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Background More details about human movement patterns are needed to evaluate relationships between daily travel and malaria risk at finer scales. A multiagent mobility simulation model was built to simulate the movements of villagers between home and their workplaces in 2 townships in Myanmar. Methods An agent-based model (ABM) was built to simulate daily travel to and from work based on responses to a travel survey. Key elements for the ABM were land cover, travel time, travel mode, occupation, malaria prevalence, and a detailed road network. Most visited network segments for different occupations and for malaria-positive cases were extracted and compared. Data from a separate survey were used to validate the simulation. Results Mobility characteristics for different occupation groups showed that while certain patterns were shared among some groups, there were also patterns that were unique to an occupation group. Forest workers were estimated to be the most mobile occupation group, and also had the highest potential malaria exposure associated with their daily travel in Ann Township. In Singu Township, forest workers were not the most mobile group; however, they were estimated to visit regions that had higher prevalence of malaria infection over other occupation groups. Conclusions Using an ABM to simulate daily travel generated mobility patterns for different occupation groups. These spatial patterns varied by occupation. Our simulation identified occupations at a higher risk of being exposed to malaria and where these exposures were more likely to occur. [ABSTRACT FROM AUTHOR]

The global malaria morbidity and mortality witnessed an increase from 2019 to 2020 partly due to disruptions in control programs' activities imposed by the COVID-19 pandemic. Therefore, there is still a significant burden of malaria in Cameroon which needs attention from all fronts to attain elimination goals. It is normally expected that a typical forest ecology that has undergone urbanization and subjected to high rates of ecological instabilities should also have a shift from characteristic perennial malaria transmission and a shift in the type of malaria endemicity plaguing such distorted forest ecology. In this observational comparative study, we randomly enrolled participants from rural and urban settings of a forest zone during a low malaria transmission period, which coincided with the onset of COVID-19 pandemic. An optimized structured questionnaire was employed, to collect socio-demographic data and associated risk factors. The CareStart™ Malaria HRP2 antigen test was performed on participants from both settings to determine the prevalence of community asymptomatic malaria. Of 307 participants, 188 (61.0%) were from the rural, while 119 (38.8%) from the urban community. The overall prevalence of asymptomatic malaria (27.0%) detected Plasmodium falciparum antigen in 83 participants. The urban community's prevalence was 4.2% (5 positives) while the rural community's was 41.5% (78 positives). In simple logistic regression models, rural forest community and farm around the house were statistically significant predictors of testing positive (coefficient 2.8, 95% CI 1.8-3.7, p value<0.001) and (coefficient 3.1, 95% CI 1.1-5.1, p value =0.003), respectively. In the multivariate model, the strongest predictor of testing positive was living in a rural community, with p < 0.001 and odds ratio of 10.9 (95% CI, 3.8-31.8). These results indicate that during a low transmission period, the prevalence of asymptomatic malaria differs between depleted urban and rural forested settings, suggesting a need for strategic target intervention for the control of asymptomatic malaria. [ABSTRACT FROM AUTHOR]

This study investigated the influence of climate factors on malaria incidence in the Sundargarh district, Odisha, India. The WEKA machine learning tool was used with two classifier techniques, Multi-Layer Perceptron (MLP) and J48, with three test options, 10-fold cross-validation, percentile split, and supplied test. A comparative analysis was carried out to ascertain the superior model among malaria prediction accuracy techniques in varying climate contexts. The results suggested that J48 had exhibited better skill than MLP with the 10-fold cross-validation method over the percentile split and supplied test options. J48 demonstrated less error (RMSE = 0.6), better kappa = 0.63, and higher accuracy = 0.71), suggesting it as most suitable model. Seasonal variation of temperature and humidity had a better association with malaria incidents than rainfall, and the performance was better during the monsoon and post-monsoon when the incidents are at the peak. [ABSTRACT FROM AUTHOR]

The existence and multiplication of open dumpsites (ODs) around residential settlements are associated with environmental health outcomes in urbanizing settlements of developing countries. The study assessed existing practice and perceived health hazards of residence around ODs in Nigerian heterogeneous urban settlements. The cross-sectional, mixed-method study administered a validated questionnaire on 195 respondents using a 4-stage sampling technique. Two focus group discussions (FGDs) were conducted and analysed by ATLAS.ti software. Continuous and categorical variables were respectively presented by means and proportions; associations among variables were determined by chi-square and logistic regression at Pα<0.05. Seventy-two per cent of the respondents disposed of solid waste in ODs, despite good knowledge (95%) and a positive attitude (85%) on perceived health-hazards. One-sixth (15%) of respondents were willing to pay for waste collection service and 50% considered burning as an alternative to open dumping. The most and least perceived health outcomes were malaria and breathing difficulties. Improved water sources and skin irritations were significant predictors of sound SWM practices. [ABSTRACT FROM AUTHOR]

Malaria is a parasitic disease that causes morbidity and mortality among pregnant women in Nigeria. It causes gestational anaemia, low birth weight, miscarriages and stillbirths. A study was conducted at Oke-Iyinmi Primary Health Care Facility, Ado-Ekiti, Nigeria to determine the prevalence of malaria parasite infection (MPI) among some pregnant women who attended antenatal between June and August 2021. Blood samples of the participants were screened for malaria parasites. Structured questionnaires were also administered to the participants in order to examine their mosquito avoidance practice. Data were analyzed with SPSS version 20 and probability value of P< 0.05 was regarded as significant. A total number of 241 pregnant women participated in the study. The prevalence of MPI was 51% with plasmodium falciparumas the only malaria parasite observed. No significant difference (P= 0.506) existed on the prevalence of MPI across the age groups. Participants who stayed outdoors at dusk had higher prevalence of MPI than those who remained indoors. But the prevalence of MPI between them showed no significant difference (P = 0.429). The utilization of bed nets among the participants was poor. As the prevalence of MPI was relatively high in this study, controlled interventions are necessary. Such interventions should include chemoprevention, vector control and enlightenment programme. [ABSTRACT FROM AUTHOR]

It has great importance to study the potential effects of climate change on Plasmodium vivax malaria in Greece because the country can be the origin of the spread of vivax malaria to the northern areas. The potential lengths of the transmission seasons of Plasmodium vivax malaria were forecasted for 2041–2060 and 2061–2080 and were combined. The potential ranges were predicted by Climate Envelope Modelling Method. The models show moderate areal increase and altitudinal shift in the malaria-endemic areas in Greece in the future. The length of the transmission season is predicted to increase by 1 to 2 months, mainly in the mid-elevation regions and the Aegean Archipelago. The combined factors also predict the decrease of vivax malaria-free area in Greece. It can be concluded that rather the elongation of the transmission season will lead to an increase of the malaria risk in Greece than the increase in the suitability values. [ABSTRACT FROM AUTHOR]

Malaria remains a major public health problem, causing 435,000 deaths in 2017. The objective of this study was to estimate the prediction ability of vector species associated with the prediction power of environmental and socio-economic factors for malaria risk. Logistic regression was used for malaria risk estimation. A Radial Basis Function model was applied for estimating the predictive ability of Anopheles species, environmental and socio-economic factors. The lowest fever prevalence was found where Anopheles melas was dominant. Anopheles coluzzi and Anopheles gambiae were the dominant species where prevalence of malaria was high. Altitude, country and vector species were the best predictive factors. Anopheles arabiensis, An. coluzzi and An. gambiae were most common in urban areas. This study will improve the prediction of malaria risk in targeted areas. We have observed how important it is to adapt health policies according to the dominant malaria vector in a region. [ABSTRACT FROM AUTHOR]

