Prevalence Of Plasmodium Falciparum Research Articles

A cross-sectional study investigating malaria prevalence and associated predictors of infection among migrants to a newly established gold mining settlement in the Gambella Region of Ethiopia.

Malaria is a major disease burden in Ethiopia. Migration can influence malaria transmission dynamics, with individuals relocating from malaria-free highland regions to malarious lowlands potentially facing elevated risks of contracting malaria. Migrants may find it difficult to protect themselves against malaria and have limited access to diagnosis or treatment. Settlers in gold mining sites are one type of migrant and are often neglected in malaria research yet may have particularly high malaria risk. This study was a malaria prevalence survey among settlers in a new gold mining settlement in the highly malarious Gambella Region, Ethiopia. n = 590 people were surveyed for demographic information and their knowledge and practices of malaria. Participants were tested for malaria using rapid diagnostic tests and microscopy. Using logistic regressions, the influence of demographic characteristics on malaria infections and bed net access were analysed. A sub-sample of participants was interviewed to comprehend settlement living conditions and healthcare accessibility. The overall prevalence of Plasmodium falciparum was 37.5% (CI 32.4-42.3%). Young children were most likely to have malaria, with individuals aged 15-24 having 67% lower odds (aOR: 0.33; CI 0.13-0.86) of infection compared to those aged 1-4years old. Meanwhile, those age 25-plus had 75% decreased odds of malaria infection (aOR 0.25; CI 0.10-0.65). Individuals with bed nets had ~50% decreased odds of testing positive for falciparum malaria than those reporting having no bed net (aOR: 0.47; CI 0.22-0.97). Individuals who relocated from low elevation with high malaria test positivity rate areas were more prone to testing positive for malaria, as were those residing in densely populated households with multiple malaria cases. Conversely, individuals from higher elevations with low malaria test positivity rates, and those living in households with 5-10 occupants and < 2 malaria infections, were more likely to possess bed nets. This gold mining settlement provides an example of an oft-neglected atypical community where malaria is a significant, but under-addressed, health problem. Within this community, future interventions focused on distributing bed nets, particularly to larger households and those with children, have great potential to alleviate the malaria burden. Efforts should also be made to provide affordable, and accessible, early diagnosis and treatment.

Adapting malaria indicator surveys to investigate treatment adherence: a pilot study on Bioko Island, Equatorial Guinea

BackgroundAdherence to anti-malarial treatment regimens is an important aspect of understanding and improving the impact of malaria case management. However, both adherence to artemisinin-based combination therapy (ACT) and the factors driving it vary widely. While many other evaluation activities have been conducted on Bioko Island, until now adherence to anti-malarial treatments, and in particular ACT has not been evaluated.MethodsThe implementation of a malaria indicator survey (MIS) conducted on Bioko in 2023 was leveraged to evaluate adherence to ACT provided to individuals testing positive following the survey. A follow-up team visited the targeted households, physically observed treatment blisters where possible, and provided messaging to household members on the importance of adhering to the treatment guidelines to household members. The team used survey data from the targeted households to make messaging as relevant to the household’s particular context as possible.ResultsOverall ACT adherence on Bioko Island was low, around 50%, and this varied demographically and geographically. Some of the highest transmission areas had exceptionally low adherence, but no systematic relationship between proper adherence and Plasmodium falciparum prevalence was detected. Estimates of adherence from follow-up visits were much lower than survey-based estimates in the same households (52.5% versus 87.1%), suggesting that lack of proper adherence may be a much larger issue on Bioko Island than previously thought.ConclusionRepresentative surveys can be easily adapted to provide empirical estimates of adherence to anti-malarial treatments, complementary to survey-based and health facility-based estimates. The large discrepancy between adherence as measured in this study and survey-based estimates on Bioko Island suggests a health facility-based study to quantify adherence among the population receiving treatment for symptomatic malaria may be necessary.

From multiplicity of infection to force of infection for sparsely sampled Plasmodium falciparum populations at high transmission.

