger popular entity called “Palu” are evoked when people get fever. “Palu” is often self-diagnosed and self-medicated at home. This study aimed to describe the use of herbal medicine, and/or pharmaceutical medicines for prevention and treatment of malaria at home and the factors associated with this usage.
Methods. A cross-sectional survey was conducted in Benin in an urban and in a rural area in 2016. Around 600 households in each place were selected by using a random sampling of houses GPS coordinates of the families. The association between socio demographic characteristics and the use of herbal medicine was tested by using logistic regression models.
Results. In Cotonou (urban), 43.64% of households reported using herbal or pharmaceutical medicine to prevent “Palu”, while they were 53.1% in Lobogo (rural). To treat “Palu” in Cotonou, 5.34% of households reported using herbal medicine exclusively, 33.70% pharmaceutical medicine exclusively and 60.96% reported using both. In Lobogo, 4% reported using herbal medicine exclusively, 6.78% pharmaceutical medicine exclusively and 89.22% reported using both. In Cotonou, the factors “age of respondent”, “participation to a traditional form of savings” and “low socioeconomic level of the household” were associated with the use of herbal medicine.
Conclusions. This study shows the strong use of herbal medicine to prevent “Palu” or even treat it, and in this case it is mostly associated with the use of pharmaceutical medicine. It also highlights the fact that malaria control and care seeking behaviour with herbal medicine remain closely linked to household low-income status but also to cultural behaviour. The interest of this study is mostly educational, with regards to community practices concerning “Palu”, and to the design of adapted behaviour change communication strategies. Finally, there is a need to take into account the traditional habits of populations in malaria control and define a rational and risk-free use of herbal medicine as WHO-recommended.
Malaria parasite fools body with protein to dodge immune system
By SHIGEKO SEGAWA: OSAKA- The parasite responsible for malaria generates a look-alike of a human protein to suppress the workings of the immune system, leaving humans “defenseless” against infection, according to Japanese and British researchers.
A team comprised mainly of researchers from Osaka University and the University of Oxford said they hope the finding will help lead to new therapies for the mosquito-borne tropical disease.
As plasmodium is resistant to the immune system, the body’s self-defense system, humans can become infected repeatedly. Three years ago, the researchers realized that when plasmodium infects human red blood cells, it generates proteins called RIFINs, which send out signals for suppressing immunity. During the latest study, the researchers analyzed the structure of RIFIN in detail and found it closely resembles part of the structure of a specific human protein, which is involved in the mechanism for preventing the immune system from staging an attack on the body by mistake.
That protein combines with a molecule that suppresses the workings of the immune system. The scientists found the RIFIN that closely imitates the human protein in shape also combines with the same molecule and dodges attacks of the immune system. “We hope our findings will help develop vaccines and therapeutic drugs for malaria,” said Hisashi Arase, a professor of immunology with Osaka University, who is part of the research team. The research results were published in Nature, the British scientific journal.
Why Do Insect Vectors Not Get Ill from the Microbes They Transmit?
Some Evidence from Malaria-carrying Mosquitos by Kevin Noonan. The conservation of diverse and molecularly well-defined hemocyte types between distantly related mosquito genera and the apparent absence of megacytes in our Ae. aegypti mosquito dataset raise questions as to how the immune systems of these mosquito species have evolved to limit their capacity to transmit parasites and arboviruses to humans. This knowledge will ultimately underpin immunological strategies aimed at interrupting disease transmission by rendering mosquitoes resistant to such pathogens.
The conservation of diverse and molecularly well-defined hemocyte types between distantly related mosquito genera and the apparent absence of megacytes in our Ae. aegypti mosquito dataset raise questions as to how the immune systems of these mosquito species have evolved to limit their capacity to transmit parasites and arboviruses to humans. This knowledge will ultimately underpin immunological strategies aimed at interrupting disease transmission by rendering mosquitoes resistant to such pathogens.
Anemia &Dracunculiasis Guinea Worm &Elimination &Leishmaniasis &MDA &Schistosomiasis Bill Brieger | 09 Sep 2020
NTD News Today 2020-09-09 from ASTMH
The current table of contents from the American Journal of Tropical Medicine and Hygiene features several important articles on neglected tropical diseases and malaria. Below are abstracts of several with links to the journal.