Background. Malaria is one of the leading causes of morbidity and mortality especially in pregnant women and under-five-year-old children. However, data on the prevalence among delivering mothers, potential fetal transmission, and associated birth outcomes is lacking in Ethiopia. Objective. To assess the prevalence of Plasmodium infection from peripheral, placental, and cord blood samples among delivering mothers in Kuch health center, Northwest Ethiopia. Methods. An institution-based cross-sectional study was conducted among 218 delivering mothers from February to May 2021 in Kuch health center. Data on sociodemographic characteristics and clinical and obstetric history of mothers were collected using a structured questionnaire. Giemsa stained blood films from maternal capillary and placental and umbilical cord blood were examined for plasmodium infection. Data were analyzed using Statistical Package for the Social Sciences version 23 software package. Results. The prevalence of maternal, placental, and umbilical cord malaria was 6.4% (14/218), 2.3% (5/218), and 0.5% (1/218), respectively. Plasmodium falciparum and Plasmodium vivax accounted 3.7% (8/218) and 2.8% (6/218), respectively, in maternal peripheral blood but only Plasmodium falciparum was detected in placental and umbilical cord blood samples. Maternal malaria had significant association with primigravida ( χ 2 = 12.611 , p = 0.002) and low birth weight ( χ 2 = 8.381 , p = 0.004). Placental malaria was also significantly associated with low birth weight ( χ 2 = 32.255 , p ≤ 0.001). Conclusion. The prevalence of malaria among delivering mothers was considerable. Maternal peripheral malaria had a significant association with gravidity and birth weight. Placental and umbilical cord malaria also had a significant association with birth weight. Pregnant mothers should be examined for malaria and receive appropriate treatment to prevent adverse birth outcomes. [ABSTRACT FROM AUTHOR]

In a cross-sectional molecular study in the Democratic Republic of the Congo, 78% of households had ≥1 member infected with Plasmodium falciparum, Plasmodium vivax, and/or Plasmodium ovale spp.; 47% of children and 33% of adults tested positive for ≥1 species. Risk factors varied by species and age group. [ABSTRACT FROM AUTHOR]

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Introduction: Malaria is one of the major life-threatening health problems in most of the tropical countries. Children are the most vulnerable group accounting for 67% of all malaria-associated deaths worldwide. Southern Haryana is typically endemic for malaria. Therefore, the present study was undertaken to describe the clinical presentation of complicated malaria and correlate clinical complications with malarial species. Materials and Methods: It was an observational cross-sectional study conducted in the Department of Microbiology along with Department of Pediatrics, Shaheed Hasan Khan Mewati Government Medical College, Nalhar, Nuh, Haryana. A total of 100 children with severe malaria admitted in the pediatric ward, confirmed by peripheral blood smear and rapid diagnostic test, were included. Results: Out of 100 cases admitted, majority were due to Plasmodium vivax (73%), followed by mixed (18%) and Plasmodium falciparum (9%) infection. Children below 5 years were more infected (57%). Male preponderance was seen (55%). Fever was the most common symptom observed (95%). Pallor was the most common sign observed (85%). Among severity parameters, the most common were severe anemia (41%), jaundice (17%), abnormal bleeding (17%), convulsions (15%), and acute respiratory distress syndrome (7%). The case fatality rate was 3%. Conclusion: P. vivax was previously known to cause benign malaria. The present study found that P. vivax mono-infection can cause severe malaria in children and should no longer be considered as benign malaria. [ABSTRACT FROM AUTHOR]

This study in Burkina Faso investigated whether offspring of young mothers who had received weekly periconceptional iron supplementation in a randomised controlled trial were at increased risk of malaria. A child safety survey was undertaken in the peak month of malaria transmission towards the end of the trial to assess child iron biomarkers, nutritional status, anaemia and malaria outcomes. Antenatal iron biomarkers, preterm birth, fetal growth restriction and placental pathology for malaria and chorioamnionitis were assessed. Data were available for 180 babies surviving to the time of the survey when their median age was 9 months. Prevalence of maternal iron deficiency in the last trimester based on low body iron stores was 16%. Prevalence of active placental malaria infection was 24.8%, past infection 59% and chorioamnionitis 55.6%. Babies of iron supplemented women had lower median gestational age. Four out of five children ≥ 6 months were iron deficient, and 98% were anaemic. At 4 months malaria prevalence was 45%. Child iron biomarkers, anaemia and malaria outcomes did not differ by trial arm. Factors associated with childhood parasitaemia were third trimester C‐reactive protein level (OR 2.1; 95% CI 1.1–3.9), active placental malaria (OR 5.8; 1.0–32.5, P = 0.042) and child body iron stores (OR 1.13; 1.04–1.23, P = 0.002). Chorioamnionitis was associated with reduced risk of child parasitaemia (OR 0.4; 0.1–1.0, P = 0.038). Periconceptional iron supplementation of young women did not alter body iron stores of their children. Higher child body iron stores and placental malaria increased risk of childhood parasitaemia. [ABSTRACT FROM AUTHOR]

Background: Malaria is still one of the public health problems that can cause death primarily in high-risk groups. High incidence of malaria caused by unhealthy environment and patterns of Society behavior. Objectives: Assessing the relationship between environmental factors and the society behavior factors with malaria incidence. Method: This is a case-control study. Samples were taken using sampling purposive with criteria: Age 7-50 years and case groups were noted as clinical malaria patients. Data is collected by observing and filling out questionnaires. Risk factors are analyzed using the Chi-Square test, knowing the risks with the odds ratio. The dominant risk factors were analyzed using binary logistic regression. Results: The variable associated with the malaria incident is ventilation (0,000), 2.5 (1.6-4.1), ceiling (0,015), 1.7 (1.1-2.7), puddles around the house (0,005), 1.9 (1.2-3.0), using of mosquito nets (0,000), 4.1 (2.4-6.4) and using mosquito repellent (0.001), 2,2 (1,4-3,5). Conclusion: The proven environmental factors associated with malaria incidents are ventilation, ceilings, and puddles around the house. The Society behavior factor associated with malaria incidents is using mosquito nets and using mosquito repellent. Proves that the use of mosquito nets is a major risk factor for malaria incidents, with a risk of 4.3 times greater in those who when sleeping at night do not use mosquito nets. [ABSTRACT FROM AUTHOR]

Pregnant women and children are the most vulnerable populations for malaria infection. Yet, knowledge of risk, and preventive measures are poor among this population. Using the 2015 Nigeria Malaria Indicator Survey, we applied logit link function to estimate the associations of wealth status, educational attainment, and region of residence with malaria risk knowledge and prevention strategies (using a treated mosquito net and malaria drugs) among 739 Nigerian pregnant women aged 15–49 years. Urban women who had obtained a secondary school education (Adjusted odds ratio [aOR] = 2.12; 95% confidence interval [CI] 1.09–4) or higher (aOR = 8.31; 95% CI 3.2–22) had more knowledge of malaria risk. Urban women in the South-West (aOR = 5.02; [CI] 2.02–12.50) and South-East (aOR = 2.68; 95% CI 1.19–6.06) were more likely to use treated mosquito nets during pregnancy. Women in the urban South-West (aOR = 4.04; 95% CI 1.5–11) were more likely to use malaria drugs during pregnancy than those in the North-Central. A wide regional disparity in the knowledge of malaria risks and use of preventive measures exists. Thus, promoting equal access to malaria preventive measures as well as improving knowledge about malaria transmission by mosquitoes should be considered as essential components of ongoing malaria control and elimination efforts in Nigeria. [ABSTRACT FROM AUTHOR]