High multiplicity of infection or MOI, the number of genetically distinct parasite strains co-infecting a single human host, characterizes infectious diseases including falciparum malaria at high transmission. It accompanies high asymptomatic Plasmodium falciparum prevalence despite high exposure, creating a large transmission reservoir challenging intervention. High MOI and asymptomatic prevalence are enabled by immune evasion of the parasite achieved via vast antigenic diversity. Force of infection or FOI, the number of new infections acquired by an individual host over a given time interval, is the dynamic sister quantity of MOI, and a key epidemiological parameter for monitoring the impact of antimalarial interventions and assessing vaccine or drug efficacy in clinical trials. FOI remains difficult, expensive, and labor-intensive to accurately measure, especially in high-transmission regions, whether directly via cohort studies or indirectly via the fitting of epidemiological models to repeated cross-sectional surveys. We propose here the application of queuing theory to obtain FOI on the basis of MOI, in the form of either a two-moment approximation method or Little's law. We illustrate these methods with MOI estimates obtained under sparse sampling schemes with the recently proposed " coding" method, based on sequences of the multigene family encoding for the major variant surface antigen of the blood stage of malaria infection. The methods are evaluated with simulation output from a stochastic agent-based model, and are applied to an interrupted time-series study from Bongo District in northern Ghana before and immediately after a three-round transient indoor residual spraying (IRS) intervention. We incorporate into the sampling of the simulation output, limitations representative of those encountered in the collection of field data, including under-sampling of genes, missing data, and usage of antimalarial drug treatment. We address these limitations in MOI estimates with a Bayesian framework and an imputation bootstrap approach. We demonstrate that both proposed methods give good and consistent FOI estimates across various simulated scenarios. Their application to the field surveys shows a pronounced reduction in annual FOI during intervention, of more than 70%. The proposed approach should be applicable to the many geographical locations where cohort or cross-sectional studies with regular and frequent sampling are lacking but single-time-point surveys under sparse sampling schemes are available, and for MOI estimates obtained in different ways. They should also be relevant to other pathogens of humans, wildlife and livestock whose immune evasion strategies are based on large antigenic variation resulting in high multiplicity of infection.

The Declined Trend of Malaria over a Ten-year Period in the Rural East Nusa Tenggara Province, Indonesia: A Medical Record Analysis

BACKGROUND: Malaria still remains a major public health problem globally including in Indonesia. At present, most of malaria cases are in the eastern part of the country. However, there is no information yet regarding the trends of malaria prevalence at rural health institution particularly at Mangili Public Health Centre. AIM: This study aims to explore the trend of malaria prevalence over a 10-year period. METHODS: A retrospective study was carried out in the center. The laboratory record books from January 2013 to December 2022 were carefully reviewed to identify malaria cases based on the sex, age, type of Plasmodium, year, and month when the patients diagnosed malaria microscopically. The trend analysis was applied to identify the trend of malaria over the period under review. RESULTS: Over the past 10 years, 19,938 blood films were requested for malaria diagnosis at the health center. From this number, 3.679 (18.5%, with 95% confidence interval (CI): 17.2–19.7) were microscopically confirmed malaria cases. From the total cases, prevalence of Plasmodium falciparum (Pf), vivax and mix infection was 85.5% with 95% CI: 84.3–86.8; 6.39% with 95% CI: 3.26–9.51; and 7.58% with 95% CI: 4.48–10.7, respectively. The number of malaria cases reached a peak in January, while it was the lowest in October. Overall trend on the prevalence of malaria decreased significantly; however, the prevalence of Pf increased considerably during COVID-19 pandemic. The prevalence of Pf, vivax, and mixed infection was higher in male, age group ≥ 15, and student than their counterpart. CONCLUSION: Malaria remains high in this area with Pf that is the dominant species followed by mixed infection. Scaling up malaria control and prevention activities is very crucial to significantly reduce the burden of malaria and to boost malaria elimination in this region.

Prevalence of Malaria Infection in Pregnant Women Attending Antenatal Clinics in Southern Senegal.