Agent-Based Simulation for Seasonal Guinea Worm Disease in Chad Dogs
The campaign to eradicate dracunculiasis (Guinea worm [GW] disease) and its causative pathogen Dracunculus medinensis (GW) in Chad is challenged by infections in domestic dogs, which far outnumber the dwindling number of human infections. We present an agent-based simulation that models transmission of GW between a shared water source and a large population of dogs. The simulation incorporates various potential factors driving the infections including external factors and two currently used interventions, namely, tethering and larvicide water treatments.
By defining and estimating infectivity parameters and seasonality factors, we test the simulation model on scenarios where seasonal patterns of dog infections could be driven by the parasite’s life cycle alone or with environmental factors (e.g., temperature and rainfall) that could also affect human or dog behaviors (e.g., fishing versus farming seasons).
We show that the best-fitting model includes external factors in addition to the pathogen’s life cycle. From the simulation, we estimate that the basic reproductive number, R 0, is approximately 2.0; our results also show that an infected dog can transmit the infection to 3.6 other dogs, on average, during the month of peak infectivity (April). The simulation results shed light on the transmission dynamics of GWs to dogs and lay the groundwork for reducing the number of infections and eventually interrupting transmission of GW.
Village Response to Mass Drug Administration for Schistosomiasis in Mwanza Region, Northwestern Tanzania
Are We Missing Socioeconomic, Cultural, and Political Dimensions?
Praziquantel (PZQ)-based mass drug administration (MDA) is the main approach for controlling schistosomiasis in endemic areas. Interventions such as provision and use of clean and safe water, minimizing contacts with infested water, disposal of human waste in latrines, and snail control provide additional key interventions to break the transmission cycle and could complement and perhaps sustain the benefits of MDA. However, all interventions deployed need to be accepted by the targeted communities. A qualitative study was conducted to examine factors that might differentiate villages which did not show a substantial decrease in Schistosoma mansoni prevalence despite repeated, high treatment coverage referred to as “persistent hotspot villages” from villages which showed a substantial decrease in prevalence referred to as “responding (RES) villages.” A convenient sample of adults was drawn from eight villages. Thirty-nine key informants were interviewed and 16 focus groups were held with a total of 123 participants. Data were analyzed manually using a thematic content approach. In both hotspot and RES villages, schistosomiasis was not considered to be a priority health problem because of its chronic nature, lack of knowledge and awareness, and poverty among study communities.
Hotspot villages exhibited poor leadership style, lack of or insufficient social engagement, little or lack of genuine community participation, little motivation, and commitment to schistosomiasis control compared with RES villages where there were commitment and motivation to fight schistosomiasis. We support the view of scholars who advocate for the adoption of a biosocial approach for effective and sustainable PZQ-based MDA for schistosomiasis control.
Assessment of Incubation Period of Cutaneous Leishmaniasis due to Leishmania major in Tunisia
The period between the infective sandfly bites and appearance of cutaneous leishmaniasis (CL) lesions is still hypothetical and little studied. This work aimed at assessing the incubation time of zoonotic CL (ZCL) due to Leishmania major using a standardized methodology. The retrospective analysis used the epidemiological, clinical, and biological information available in the database recording all the CL cases diagnosed at the Parasitology Department of the Pasteur Institute of Tunis during 2015–2019. It allowed for the selection of 92 privileged observations 1) of confirmed CL cases with presentation suggestive of ZCL form 2) living in northern regions free of ZCL 3) with a single infective trip of less than a week to ZCL foci during transmission season and 4) with accurate dates of travel and onset of lesions. Incubation length computed in this population ranged from 1 to 21 weeks, with a median of 5 weeks (interquartile range: 3–8.5 weeks).
Schistosoma mansoni Vector Snails in Antigua and Montserrat
Snail-Related Considerations Pertinent to a Declaration of Elimination of Human Schistosomiasis.
Investigations leading to a WHO-validated declaration of elimination of schistosomiasis transmission are contemplated for several countries, including Caribbean island nations. With assistance from the Pan American Health Organization, we undertook freshwater snail surveys in two such nations, Antigua and Barbuda, and Montserrat in September and October 2017. Historically, the transmission of Schistosoma mansoni supported by the Neotropical vector snail Biomphalaria glabrata occurred in both countries. Transmission on the islands is thought to have been interrupted by the treatment of infected people, improved sanitation, introduction of competitor snails, and on Montserrat with the eruption of the Soufrière volcano which decimated known B. glabrata habitats. Guided by the available literature and local expertise, we found Biomphalaria snails in seven of 15 and one of 14 localities on Antigua and Montserrat, respectively, most of which were identified anatomically and molecularly as Biomphalaria kuhniana.