Background: Preterm birth (PTB) can be caused by different factors. The factors can be classified into different categories: socio demographic, obstetric, reproductive health, medical, behavioral and nutritional related. The objective of this review was identifying determinants of PTB among mothers who gave birth in East African countries. Methods: We have searched the following electronic bibliographic databases: PubMed, Google scholar, Cochrane library, AJOL (African journal online). Cross sectional, case control and cohort study published in English were included. There was no restriction on publication period. Studies with no abstracts and or full texts, editorials, and qualitative in design were excluded. Funnel plot was used to check publication bias. I-squared statistic was used to check heterogeneity. Pooled analysis was done by using fixed and random effect model. The Joanna Briggs Critical Appraisal Tools for review and meta-analysis was used to check the study quality. Results: A total of 58 studies with 134,801 participants were used to identify determinants of PTB. On pooled analysis, PTB was associated with age < 20 years (AOR 1.76, 95% CI: 1.33–2.32), birth interval less than 24 months (AOR 2.03, 95% CI 1.57–2.62), multiple pregnancy (AOR 3.44,95% CI: 3.02–3.91), < 4 antenatal care (ANC) visits (AOR 5.52, 95% CI: 4.32–7.05), and absence of ANC (AOR 5.77, 95% CI: 4.27–7.79). Other determinants of PTB included: Antepartum hemorrhage (APH) (AOR 4.90, 95% CI: 3.48–6.89), pregnancy induced hypertension (PIH) (AOR 3.10, 95% CI: 2.34–4.09), premature rupture of membrane (PROM) (AOR 5.90, 95% CI: 4.39–7.93), history of PTB (AOR 3.45, 95% CI: 2.72–4.38), and history of still birth/abortion (AOR 3.93, 95% CI: 2.70–5.70). Furthermore, Anemia (AOR 4.58, 95% CI: 2.63–7.96), HIV infection (AOR 2.59, 95% CI: 1.84–3.66), urinary tract infection (UTI) (AOR 5.27, 95% CI: 2.98–9.31), presence of vaginal discharge (AOR 5.33, 95% CI: 3.19–8.92), and malaria (AOR 3.08, 95% CI: 2.32–4.10) were significantly associated with PTB. Conclusions: There are many determinants of PTB in East Africa. This review could provide policy makers, clinicians, and program officers to design intervention on preventing occurrence of PTB. [ABSTRACT FROM AUTHOR]

Background: Malaria can cause pain and death. Malaria occurs in 91 countries in the world and 50% of the population lives in areas at risk of contracting malaria with a morbidity rate of 216 million cases and death of 445,000 people. The purpose of this research was to analyze the risk factors for malaria incidence in Asahan Regency. Materials and Methods: This type of research is observational analytic, using matched case-control according to gender and age. The population was all patients and not malaria sufferers who live in Asahan Regency in 2017. Malaria sufferers were recorded at E-socialism Public Health Center as many as 469 cases. Case samples were malaria patients recorded in E-Sismal Public Health Center, taken by simple random sampling as many as 90 cases, control samples are residents who live near the case house and non-malaria sufferers are not recorded in E-Sismal Public Health Center as many as 90 people. Data obtained through observation and interviews with questionnaires. Bivariate analysis using Mc.Neymar, multivariate use Conditional logistic regression. Result: The results found that there was a correlation of the presence of livestock, the habit of the night out and hanging clothes with the incidence of malaria. The most influential risk factor for malaria incidence is night out habits (OR = 5,086, 95% CI 2,675 - 9,668). Conclusion: It is recommended to increase public knowledge by conducting counseling about malaria prevention efforts by actively participating in efforts to protect themselves from mosquito bites if they do activities outside the house at night or by reducing activities outside the home at night. [ABSTRACT FROM AUTHOR]

Background Plasmodium knowlesi causes severe and fatal malaria, and incidence in Southeast Asia is increasing. Factors associated with death are not clearly defined. Methods All malaria deaths in Sabah, Malaysia, from 2015 to 2017 were identified from mandatory reporting to the Sabah Department of Health. Case notes were reviewed, and a systematic review of these and all previously reported fatal P. knowlesi cases was conducted. Case fatality rates (CFRs) during 2010–2017 were calculated using incidence data from the Sabah Department of Health. Results Six malaria deaths occurred in Sabah during 2015–2017, all from P. knowlesi. Median age was 40 (range, 23–58) years; 4 cases (67%) were male. Three (50%) had significant cardiovascular comorbidities and 1 was pregnant. Delays in administering appropriate therapy contributed to 3 (50%) deaths. An additional 26 fatal cases were included in the systematic review. Among all 32 cases, 18 (56%) were male; median age was 56 (range, 23–84) years. Cardiovascular-metabolic disease, microscopic misdiagnosis, and delay in commencing intravenous treatment were identified in 11 of 32 (34%), 26 of 29 (90%), and 11 of 31 (36%) cases, respectively. The overall CFR during 2010–2017 was 2.5/1000: 6.0/1000 for women and 1.7/1000 for men (P =.01). Independent risk factors for death included female sex (odds ratio, 2.6; P =.04), and age ≥45 years (odds ratio, 4.7; P <.01). Conclusions Earlier presentation, more rapid diagnosis, and administration of intravenous artesunate may avoid fatal outcomes, particularly in females, older adults, and patients with cardiovascular comorbidities. [ABSTRACT FROM AUTHOR]

Gene drive technology has immense potential. The ability to bypass the laws of Mendelian inheritance and almost ensure the transmission of specific genetic material to future generations creates boundless possibilities. But alongside these boundless possibilities are major social and ethical issues. This article aims to introduce gene drive technology, some of its potential applications, and some of the social and ethical issues that arise during research into the technology. For example, is investigation into gene drives hubristic? Would applications of gene drives count as technological fixes? Or does research into such a technology sit on a slippery slope or lock us in to its full‐scale use? Are there perverse effects of engaging in research, and, most importantly, who ought to be included in the decision‐making process regarding research and field trials? Understanding the basic ethical landscape of this technology will prove invaluable to the public, scientists, and policy‐makers as research moves forward. [ABSTRACT FROM AUTHOR]

Background The United Kingdom documented a decline of >30% in imported cases of malaria annually between 1996 and 2003; however, there are still approximately 1700 cases and 5–10 deaths each year. Prophylaxis health messages focus on families returning to their country of origin. Methods We reviewed 225 records of patients seen in Cambridge University Hospital Foundation Trust [CUHFT], a tertiary referral center in Cambridge, England. All records of patients seen in CUHFT between 2002–2016 were analyzed in the context of national figures from Public Health England. Results Between 2004–2016, there was no decrease in imported cases of malaria locally or nationally. Plasmodium falciparum remains responsible for most imported infections (66.7%); Plasmodium vivax contributed 15.1%, Plasmodium malariae 4%, and Plasmodium ovale 6.7%; 7.5% (17/225) of patients had an incomplete record. Most cases were reported in people coming from West Africa. Sierra Leone and the Ivory Coast had the highest proportions of travelers being infected at 8 and 7 per 1000, respectively. Visiting family in the country of origin (27.8%) was the commonest reason for travel. However, this was exceeded by the combined numbers traveling for business and holidays (22.5% and 20.1%, respectively). Sixty percent of patients took no prophylaxis. Of those who did, none of the patients finished their chemoprophylaxis regimen. Conclusions Significant numbers of travelers to malarious countries still take no chemoprophylaxis. Health advice about prophylaxis before travel should be targeted not only at those visiting family in their country of origin but also to those traveling for holiday and work. [ABSTRACT FROM AUTHOR]