Despite marked progress in Senegal, three regions in the southeast part continue to have a high burden of malaria, but there have been no recent studies assessing the prevalence of malaria associated with pregnancy. This study aimed to determine the prevalence of malaria infection in pregnant women attending antenatal clinics in Senegal. During the malaria transmission season of 2019, pregnant women attending 11 health care facilities for a scheduled visit and those presenting unwell with signs of malaria were invited to participate in a malaria screening study. A finger prick blood sample was taken for malaria diagnosis by rapid diagnosis test (RDT) and polymerase chain reaction (PCR). A total of 877 pregnant women were enrolled, 787 for a scheduled antenatal consultation and 90 for an unscheduled consultation with signs of malaria. The prevalence of Plasmodium falciparum among the first group was 48% by PCR and 20% by RDT, and that among the second group was 86% by PCR and 83% by RDT. RDT sensitivity in capturing asymptomatic, PCR-positive infections was 9.2% but ranged from 83% to 94% among febrile women. The prevalence of infection by PCR in women who reported having received at least three doses of sulfadoxine pyrimethamine (SP) was 41.9% compared with 58.9% in women who reported they had not received any SP doses (prevalence ratio adjusted for gravidity and gestational age, 0.54; 95% CI, 0.41-0.73). The burden of P. falciparum infections remains high among pregnant women, the majority of which are not captured by RDT. More effective measures to prevent malaria infection in pregnancy are needed.

Using a mobile nanopore sequencing lab for end-to-end genomic surveillance of Plasmodium falciparum: A feasibility study.

Genomic epidemiology holds promise for malaria control and elimination efforts, for example by informing on Plasmodium falciparum genetic diversity and prevalence of mutations conferring anti-malarial drug resistance. Limited sequencing infrastructure in many malaria-endemic areas prevents the rapid generation of genomic data. To address these issues, we developed and validated assays for P. falciparum nanopore sequencing in endemic sites using a mobile laboratory, targeting key antimalarial drug resistance markers and microhaplotypes. Using two multiplexed PCR reactions, we amplified six highly polymorphic microhaplotypes and ten drug resistance markers. We developed a bioinformatics workflow that allows genotyping of polyclonal malaria infections, including minority clones. We validated the panels on mock dried blood spot (DBS) and rapid diagnostic test (RDT) samples and archived DBS, demonstrating even, high read coverage across amplicons (range: 580x to 3,212x median coverage), high haplotype calling accuracy, and the ability to explore within-sample diversity of polyclonal infections. We field-tested the feasibility of rapid genotyping in Zanzibar in close collaboration with the local malaria elimination program using DBS and routinely collected RDTs as sample inputs. Our assay identified haplotypes known to confer resistance to known antimalarials in the dhfr, dhps and mdr1 genes, but no evidence of artemisinin partial resistance. Most infections (60%) were polyclonal, with high microhaplotype diversity (median HE = 0.94). In conclusion, our assays generated actionable data within a few days, and we identified current challenges for implementing nanopore sequencing in endemic countries to accelerate malaria control and elimination.

Prevalence and Molecular Detection of Plasmodium falciparum among Pregnant Women Attending Selected Hospitals in Kaduna North Local Government Area, Kaduna State

Pregnancy-related malaria is a serious public health issue that significantly raises the risk of death for both mothers and babies in malaria-endemic nations. This study was carried out to determine the prevalence of malaria and molecularly detect Plasmodium falciparumamong pregnant women attending selected hospitals in Kaduna North Local Government Area, Kaduna State.Blood samples were collected from 309 pregnant women attending BarauDikko Teaching Hospital Kaduna, General Hospital Kawo and Nigerian Defence Academy Hospital Kaduna. The samples were analysed microscopically and molecularly for Plasmodium falciparum. A self-administered questionnaire was administered to each pregnant woman to obtain information such as occupation, age and gestation period. Results show a prevalence of 65.0% forPlasmodium falciparum malaria among the pregnant women with significant (p &lt; 0.05) difference between malaria and sampling location. The highest prevalence was recorded in pregnant women attending General Hospital Kawo with a prevalence of 76.9%, followed by women attending NDA hospital with a prevalence of 65.0% and those attending Barau Dikko Teaching Hospital had 53.4%. %). Prevalence of Plasmodium falciparum was seen higher in women in their second trimester of pregnancy with 68.9% prevalence, younger aged pregnant women with 66.7% prevalence and self-employed pregnant women with 66.2% prevalence. Results further showed that out of 12 samples with high parasite density subjected to molecular analysis, only 5 (41.7%) were positive for Plasmodium falciparum. The study revealed the prevalence of 65.0% of P falciparum infection among pregnant women attending selected hospitals in the studied area. Adequate utilization of insecticide treated net is essential to prevent exposure to mosquito bites leading to reduction in maternal mortality.

High prevalence of asymptomatic malaria in Forest Guinea: Results from a rapid community survey.