Two localities on Antigua harbored B. glabrata, but no schistosome infections in snails were found. For snail-related aspects of validation of elimination, there are needs to undertake basic local training in medical malacology, be guided by historical literature and recent human schistosomiasis surveys, improve and validate sampling protocols for aquatic habitats, enlist local expertise to efficiently find potential transmission sites, use both anatomical and molecular identifications of schistosomes or putative vector snail species found, if possible determine the susceptibility of recovered Biomphalaria spp. to S. mansoni, publish survey results, and provide museum vouchers of collected snails and parasites as part of the historical record.
Decreased Mortality of falciparum Malaria in Anemic Prisoners of War?
Modern clinical trials have suggested that anemia protects against malaria mortality. Military records of the Second World War in Asia were examined to see if there was support for this hypothesis. When relatively well-nourished Imperial Japanese Navy sailors captured on Nauru (n = 799) were imprisoned on the Fauro Islands, 26% died from falciparum malaria. Similarly treated but very malnourished colocated Imperial Army soldiers experienced low stable malaria mortality. One-fifth of previously healthy Australian Army soldiers (n = 252) retreating from New Britain died largely because of malaria in April 1942. Malnourished prisoners of war, who were as a group very anemic, both Australian Army soldiers in Thailand and Japanese Army soldiers in Papua New Guinea, had high malaria rates but very low (< 3%) mortality rates. Malaria immunity does not adequately explain this dichotomy, suggesting that severe nutritional deprivation may be protective against malaria mortality possibly because of iron-deficiency anemia.
Anemia &Integration &Malaria in Pregnancy Bill Brieger | 09 Aug 2008
Anemia: another place to focus on integration within antenatal care
Anemia in pregnancy is responsible not only for threats to a woman’s health, but ultimately the survival of the child. Hotez and Molyneux in a PLoS Neglected Tropical Diseases editorial explain that …
“… most of the 7.5 million pregnant women infected with hookworm likely live in areas of sub-Saharan Africa that place them at risk for malaria. At the same time, malaria control and NTD control have each been shown to reduce anemia both in children and in pregnant women. Therefore, combining malaria and NTD control practices in a unified anemia framework affords one of the best opportunities to reduce the huge burden of morbidity and mortality that results from anemia in sub-Saharan Africa.”
Each disease presents its own challenges. Guyatt and Snow report that, “Although the vast majority of women with malaria infections during pregnancy remain asymptomatic, infection increases the risk of maternal anemia and delivering a low-birth-weight (LBW) baby.” Furthermore, “It is estimated that in areas where malaria is endemic, around 19% of infant LBWs are due to malaria and 6% of infant deaths are due to LBW caused by malaria. These estimates imply that around 100,000 infant deaths each year could be due to LBW caused by malaria during pregnancy in areas of malaria endemicity in Africa.”
Addressing hookworm during pregnancy in Peru, Larocque and colleagues found that pregnant women, “infected with moderate and heavy intensities of hookworm infection and those with moderate and heavy intensities of both hookworm and Trichuris infections were more likely to suffer from anemia than women having no or light intensities. These results support routine anthelminthic treatment within prenatal care programs in highly endemic areas.”
Positive experiences on anthelminthic control were also reported from Nepal in the Lancet. During prenatal care “… women received albendazole twice during pregnancy. Women given albendazole in the second trimester of pregnancy had a lower rate of severe anaemia during the third trimester. Birthweight of infants of women who had received two doses of albendazole rose by 59 g , and infant mortality at 6 months fell by 41%. Antenatal anthelmintics could be effective in reducing maternal anaemia and improving birthweight and infant survival in hookworm-endemic regions.”
We reported from Mozambique that PMTCT and IPTp for malaria in pregnancy control are integrated into antenatal care in many clinics. One can see metronidazole in addition to SP and AZT in the picture among the preventive medicines available for pregnant women. Countries can make their choices of anthelminthics, including albendazole, but the meassage that Hotez and Molyneux convey is the need to control NTDs like soil transmitted helminths should be an integral part of services for pregnant women.