Background The effect of timing of exposure to first Plasmodium falciparum infections during early childhood on the induction of innate and adaptive cytokine responses and their contribution to the development of clinical malaria immunity is not well established. Methods As part of a double-blind, randomized, placebo-controlled trial in Mozambique using monthly chemoprophylaxis with sulfadoxine-pyrimethamine plus artesunate to selectively control timing of malaria exposure during infancy, peripheral blood mononuclear cells collected from participants at age 2.5, 5.5, 10.5, 15, and 24 months were stimulated ex vivo with parasite schizont and erythrocyte lysates. Cytokine messenger RNA expressed in cell pellets and proteins secreted in supernatants were quantified by reverse-transcription quantitative polymerase chain reaction and multiplex flow cytometry, respectively. Children were followed up for clinical malaria from birth until 4 years of age. Results Higher proinflammatory (interleukin [IL] 1, IL-6, tumor necrosis factor) and regulatory (IL-10) cytokine concentrations during the second year of life were associated with reduced incidence of clinical malaria up to 4 years of age, adjusting by chemoprophylaxis and prior malaria exposure. Significantly lower concentrations of antigen-specific T-helper 1 (IL-2, IL-12, interferon-γ) and T-helper 2 (IL-4, IL-5) cytokines by 2 years of age were measured in children undergoing chemoprophylaxis compared to children receiving placebo (P <.03). Conclusions Selective chemoprophylaxis altering early natural exposure to malaria blood stage antigens during infancy had a significant effect on T-helper lymphocyte cytokine production >1 year later. Importantly, a balanced proinflammatory and anti-inflammatory cytokine signature, probably by innate cells, around age 2 years was associated with protective clinical immunity during childhood. Clinical Trials Registration NCT00231452. [ABSTRACT FROM AUTHOR]

Background. Socioeconomic factors influence the prevalence of malaria infection in endemic areas. This study evaluated the socioeconomic risk factors for Plasmodium falciparum infection in primary school children in the Volta region of Ghana. Methods. This cross-sectional study involved selected primary school children from the region; questionnaires were administered, and blood samples were collected for malaria detection using a rapid diagnostic test (RDT) and microscopy. Results. A total of 550 primary school children were enrolled in this study. The predominant occupation of the parents was trading (mothers, 334, 60.73%; fathers, 254, 46.18%) and farming (mothers, 156, 28.36%; fathers, 170, 30.91%). Three hundred and five (305; 55.45%) children tested positive for malaria with RDT and microscopy. Male sex (AOR=1.53), rural area (Afegame school) (AOR=4.01) and parental farming occupation (AOR=6.39), were independently associated with P. falciparum infection. Conclusions. Plasmodium falciparum infection was significantly found in children in rural areas of Ghana with low socioeconomic status in this study. [ABSTRACT FROM AUTHOR]

Background Mass drug administration (MDA) may further reduce malaria transmission in low-transmission areas. The impact of MDA on the dynamics of malaria transmission was determined in a prospective cohort study. Methods Annual rounds of MDA with dihydroartemisinin-piperaquine (DP) were implemented were implemented in 2014 and 2015 in six village pairs before the malaria transmission season. Blood samples were collected from residents between July and December for microscopy and nested PCR. Incidence and prevalence of infection, clinical disease, and risk of malaria reinfection post-MDA were determined. Results Coverage of three DP doses was 68.2% (2014) and 65.6% (2015), compliance was greater than 80%. Incidence of infection was significantly lower in 2014 (incidence rate [IR] = 0.2 per person year [PPY]) than in 2013 (IR = 1.1 PPY; P <.01); monthly infection prevalence declined in the first three months post-MDA. Clinical malaria incidence was lower in 2014 (IR = 0.1 PPY) and 2015 (IR = 0.2 PPY) than in 2013 (IR = 0.4 PPY; P <.01), but remained higher in eastern Gambia. Individuals infected before MDA had a 2-fold higher odds of reinfection post-MDA (adjusted odds ratio = 2.5, 95% confidence interval 1.5–4.3; P <.01). Conclusions MDA reduced malaria infection and clinical disease during the first months. The reduction was maintained in low-transmission areas, but not in eastern Gambia. Annual MDA could be followed by focal MDA targeting individuals infected during the dry season. Repeated MDA rounds, some during the dry season over larger geographical areas, may result in a more marked and sustained decrease of malaria transmission. [ABSTRACT FROM AUTHOR]

Background It remains unclear whether improving iron status increases malaria risk, and few studies have looked at the effect of host iron status on subsequent malaria infection. We therefore aimed to determine whether a child's iron status influences their subsequent risk of malaria infection in sub-Saharan Africa. Methods We assayed iron and inflammatory biomarkers from community-based cohorts of 1309 Kenyan and 1374 Ugandan children aged 0–7 years and conducted prospective surveillance for episodes of malaria. Poisson regression models were fitted to determine the effect of iron status on the incidence rate ratio (IRR) of malaria using longitudinal data covering a period of 6 months. Models were adjusted for age, sex, parasitemia, inflammation, and study site. Results At baseline, the prevalence of iron deficiency (ID) was 36.9% and 34.6% in Kenyan and Ugandan children, respectively. ID anemia (IDA) affected 23.6% of Kenyan and 17.6% of Ugandan children. Malaria risk was lower in children with ID (IRR, 0.7; 95% confidence interval [CI], 0.6, 0.8; P <.001) and IDA (IRR, 0.7; 95% CI, 0.6, 0.9; P =.006). Low transferrin saturation (<10%) was similarly associated with lower malaria risk (IRR, 0.8; 95% CI, 0.6, 0.9; P =.016). However, variation in hepcidin, soluble transferrin receptors (sTfR), and hemoglobin/anemia was not associated with altered malaria risk. Conclusions ID appears to protect against malaria infection in African children when defined using ferritin and transferrin saturation, but not when defined by hepcidin, sTfR, or hemoglobin. Additional research is required to determine causality. Clinical Trials Registration ISRCTN32849447 [ABSTRACT FROM AUTHOR]

Background In holoendemic areas, children suffer the most from Plasmodium falciparum malaria, yet newborns and young infants express a relative resistance to both infection and severe malarial disease (SM). This relative resistance has been ascribed to maternally-derived anti-parasite immunoglobulin G; however, the targets of these protective antibodies remain elusive. Methods We enrolled 647 newborns at birth from a malaria-holoendemic region of Tanzania. We collected cord blood, measured antibodies to Plasmodium falciparum Schizont Egress Antigen-1 (PfSEA-1), and related these antibodies to the risk of severe malaria in the first year of life. In addition, we vaccinated female mice with PbSEA-1, mated them, and challenged their pups with P. berghei ANKA parasites to assess the impact of maternal PbSEA-1 vaccination on newborns' resistance to malaria. Results Children with high cord-blood anti–PfSEA-1 antibody levels had 51.4% fewer cases of SM compared to individuals with lower anti–PfSEA-1 levels over 12 months of follow-up (P =.03). In 3 trials, pups born to PbSEA-1–vaccinated dams had significantly lower parasitemia and longer survival following a P. berghei challenge compared to pups born to control dams. Conclusions We demonstrate that maternally-derived, cord-blood anti–PfSEA-1 antibodies predict decreased risk of SM in infants and vaccination of mice with PbSEA-1 prior to pregnancy protects their offspring from lethal P. berghei challenge. These results identify, for the first time, a parasite-specific target of maternal antibodies that protect infants from SM and suggest that vaccination of pregnant women with PfSEA-1 may afford a survival advantage to their offspring. [ABSTRACT FROM AUTHOR]