Malaria is endemic in Guinea; however, the extent and role in transmission of asymptomatic malaria are not well understood. In May 2023, we conducted a rapid community survey to determine Plasmodium falciparum (P. falciparum) prevalence among asymptomatic individuals in Middle Guinea (Prefecture Dalaba) and Forest Guinea (Prefecture Guéckédou). In Dalaba, 6 of 239 (2.1%, confidence interval (CI) 0.9-4.8%) individuals tested positive for P. falciparum by a rapid diagnostic test (RDT), while in Guéckédou, 147 of 235 (60.9%, CI 54.5-66.9%) participants tested positive. Asymptomatic malaria needs to be considered more strongly as a driver of transmission when designing control strategies, especially in Forest Guinea and potentially other hyper-endemic settings.

Dihydroartemisinin-piperaquine efficacy in Plasmodium falciparum treatment and prevalence of drug-resistant molecular markers along China-Myanmar border in 2014–2023

The study aims to monitor dihydroartemisinin-piperaquine (DHA-PPQ) efficacy in Plasmodium falciparum and detect molecular markers associated with its resistance. The World Health Organization's standard protocol for therapeutic efficacy studies (TES) was performed from 2014 to 2018; integrated drug efficacy surveillance (iDES) was performed from from 2019 to July 2023. Molecular markers were detected by polymerase chain reaction. The association between gene mutations and delayed parasite clearance was analysed by multivariate logistic regression analysis. A total of 226 P. falciparum patients were enrolled in the TES from 2014 to 2018, and 26 patients with P. falciparum from Africa were recruited in the iDES from 2019 to July 2023. The PCR-adjusted clinical and parasitological cure rate was 93.7% (95% CI: 92.6-99.5%) in the TES and 96.2% (95% CI: 80.4-99.9%) in the iDEs. Twelve mutants and an overall 55.0% prevalence of pfK13 mutations were detected. Of them, G533S, C447R, C447S, N458Y, C469Y, and A676D were first detected out along the China-Myanmar border. Referred to the wild strain, adjusted odds ratios of treatment failure for G533S, N458Y, and P574L by 42 days were 7.54 (95% CI: 1.605-45.86), 13.68 (95% CI: 1.95-130.72), and 89.00 (95% CI: 1.98-2482.1), respectively. The efficacy of DHA-PPQ from 2014 to 2018 declined in comparison with 2003 to 2013, but it is still effective for treatment of P. falciparum malaria. Results of the iDES indicate a risk of artemisinin resistance in Africa. G533S, N458Y, and P574L are associated with delayed parasite clearance and treatment failure.

Increasing prevalence of malaria and acute dengue virus coinfection in Africa: a meta-analysis and meta-regression of cross-sectional studies

BackgroundMalaria and dengue fever are the leading causes of acute, undifferentiated febrile illness. In Africa, misdiagnosis of dengue fever as malaria is a common scenario. Through a systematic review of the published literature, this study seeks to estimate the prevalence of dengue and malaria coinfection among acute undifferentiated febrile diseases in Africa.MethodsRelevant publications were systematically searched in the PubMed, Cochrane Library, and Google Scholar until May 19, 2023. A random-effects meta-analysis and meta-regression were used to summarize and examine the prevalence estimates.ResultsTwenty-two studies with 22,803 acute undifferentiated febrile patients from 10 countries in Africa were included. The meta-analysis findings revealed a pooled prevalence of malaria and dengue coinfection of 4.2%, with Central Africa having the highest rate (4.7%), followed by East Africa (2.7%) and West Africa (1.6%). Continent-wide, Plasmodium falciparum and acute dengue virus coinfection prevalence increased significantly from 0.9% during 2008–2013 to 3.8% during 2014–2017 and to 5.5% during 2018–2021 (p = 0.0414).ConclusionThere was a high and increasing prevalence of malaria and acute dengue virus coinfection in Africa. Healthcare workers should bear in mind the possibility of dengue infection as a differential diagnosis for acute febrile illness, as well as the possibility of coexisting malaria and dengue in endemic areas. In addition, high-quality multicentre studies are required to verify the above conclusions.Protocol registration number: CRD42022311301.

Asymptomatic Malaria During Pregnancy: Prevalence, Influence on Anemia and Associated Factors in West Guji Zone, Ethiopia - A Community-Based Study.