Introduction: Public health issues and spread of diseases have a direct relationship with the regional geography. The present study was designed and conducted to determine spatial distribution of the incidence of malaria in the city of Jahrom, using Geographical Information System (GIS). Materials and Methods: In the present descriptive study, the geographical longitude and latitude of each patient's place of residence was determined using Moran's spatial self-correlation method, and the disease incidence spots and risk using Kringing's interpolation technique and Jeefoo et al. classification in GIS-10.3. Results: A total of 136 cases occurred over the study years, with the highest Annual Parasitic Incidence (API) in 2008, 2006 and 2007 (0.116, 0.115, and 0.108 per population of 1000 respectively) and since 2008, API has had a slightly fluctuating descending trend. The spatial analysis, Kringing interpolation and Jeefoo classification showed that Jahrom's suburbs have had a very high risk of incidence (0.275 per population of 1000), and Moran's spatial self-correlation showed that the disease was randomly distributed (Moran Index=0.04) (P=0.73) (Z-score=0.33). Conclusion: The incidence of malaria was found to be higher in Jahrom's suburbs than other regions, and spatial analysis showed that high risk regions can provide a useful malaria prevention and control planning tool. [ABSTRACT FROM AUTHOR]

Background We investigated whether adding community scheduled malaria screening and treatment (CSST) with artemether-lumefantrine by community health workers (CHWs) to standard intermittent preventive treatment in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) would improve maternal and infant health. Methods In this 2-arm cluster-randomized, controlled trial, villages in Burkina Faso, The Gambia, and Benin were randomized to receive CSST plus IPTp-SP or IPTp-SP alone. CHWs in the intervention arm performed monthly CSST during pregnancy. At each contact, filter paper and blood slides were collected, and at delivery, a placental biopsy was collected. Primary and secondary endpoints were the prevalence of placental malaria, maternal anemia, maternal peripheral infection, low birth weight, antenatal clinic (ANC) attendance, and IPTp-SP coverage. Results Malaria infection was detected at least once for 3.8% women in The Gambia, 16.9% in Benin, and 31.6% in Burkina Faso. There was no difference between study arms in terms of placenta malaria after adjusting for birth season, parity, and IPTp-SP doses (adjusted odds ratio, 1.06 [95% confidence interval,.78–1.44]; P =.72). No difference between the study arms was found for peripheral maternal infection, anemia, and adverse pregnancy outcomes. ANC attendance was significantly higher in the intervention arm in Burkina Faso but not in The Gambia and Benin. Increasing number of IPTp-SP doses was associated with a significantly lower risk of placenta malaria, anemia at delivery, and low birth weight. Conclusions Adding CSST to existing IPTp-SP strategies did not reduce malaria in pregnancy. Increasing the number of IPTp-SP doses given during pregnancy is a priority. Clinical Trials Registration NCT01941264; ISRCTN37259296. [ABSTRACT FROM AUTHOR]

Background Human movement can undermine malaria control efforts. However, understanding of the association between travel and malaria infection in Africa is limited. We evaluated the association between recent overnight travel and malaria incidence in Uganda. Methods All children aged 0.5–10 years and 1 adult living in 266 randomly selected households within 3 different regions of Uganda were followed up prospectively. Information on overnight travel was collected in 2015–2016. Malaria, defined as fever with parasites detected by microscopy, was measured using passive surveillance. Results At least 1 overnight trip was reported by 64 of 275 (23.3%) participants in Walukuba, 37 of 317 (11.7%) in Nagongera, and 19 of 314 (6.1%) in Kihihi. Among individuals who traveled, the incidence of malaria was higher in the first 60 days after traveling, compared with periods without recent travel at all 3 sites (overall, 1.15 vs 0.33 episodes per person-year; incidence rate ratio, 3.53; 95% confidence interval, 1.85–6.73; P <.001). Risk factors for malaria within 60 days after overnight travel included young age (19.5% in children vs 4.9% in adults; odds ratio, 5.29; 95% confidence interval, 1.34–21.0; P =.02) and not using an insecticide-treated net during travel (18.0% for no use vs 4.1% for any use; 5.10; 1.07–24.5; P =.04). Conclusions Recent overnight travel was associated with a higher incidence of malaria. Individuals who travel may represent a high-risk group that could be targeted for malaria control interventions, particularly use of insecticide-treated nets. [ABSTRACT FROM AUTHOR]

Background Asymptomatic Plasmodium falciparum infections are common in Malawi; however, the implications of these infections for the burden of malaria illness are unknown. Whether asymptomatic infections eventually progress to malaria illness, persist without causing symptoms, or clear spontaneously remains undetermined. We identified asymptomatic infections and evaluated the associations between persistent asymptomatic infections and malaria illness. Methods Children and adults (N = 120) who presented at a health facility with uncomplicated malaria were followed monthly for 2 years. During follow-up visits, participants with malaria symptoms were tested and, if positive, treated. Samples from all visits were tested for parasites using both microscopy and polymerase chain reaction, and all malaria infections underwent genotyping. Cox frailty models were used to estimate the temporal association between asymptomatic infections and malaria illness episodes. Mixed models were used to estimate the odds of clinical symptoms associated with new versus persistent infections. Results Participants had a median follow-up time of 720 days. Asymptomatic infections were detected during 23% of visits. Persistent asymptomatic infections were associated with decreased risk of malaria illness in all ages (hazard ratio 0.50, P <.001). When asymptomatic infections preceded malaria illness, newly-acquired infections were detected at 92% of subsequent clinical episodes, independent of presence of persistent infections. Malaria illness among children was more likely due to newly-acquired infections (odds ratio, 1.4; 95% confidence interval, 1.3–1.5) than to persistent infections. Conclusions Asymptomatic P. falciparum infections are associated with decreased incidence of malaria illness, but do not protect against disease when new infection occurs. [ABSTRACT FROM AUTHOR]

Background Splenectomy increases the risk of severe and fatal infections; however, the risk of Plasmodium vivax malaria is unknown. We quantified the Plasmodium species-specific risks of malaria and other outcomes following splenectomy in patients attending a hospital in Papua, Indonesia. Methods Records of all patients attending Mitra-Masyarakat Hospital 2004–2013 were reviewed, identifying those who underwent splenectomy. Subsequent risks of specific clinical outcomes within 12 months for splenectomized patients were compared to nonsplenectomized patients from their first recorded hospital admission. In addition, patients splenectomized for trauma 2015–2016 were followed prospectively for 14 months. Results Of the 10774 patients hospitalized during 2004–2013, 67 underwent splenectomy. Compared to nonsplenectomized inpatients, patients undergoing splenectomy had a 5-fold higher rate of malaria presentation within 12 months (adjusted hazard ratio [AHR] = 5.0 [95% confidence interval (CI): 3.4–7.3], P <.001). The AHR was 7.8 (95% CI: 5.0–12.3) for P. vivax and 3.0 (95% CI: 1.7–5.4) for P. falciparum (both P <.001). Splenectomized patients had greater risk of being hospitalized for any cause (AHR = 1.8 [95% CI: 1.0–3.0], P =.037) and diarrheal (AHR = 3.5 [95% CI: 1.3–9.6], P =.016). In the 14-month prospective cohort, 12 episodes of P. vivax and 6 episodes of P. falciparum were observed in 11 splenectomised patients. Conclusions Splenectomy is associated with a high risk of malaria, greater for P. vivax than P. falciparum. Eradication of P. vivax hypnozoites using primaquine (radical cure) and subsequent malaria prophylaxis is warranted following splenectomy in malaria-endemic areas. [ABSTRACT FROM AUTHOR]

Background Pregnant women are more susceptible to Plasmodium falciparum than before pregnancy, and infection has consequences for both mother and offspring. The World Health Organization recommends that pregnant woman in areas of transmission receive intermittent preventive treatment (IPTp) starting in the second trimester. Consequently, women are not protected during the first trimester, although P. falciparum infections are both frequent and harmful. Methods A cohort of nulligravid women was followed up during subsequent pregnancy. Malaria was diagnosed by means of microscopy and polymerase chain reaction. Parasites were genotyped at polymorphic loci. Results Among 275 nulligravidae enrolled, 68 women became pregnant and were followed up during pregnancy. Before pregnancy, P. falciparum prevalence rates were 15% by microscopy and 66% by polymerase chain reaction. Microscopic infection rates increased to 29% until IPTp administration, and their density increased by 20-fold. Conversely, submicroscopic infection rates decreased. After IPTp administration, all types of infections decreased, but they increased again late in pregnancy. The risk of infection during pregnancy was higher in women with a microscopic (odds ratio, 6.5; P =.047) or submicroscopic (3.06; P =.05) infection before pregnancy and was not related to the season of occurrence. Most infections during pregnancy were persistent infections acquired before pregnancy. Conclusions Microscopic and submicroscopic malaria infections were frequent in nulligravid women from south Benin. During the first trimester of pregnancy, microscopic infections were more frequent, with a higher parasite density, and mainly derived from parasites infecting the woman before conception. Preventive strategies targeting nonpregnant women with a desire for conception need to be designed. [ABSTRACT FROM AUTHOR]

Abstract Malaria caused by an infection of Plasmodium knowlesi can result in high parasitemia and deaths. Therefore, effective and prompt treatment is necessary to reduce morbidity and mortality. The study aims to characterize P. knowlesi dihydrofolate reductase-thymidylate synthase enzyme (Pk DHFR-TS) and its sensitivity to antifolates. The putative Pkdhfr gene was PCR amplified from field isolates collected from the Southern Thailand. Molecular analysis showed 11 polymorphisms in the dhfr domain of the bifunctional dhfr-ts gene. Of these, 1 polymorphism was a non-synonymous substitution (R34L) that had previously been reported but not associated with antifolate resistance. The recombinant Pk DHFR-TS enzyme was found to be sensitive to standard antifolates—pyrimethamine and cycloguanil—as well as P218, a registered candidate drug currently first in human clinical trial. Results suggest that antifolates class of compounds should be effective against P. knowlesi infection. Graphical abstract Unlabelled Image Highlights • Pk DHFR-TS is a catalytically efficient enzyme compared with that of other non-falciparum enzyme. • Its efficiency may contribute to high replication rate and high parasitemia. • Pk DHFR-TS enzyme is sensitive to conventional and clinical trial antifolates. [ABSTRACT FROM AUTHOR]

Abstract Malaria morbidity and mortality have decreased gradually in the Greater Mekong Subregion (GMS). Presently, WHO sets a goal to eliminate malaria by 2030 in the GMS. However, drug-resistant malaria has been reported from several endemic areas. To achieve the goal of elimination, the status of the emergence and spread of drug resistance should be monitored. In this study, the genotype of the Plasmodium falciparum chloroquine (CQ) resistance transporter gene (pfcrt) and 6 microsatellite DNA loci flanking the gene were examined. P. falciparum isolates (n = 136) was collected from malaria patients in Thailand (n = 50, 2002–2005), Vietnam (n = 39, 2004), Laos (n = 15, 2007) and Cambodia (n = 32, 2009). Amino acid sequences at codons 72–76 on the gene were determined. All of the isolates from Thailand were CQ-resistant (CVIET), as were all of the isolates from Cambodia (CVIET, CVIDT). Thirteen of the 15 isolates (87%) from Laos were CQ-resistant (CVIET, CVIDT), whereas the other 2 (13%) were CQ-susceptible (CVMNK). In contrast, 27 of the 39 isolates (69%) from Vietnam were CQ-susceptible (CVMNK), whereas the other 12 (31%) were CQ-resistant (CVIET, CVIDT, CVMDT) or mixed (CVMNK/CVIDT). The mean of expected heterozygosity of the microsatellite loci was 0.444 in the Thai population, 0.482 in the Cambodian population, and 0.734 in the Vietnamese population. Genetic diversity in the Thai population was significantly lower than that in the Vietnamese population. These results suggested that chloroquine selective pressure on P. falciparum populations is heterogeneous in the GMS. Therefore, further examination to understand the mechanisms behind the emergence and spread of drug-resistant malaria are needed. [ABSTRACT FROM AUTHOR]

The article focuses on the risk factors and risk groups of malaria imported into the Great Britain. It mentions the incidence of malaria among peacekeepers is significantly lower than among the Congolese population. It also mentions the epidemic of malaria among peacekeepers has its own unique characteristics compared with the local population.

Background Mass screening and treatment (MST) aims to reduce malaria risk in communities by identifying and treating infected persons without regard to illness. Methods A cluster-randomized trial evaluated malaria incidence with and without MST. Clusters were randomized to 3, 2, or no MST interventions: MST3, 6 clusters (156 households/670 individuals); MST2, 5 clusters (89 households/423 individuals); and MST0, 5 clusters (174 households/777 individuals). All clusters completed the study with 14 residents withdrawing. In a cohort of 324 schoolchildren (MST3, n = 124; MST2, n = 57; MST0, n = 143) negative by microscopy at enrollment, we evaluated the incidence density of malaria during 3 months of MST and 3 months following. The MST intervention involved community-wide expert malaria microscopic screening and standard therapy with dihydroartemisinin-piperaquine and primaquine for glucose-6 phosphate dehydrogenase–normal subjects. All blood examinations included polymerase chain reaction assays, which did not guide on-site treatment. Results The risk ratios for incidence density of microscopically patent malaria in MST3 or MST2 relative to that in MST0 clusters were 1.00 (95% confidence interval [CI],.53–1.91) and 1.22 (95% CI,.42–3.55), respectively. Similar results were obtained with molecular analysis and species-specific (P. falciparum and P. vivax) infections. Microscopically subpatent, untreated infections accounted for 72% of those infected. Conclusions Two or 3 rounds of MST within 3 months did not impact the force of anopheline mosquito-borne infection in these communities. The high rate of untreated microscopically subpatent infections likely explains the observed poor impact. Clinical Trials Registration NCT01878357. [ABSTRACT FROM AUTHOR]