Pregnant women with asymptomatic malaria parasitemia are at increased risk of anaemia, stillbirth, miscarriage, and preterm delivery. The asymptomatic nature of the population makes diagnosis difficult, and there is generally a lack of urgency to address this specific outcome. This study aimed to determine the prevalence of asymptomatic malaria and associated factors among pregnant women in West Guji Zone, Oromia, Ethiopia. A community-based cross-sectional study was conducted among randomly selected 557 asymptomatic pregnant women in the West Guji Zone from February to March 2022. A standardized questionnaire was used to collect information on socio-demographic and obstetric characteristics. Approximately 2 milliliters of peripheral blood was collected for microscopy to identify species and parasite density. Epi-Data and SPSS were used for data entry and analysis respectively. Binary logistic regression was used to identify risk factors. The prevalence of malaria among asymptomatic pregnant women was 24.10% (95% CI: 20.55%-27.65%). The prevalence of Plasmodium vivax and falciparum prevalence was 73 (54.5%) and 61 (45.5%), respectively. Of the study subjects, 105 (78.4%) had mild parasitemia and 29 (21.6%) had moderate parasitemia. Pregnant women with Plasmodium infection were anaemic in two-thirds (66.5%) of cases. Living near standing water (AOR=2.6, 95% CI: 1.74-3.96), having a history of Plasmodium species infection (AOR=2.12, 95% CI: 1.36-3.31), not using indoor residual spraying (AOR=2.0, 95% CI: 1.32-3.14), and not using insecticide-treated bed nets (AOR=1.62, 95% CI: 1.02-2.55) were all factors that were significantly associated with asymptomatic infection. Pregnant women with Plasmodium infection had a significantly higher rate of anaemia than those who were not infected (OR = 6.31, p = 0.000). Pregnant women had a significant prevalence of asymptomatic Plasmodium infection. Regular screening, appropriate treatment for those who test positive, and health education for pregnant women should be provided by the West Guji Zone Health Bureau.

Dynamics of &lt;i&gt;Plasmodium falciparum&lt;/i&gt; Parasitaemia and Uncomplicated Malaria among School-Age Children living in Omoku, Southern Nigeria

This cross-sectional study determined the mean parasitaemia and prevalence of Plasmodium falciparum malaria parasites among school-aged children in Omoku, Ogba Egbema Ndoni Local Government Area, Rivers State, Southern Nigeria. A total of 200 blood samples were randomly collected through convenience sampling method from the study subjects. Malaria diagnosis was carried out using standard parasitological techniques. The demographic data of the subjects showed that more females, 126(63%), were examined compared with males, 74(37%). Overall prevalence of Plasmodium falciparum recorded was 49%. Gender-based prevalence showed that more females were infected 58(29%) with mean parasite density of 16524(1611) parasites/μL of blood than males, 40 (20%) with mean parasite density of 14886(1794) parasites/μL of blood. The difference in prevalence between them was statistically significant (P &lt; 0.05). Age-related prevalence showed that those within the age range of 5 to 7 years had the highest prevalence, 48(24%), with mean parasite density of 14909(1244) parasites/μL of blood, followed by those within the age range of 8 to 10 years, 34(17%), with mean parasite density of 11434(1244) parasites/μL of blood, while those within the age range of 11 to 13 years had the lowest prevalence, 16(8%), with mean parasite density of 5067(568) parasites/μL of blood. However, the difference between them was not statistically significant (P &gt;0.05). The prevalence of malaria based on schools attended by the subjects showed that BMA had the highest, 12%, and mean parasite density of 6995(827) parasites/μL of blood, while SIS, and EIS had the lowest percentage of infections, 8%, respectively (P&gt;0.05).The association between mother’s level of education, household size and P. falciparum parasitized children was statistically significant (P&lt;0.05). In conclusion, malaria is endemic in the study area, and among other interventions, scaling up investment in primary health care is necessary to effectively prevent, detect, and treat malaria in local communities.

Effects of uncomplicated malaria parasitaemia on selected haematological parameters and phagocytes of children living in Port Harcourt, Southern Nigeria

This cross-sectional and case control study evaluated the effects of malaria parasites on selected haematological parameters of children living in Port Harcourt, Nigeria. A total of 352 participants were randomly recruited and their blood samples collected. Malaria diagnosis and estimation of haematological parameters were determined using standard parasitological and haematological methods respectively. Sociodemographics of participants showed that 109 (31%) of female children and 106 (30%) of male children were infected with malaria parasites. Overall prevalence of Plasmodium falciparum found was 215(61%). The study found a statistically significant difference in the mean values of packed cell volume (PCV), haemoglobin concentration (Hb), and white blood cell count (WBC) of Plasmodium parasitized children compared with their matched controls: PCV(34.83±2.76% versus 36.06±1.41%; P=0.001); Hb(11.58±0.92g/dL versus 11.98±0.46g/dL; P=0.001); WBC (8.96±4.56(x109/L) versus 7.33±1.39(x109/L); P=0.001).While the mean values of lymphocyte counts were relatively reduced in malaria infected children than their control participants (41.66±13.57(x109/L) versus 42.95±8.36(x109/L); P=0.27). A weak relationship was found to exist between density of parasitaemia and ages of children infected with malaria parasites (R2=0.0093; P=0.1584). Though more children had low parasitaemia (1-999 parasites/μL), followed with high parasitaemia (&gt;10,000 parasites/μL), while few had moderate parasitaemia (1000-9999 parasites/μL). There was no case of complication with respect to WHO standard which described complicated or severe anaemia in malaria as haemoglobin (Hb) of &lt; 5g/dl or packed cell volume (PCV) of &lt; 15% with parasitemia of &gt; 250,000 parasites/μL. Malaria parasites affect outcomes of some haematological parameters. We recommend that all febrile children in our study area should be tested for malaria parasites in conjunction with estimation of their full blood count for effective malaria diagnosis and treatment particularly in sub patent cases.

Evaluation of Incidence of Asymptomatic Plasmodium Falciparum in a Peri-Urban Community in Ogun, Nigeria

Malaria has been a public health concern in most tropical and sub-tropical countries around the world with causative agents by five Plasmodium species. Malaria is a prominent disease of high-temperature regions with high morbidity, leading to socio-economic loss. Pregnancy asymptomatic Plasmodium species infection causes placental infection and anaemia; separation of infected red blood cells in the mother intervillous spaces of the placenta resulted in its infection and is associated with placental inflammation and fibrosis. Screening for individuals with asymptomatic infections to determine their prevalence and possibly control it is pertinent using sensitive cum precise diagnostic tools. This study aim's at evaluating the incidence of asymptomatic plasmodium falciparum in the study area. Two hundred and ten blood samples were collected randomly from Ogun State Polytechnic of Health and Allied Science, Ilese Campus; this constituted students and staffers with asymptomatic Plasmodium falciparum between February and March 2023. The students and staffers exhibiting any symptoms of Malaria infection, such as fever, nausea, chills, etc., and on anti-malaria drugs were excluded from the tested population. The male volunteer was 15.2% (32/ 210) while the female was 84.8%, reflecting the nature of the population's gender skewness being a female-dominated place. The age distribution, 17-26 years age group was high with 59%; 27-36 was 13.8%, 37-46 with 17.6%, 47-56; 7.6%, 57-65+ being lowest with 1.9%. The prevalence of plasmodium falciparum in the blood of subjects in this study was 87%; the male infected was 18%, and the female was 68.6%.

Impact of malaria diagnostic choice on monitoring of Plasmodium falciparum prevalence estimates in the Democratic Republic of the Congo and relevance to control programs in high-burden countries.