Objective: To map at a fine spatial scale, the risk of malaria incidence for the important endemic region is Urabá-Bajo Cauca and Alto Sinú, NW Colombia, using a new modelling framework based on GIS and remotely sensed environmental data.Methods: The association between environmental and topographic variables obtained from remote sensors and the annual parasite incidence (API) for the years 2013-2015 was calculated using multiple regression analysis; subsequently, a model was constructed to estimate the API and to project it to the entire endemic region in order to design the risk map. The model was validated by relating the obtained API values with the presence of the three main Colombian malaria vectors, Anopheles darlingi, Anopheles albimanus and Anopheles nuneztovari.Results: Temperature and Normalized Difference Water Index (NDWI) showed a significant correlation with the observed API. The risk map of malaria incidence showed that the zones at higher risk in the Urabá-Bajo Cauca and Alto Sinú region were located south-east of the region, while the northern area presented the lowest malaria risk. A method was generated to estimate the API for small urban centres, instead of the used reports at the municipality level.Conclusions: These results provide evidence of the utility of risk maps to identify environmentally vulnerable areas at a fine spatial resolution in the Urabá-Bajo Cauca and Alto Sinú region. This information contributes to the implementation of vector control interventions at the microgeographic scale at areas of high malaria risk. [ABSTRACT FROM AUTHOR]

Background The relationship between malaria infection and nutritional status is complex. Previous studies suggest malaria may increase the incidence and severity of malnutrition, while malnutrition may increase the risk of malaria infection. Here, we report bidirectional associations between malaria and nutritional status among children with uncomplicated severe acute malnutrition (SAM). Methods This study is a secondary analysis of a randomized, controlled trial for the treatment of uncomplicated SAM in Niger. Children aged 6–59 months were enrolled and followed for 12 weeks. Malaria infection was assessed using an histidine-rich protein 2 (HRP2) rapid diagnostic test at admission and at any follow-up visit with fever. We assessed the association of nutritional status at admission on malaria incidence using Cox proportional hazards regression and malaria infection at admission on nutritional recovery and weight and height gain using linear regression. Results Of 2399 children included in the analysis, 1327 (55.3%) were infected with malaria at admission. Malaria incidence was 12.1 cases/100 person-months among those without malaria infection at admission. Nutritional status at admission was not associated with malaria incidence. Children with malaria infection at admission and subsequently treated with an artemisinin-based combination therapy had increased weight gain (0.38 g/kg/day; 95% confidence interval [CI], 0.07 to 0.69) and reduced height gain (−0.002 mm/day; 95% CI, −0.004 to −0.0008). Conclusions Malaria infection was common among children treated for uncomplicated SAM. Malaria infection may impair height gain. Proper medical and nutritional management should be ensured to prevent adverse effects of malaria infection. Clinical Trials Registration NCT01613547. [ABSTRACT FROM AUTHOR]

We examined anemia and malaria as risk factors for Kaposi sarcoma-associated herpesvirus (KSHV) seropositivity and antibody levels in a long-standing rural Ugandan cohort, in which KSHV is prevalent. Samples from 4134 children, aged 1-17 years, with a sex ratio of 1:1, and 3149 adults aged 18-103 years, 41% of whom were males, were analyzed. Among children, malaria infection was associated with higher KSHV prevalence (61% vs 41% prevalence among malaria infected and uninfected, respectively); malaria was not assessed in adults. Additionally, lower hemoglobin level was associated with an increased prevalence of KSHV seropositivity, both in children and in adults. [ABSTRACT FROM AUTHOR]

We examined transcriptional changes in CD4+ T cells during blood-stage Plasmodium falciparum infection in individuals without a history of previous parasite exposure. Transcription of CXCL8 (encoding interleukin 8) in CD4+ T cells was identified as an early biomarker of submicroscopic P. falciparum infection, with predictive power for parasite growth. Following antiparasitic drug treatment, a CD4+ T-cell regulatory phenotype developed. PD1 expression on CD49b+CD4+ T (putative type I regulatory T) cells after drug treatment negatively correlated with earlier parasite growth. Blockade of PD1 but no other immune checkpoint molecules tested increased interferon γ and interleukin 10 production in an ex vivo antigen-specific cellular assay at the peak of infection. These results demonstrate the early development of an immunoregulatory CD4+ T-cell phenotype in blood-stage P. falciparum infection and show that a selective immune checkpoint blockade may be used to modulate early developing antiparasitic immunoregulatory pathways as part of malaria vaccine and/or drug treatment protocols. [ABSTRACT FROM AUTHOR]

Background: Erythrocyte invasion by malaria parasites is essential for blood-stage development. Consequently, parasite proteins critically involved in erythrocyte invasion, such as the Plasmodium vivax reticulocyte binding proteins (RBPs) that mediate preferential invasion of reticulocytes, are considered potential vaccine targets. Thus, targeting the RBPs could prevent blood-stage infection and disease. The RBPs are large, and little is known about their functional domains and whether individuals naturally exposed to P. vivax acquire binding-inhibitory antibodies to these critical binding regions. This study aims to functionally and immunologically characterize Plasmodium vivax RBP1a.Methods: Recombinant proteins of overlapping fragments of RBP1a were used to determine binding specificity to erythrocytes and immunogenicity in laboratory animals. The naturally acquired antibody response to these proteins was evaluated using serum samples from individuals in regions of endemicity.Results: The N-terminal extracellular region, RBP1157-650 (RBP1:F8), was determined to bind both reticulocytes and normocytes, with a preference for immature reticulocytes. Antibodies elicited against rRBP1:F8 blocked binding between RBP1:F8 and erythrocytes. Naturally acquired anti-RBP1 binding-inhibitory antibodies were detected in serum specimens from P. vivax-exposed individuals from Papua New Guinea and Brazil.Conclusion: Recombinant RBP1:F8 binds human erythrocytes, elicits artificially induced functional blocking antibodies, and is a target of naturally acquired binding-inhibitory antibodies. [ABSTRACT FROM AUTHOR]

Background: Evidence for association between sickle cell and alpha thalassemia trait and severe malaria is compelling. However, for these polymorphisms associations with uncomplicated malaria, and for G6PD deficiency associations with uncomplicated and severe malaria, findings have been inconsistent. We studied samples from a three-arm case-control study with the objective of determining associations between common host erythrocyte polymorphisms and both uncomplicated and severe malaria, including different severe malaria phenotypes. Method: We assessed hemoglobin abnormalities, α-thalassemia, and G6PD deficiency by molecular methods in 325 children with severe malaria age-matched to 325 children with uncomplicated malaria and 325 healthy community controls. Conditional logistic regression was used to measure associations between specified genotypes and malaria outcomes. Results: No tested polymorphisms offered significant protection against uncomplicated malaria. α-thalassemia homozygotes (_α/_α) had increased risk of uncomplicated malaria (OR 2.40; 95%CI 1.15, 5.03, p = 0.020). HbAS and α-thalassemia heterozygous (_α/αα) genotypes protected against severe malaria compared to uncomplicated malaria (HbAS OR 0.46; 0.23, 0.95, p = 0.036; _α/αα OR 0.51; 0.24, 0.77; p = 0.001) or community (HbAS OR 0.23; 0.11, 0.50; p<0.001; _α/αα; OR 0.49; 0.32, 0.76; p = 0.002) controls. The α-thalassemia homozygous (_α/_α) genotype protected against severe malaria when compared to uncomplicated malaria controls (OR 0.34; 95%CI 0.156, 0.73, p = 0.005), but not community controls (OR 1.03; 0.46, 2.27, p = 0.935). Stratifying by the severe malaria phenotype, compared to community controls, the protective effect of HbAS was limited to children with severe anemia (OR 0.17; 95%CI 0.04, 0.65; p = 0.009) and that of _α/αα to those with altered consciousness (OR 0.24; 0.09, 0.59; p = 0.002). A negative epistatic effect was seen between HbAS and _α/αα; protection compared to uncomplicated malaria controls was not seen in individuals with both polymorphisms (OR 0.45; 0.11, 1.84; p = 0.269). G6PD deficiency was not protective against severe malaria. Conclusion: Associations were complex, with HbAS principally protective against severe anemia, _α/αα against altered consciousness, and negative epistasis between the two polymorphisms. [ABSTRACT FROM AUTHOR]