Malaria programs rely upon a variety of diagnostic assays, including rapid diagnostic tests (RDTs), microscopy, polymerase chain reaction (PCR), and bead-based immunoassays (BBA), to monitor malaria prevalence and support control and elimination efforts. Data comparing these assays are limited, especially from high-burden countries like the Democratic Republic of the Congo (DRC). Using cross-sectional and routine data, we compared diagnostic performance and Plasmodium falciparum prevalence estimates across health areas of varying transmission intensity to illustrate the relevance of assay performance to malaria control programs. Data and samples were collected between March-June 2018 during a cross-sectional household survey across three health areas with low, moderate, and high transmission intensities within Kinshasa Province, DRC. Samples from 1,431 participants were evaluated using RDT, microscopy, PCR, and BBA. P. falciparum parasite prevalence varied between diagnostic methods across all health areas, with the highest prevalence estimates observed in Bu (57.4-72.4% across assays), followed by Kimpoko (32.6-53.2%), and Voix du Peuple (3.1-8.4%). Using latent class analysis to compare these diagnostic methods against an "alloyed gold standard," the most sensitive diagnostic method was BBA in Bu (high prevalence) and Voix du Peuple (low prevalence), while PCR diagnosis was most sensitive in Kimpoko (moderate prevalence). RDTs were consistently the most specific diagnostic method in all health areas. Among 9.0 million people residing in Kinshasa Province in 2018, the estimated P. falciparum prevalence by microscopy, PCR, and BBA were nearly double that of RDT. Comparison of malaria RDT, microscopy, PCR, and BBA results confirmed differences in sensitivity and specificity that varied by endemicity, with PCR and BBA performing best for detecting any P. falciparum infection. Prevalence estimates varied widely depending on assay type for parasite detection. Inherent differences in assay performance should be carefully considered when using community survey and surveillance data to guide policy decisions.

Protocol for a cluster randomised placebo-controlled trial of adjunctive ivermectin mass drug administration for malaria control on the Bijagós Archipelago of Guinea-Bissau: the MATAMAL trial

IntroductionAs malaria declines, innovative tools are required to further reduce transmission and achieve elimination. Mass drug administration (MDA) of artemisinin-based combination therapy (ACT) is capable of reducing malaria transmission where...

Assessment of Malaria Related Anemia and Underweight in Under-Five Age Children in Estie Woreda, South Gondar Zone of Amhara Region, South East Ethiopia

Background: Malaria remains a challenging health problem in malaria endemic regions. Malaria associated anemia represent a major public health problem in sub-Saharan Africa. Both, anemia (reduced in hemoglobin level) and underweight in terms of (weight-for-age) was a critical problem of malaria directly or indirectly. The objective of this study was to assess malaria related anemia and malaria related underweight among under-five years age children in Arushe wanqat kebele. Children’s were selected through systematic random sampling technique to select the first children from new vital event registration master list of Arushe wanqat kebele, and then totally 364 children were included. Parasitological, hematological and anthropometric measurements were conducted. Questionnaire survey was also used in order to assess malaria related anemia and weight on children whose age were below five years. Data was analyzed using SPSS software version 20 and was presented in frequency, table, pie chart, bar graph and percentage form. Analysis of Variance (ANOVA), correlation(r), and Chi-square (X2) tests were used to verify the possible association between Plasmodiums pecies, anemia, and underweight at different age (in months). Results: Prevalence of Plasmodium falciparum accounted for 101(27.8%), Plasmodium vivax accounted for 84(23.1%), and mixed infection (both P. falciparum and P. vivax) also accounted for 14(3.8%). The correlation (r) between Plasmodium species and hemoglobin concentration (r = 0.628; p = 0.000); Plasmodium species and weight measure (r = 0.77; p = 0.000). The prevalence of malaria related anemia and underweight were 70.4% and 51.3%, respectively. Plasmodium falciparum is the most prevalent species and a notorious cause of anemia among children who were less than five years old. Both anemia (reduction of Hb. in g/dl) and underweight have a positive linear relationship. Malaria-related anemia was also more prevalent than malaria-related underweight among children. The result of the study indicates that there was a strong association between malaria and anemia (association is significant between Plasmodium species and hemoglobin concentration; p &lt; 0.05); there is also an association between malaria and weight loss or underweight (association is significant between Plasmodium species and weight-for-age z-score; p &lt; 0.05) at different age groups. Conclusion: The prevalence malaria-related anemia among children in Arushe wanqat kebele was 38.67%.On the other hand, the prevalence of malaria-related weight loss or underweight among children in Arushe wanqat kebele was 28.02%. So, the findings of this study also revealed that malaria remains a public health problem that contributes for anemia and underweight on under five children.

Acceptability, Feasibility, Drug Safety, and Effectiveness of a Pilot Mass Drug Administration with a Single Round of Sulfadoxine-Pyrimethamine Plus Primaquine and Indoor Residual Spraying in Communities with Malaria Transmission in Haiti, 2018.

For a malaria elimination strategy, Haiti's National Malaria Control Program piloted a mass drug administration (MDA) with indoor residual spraying (IRS) in 12 high-transmission areas across five communes after implementing community case management and strengthened surveillance. The MDA distributed sulfadoxine-pyrimethamine and single low-dose primaquine to eligible residents during house visits. The IRS campaign applied pirimiphos-methyl insecticide on walls of eligible houses. Pre- and post-campaign cross-sectional surveys were conducted to assess acceptability, feasibility, drug safety, and effectiveness of the combined interventions. Stated acceptability for MDA before the campaign was 99.2%; MDA coverage estimated at 10 weeks post-campaign was 89.6%. Similarly, stated acceptability of IRS at baseline was 99.9%; however, household IRS coverage was 48.9% because of the high number of ineligible houses. Effectiveness measured by Plasmodium falciparum prevalence at baseline and 10 weeks post-campaign were similar: 1.31% versus 1.43%, respectively. Prevalence of serological markers were similar at 10 weeks post-campaign compared with baseline, and increased at 6 months. No severe adverse events associated with the MDA were identified in the pilot; there were severe adverse events in a separate, subsequent campaign. Both MDA and IRS are acceptable and feasible interventions in Haiti. Although a significant impact of a single round of MDA/IRS on malaria transmission was not found using a standard pre- and post-intervention comparison, it is possible there was blunting of the peak transmission. Seasonal malaria transmission patterns, suboptimal IRS coverage, and low baseline parasitemia may have limited the effectiveness or the ability to measure effectiveness.

Similar Prevalence of Plasmodium falciparum and Non-P. falciparum Malaria Infections among Schoolchildren, Tanzania1.

Achieving malaria elimination requires considering both Plasmodium falciparum and non-P. falciparum infections. We determined prevalence and geographic distribution of 4 Plasmodium spp. by performing PCR on dried blood spots collected within 8 regions of Tanzania during 2017. Among 3,456 schoolchildren, 22% had P. falciparum, 24% had P. ovale spp., 4% had P. malariae, and 0.3% had P. vivax infections. Most (91%) schoolchildren with P. ovale infections had low parasite densities; 64% of P. ovale infections were single-species infections, and 35% of those were detected in low malaria endemic regions. P. malariae infections were predominantly (73%) co-infections with P. falciparum. P. vivax was detected mostly in northern and eastern regions. Co-infections with >1 non-P. falciparum species occurred in 43% of P. falciparum infections. A high prevalence of P. ovale infections exists among schoolchildren in Tanzania, underscoring the need for detection and treatment strategies that target non-P. falciparum species.

Association between domesticated animal ownership and Plasmodium falciparum parasite prevalence in the Democratic Republic of the Congo: a national cross-sectional study

Domesticated animal ownership is an understudied aspect of the human environment that influences mosquito biting behaviour and malaria transmission, and is a key part of national economies and livelihoods in malaria-endemic regions. In this study, we aimed to understand differences in Plasmodium falciparum prevalence by ownership status of common domesticated animals in DR Congo, where 12% of the world's malaria cases occur and anthropophilic Anopheles gambiae vectors predominate. In this cross-sectional study, we used survey data from individuals aged 15-59 years in the most recent (2013-14) DR Congo Demographic and Health Survey and previously performed Plasmodium quantitative real-time PCR (qPCR) to estimate P falciparum prevalence differences by household ownership of cattle; chickens; donkeys, horses, or mules; ducks; goats; sheep; and pigs. We used directed acyclic graphs to consider confounding by age, gender, wealth, modern housing, treated bednet use, agricultural land ownership, province, and rural location. Of 17 701 participants who had qPCR results and covariate data, 8917 (50·4%) of whom owned a domesticated animal, we observed large differences in malaria prevalence across types of animals owned in both crude and adjusted models. Household chicken ownership was associated with 3·9 (95% CI 0·6 to 7·1) more P falciparum infections per 100 people, whereas cattle ownership was associated with 9·6 (-15·8 to -3·5) fewer P falciparum infections per 100 people, even after accounting for bednet use, wealth, and housing structure. Our finding of a protective association conferred by cattle ownership suggests that zooprophylaxis interventions might have a role in DR Congo, possibly by drawing An gambiae feeding away from humans. Studies of animal husbandry practices and associated mosquito behaviours could reveal opportunities for new malaria interventions. The National Institutes of Health and the Bill & Melinda Gates Foundation. For the French and Lingala translations of the abstract see Supplementary Materials section.