Malaria is a kind of disease that greatly threatens human health. Nearly half of the world’s population is at risk of malaria. Anti-malarial drugs which are sought, developed and synthesized keep malaria under control, having received increasing attention in drug discovery field. Machine learning techniques have been used widely in drug research and development. On the basis of semi-supervised machine learning for molecular descriptions, this research develops a multilayer deep belief network (DBN) that can be used to identify whether compounds have the anti-malarial activity. Firstly, the influence of feature dimensions on predicting accuracy is discussed. Furthermore, the proposed model is applied to contrast shallow machine learning and supervised machine learning with the similar deep architecture. The research results show that the proposed model can predict anti-malarial activity accurately. The stable performance on the evaluation metrics confirms the practicability of our model. The proposed DBN model performs better than other shallow supervised models and deep supervised models. Moreover, it could be applied to reduce the cost and the time of drug discovery. [ABSTRACT FROM AUTHOR]

Arthropods are the largest group of the living organisms. They attack other organisms by biting, stinging, or piercing and sucking. Among various medically important arthropods, which feed on living hosts, mosquitoes’ piercing spread viruses which have been reported to cause the highest number of deaths annually. The primary cause of the deaths is malaria, which is spread by infected mosquitoes’ piercing. This study aims at elucidating lessons from mosquitoes’ painless piercing. Mosquitoes pierce using their fascicle, which is a bundle of coherently functioning six stylets. Based on experiments and available literature, it is presented that mosquitoes painlessly pierce using a combination of the numbing, the fascicle's serrated design, the vibratory actuation, and the graded and frequency-dependent mechanical properties of the labrum. Based on this understanding, a mosquito-inspired microneedle design has also been proposed. [ABSTRACT FROM AUTHOR]

The global increase in vector borne diseases has been linked to climate change. Seasonal vegetation changes are known to influence disease vector population. However, the relationship is more theoretical than quantitatively defined. There is a growing demand for understanding and prediction of climate sensitive vector borne disease risks especially in regions where meteorological data are lacking. This study aimed at analyzing and quantitatively assessing the seasonal and year-to-year association between climatic factors (rainfall and temperature) and vegetation cover, and its implications for malaria risks in Baringo County, Kenya. Remotely sensed temperature, rainfall, and vegetation data for the period 2004–2015 were used. Poisson regression was used to model the association between malaria cases and climatic and environmental factors for the period 2009–2012, this being the period for which all datasets overlapped. A strong positive relationship was observed between the Normalized Difference Vegetation Index (NDVI) and monthly total precipitation. There was a strong negative relationship between NDVI and minimum temperature. The total monthly rainfall (between 94 -181mm), average monthly minimum temperatures (between 16–21°C) and mean monthly NDVI values lower than 0.35 were significantly associated with malaria incidence rates. Results suggests that a combination of climatic and vegetation greenness thresholds need to be met for malaria incidence to be significantly increased in the county. Planning for malaria control can therefore be enhanced by incorporating these factors in malaria risk mapping. [ABSTRACT FROM AUTHOR]

Human malaria remains a major killer disease worldwide, with nearly half (3.2 billion) of the world’s population at risk of malaria infection. The infectious protozoan disease is endemic in tropical and subtropical regions, with an estimated 212 million new cases and 429,000 malaria-related deaths in 2015. An in-host mathematical model of Plasmodium falciparum malaria that describes the dynamics and interactions of malaria parasites with the host’s liver cells (hepatocytic stage), the red blood cells (erythrocytic stage), and macrophages is reformulated. By a theoretical analysis, an in-host basic reproduction number R0 is derived. The disease-free equilibrium is shown to be locally and globally asymptotically stable. Sensitivity analysis reveals that the erythrocyte invasion rate βr, the average number of merozoites released per bursting infected erythrocyte K, and the proportion of merozoites that cause secondary invasions at the blood phase ζ are the most influential parameters in determining the malaria infection outcomes. Numerical results show that macrophages have a considerable impact in clearing infected red blood cells through phagocytosis. Moreover, the density of infected erythrocytes and hence the severity of malaria are shown to increase with increasing density of merozoites in the blood. Concurrent use of antimalarial drugs and a potential erythrocyte invasion-avoidance vaccine would minimize the density of infected erythrocytes and hence malaria disease severity. [ABSTRACT FROM AUTHOR]

A campaign for malaria control, using Long Lasting Insecticide Nets (LLINs) was launched in South Sudan in 2009. The success of such a campaign often depends upon adequate available resources and reliable surveillance data which help officials understand existing infections. An optimal allocation of resources for malaria control at a sub-national scale is therefore paramount to the success of efforts to reduce malaria prevalence. In this paper, we extend an existing SIR mathematical model to capture the effect of LLINs on malaria transmission. Available data on malaria is utilized to determine realistic parameter values of this model using a Bayesian approach via Markov Chain Monte Carlo (MCMC) methods. Then, we explore the parasite prevalence on a continued rollout of LLINs in three different settings in order to create a sub-national projection of malaria. Further, we calculate the model’s basic reproductive number and study its sensitivity to LLINs’ coverage and its efficacy. From the numerical simulation results, we notice a basic reproduction number, , confirming a substantial increase of incidence cases if no form of intervention takes place in the community. This work indicates that an effective use of LLINs may reduce and hence malaria transmission. We hope that this study will provide a basis for recommending a scaling-up of the entry point of LLINs’ distribution that targets households in areas at risk of malaria. [ABSTRACT FROM AUTHOR]

Objectives: To investigate whether high-dosed folate supplements might diminish the efficacy of malaria intermittent preventive treatment in pregnancy (IPTp) with sulphadoxine-pyrimethamine (SP) in a cohort of pregnant women in Benin, where malaria is holoendemic.Methods: We followed 318 women during the entire pregnancy and analysed haematological and Plasmodium falciparum indicators in the context of an intermittent preventive treatment trial in Benin. During the follow-up, women received two-dose IPTp (1500/75 mg of SP per dose) at the maternity clinic and 600 mg of albendazole, 200 mg ferrous sulphate and 5 mg folic acid per day for home treatment.Results: High folate levels were not associated with increased malaria risk (adjusted OR (aOR) = 0.51 (95% CI: 0.17; 1.56, P-value = 0.24)), nor with increased P. falciparum density (beta coefficient = -0.26 (95% CI: -0.53; 0.02), P-value = 0.07) in a randomised trial of IPTp in Benin. On the contrary, higher iron levels were statistically associated with increased odds of a positive blood smear (aOR = 1.7 95% CI (1.2; 2.3), P-value < 0.001) and P. falciparum parasite density (beta coefficient = 0.2 95% CI (0.1; 0.3), P-value < 0.001). High folate levels were statistically associated with decreased odds of anaemia (aOR = -0.30 95% CI (0.10; 0.88), P-value = 0.03).Conclusions: High folate levels are not associated with increased malarial risk in a prospective longitudinal cohort in the context of both iron and high-dosed folate supplements and IPTp. They are associated with reduced risk of anaemia, which is particularly important because iron, also given to treat anaemia, might be associated with increased malaria risk. [ABSTRACT FROM AUTHOR]