Plasmodium falciparum parasite prevalence in East Africa: Updating data for malaria stratification

The High Burden High Impact (HBHI) strategy for malaria encourages countries to use multiple sources of available data to define the sub-national vulnerabilities to malaria risk, including parasite prevalence. Here, a modelled estimate of Plasmodium falciparum from an updated assembly of community parasite survey data in Kenya, mainland Tanzania, and Uganda is presented and used to provide a more contemporary understanding of the sub-national malaria prevalence stratification across the sub-region for 2019. Malaria prevalence data from surveys undertaken between January 2010 and June 2020 were assembled form each of the three countries. Bayesian spatiotemporal model-based approaches were used to interpolate space-time data at fine spatial resolution adjusting for population, environmental and ecological covariates across the three countries. A total of 18,940 time-space age-standardised and microscopy-converted surveys were assembled of which 14,170 (74.8%) were identified after 2017. The estimated national population-adjusted posterior mean parasite prevalence was 4.7% (95% Bayesian Credible Interval 2.6–36.9) in Kenya, 10.6% (3.4–39.2) in mainland Tanzania, and 9.5% (4.0–48.3) in Uganda. In 2019, more than 12.7 million people resided in communities where parasite prevalence was predicted ≥ 30%, including 6.4%, 12.1% and 6.3% of Kenya, mainland Tanzania and Uganda populations, respectively. Conversely, areas that supported very low parasite prevalence (<1%) were inhabited by approximately 46.2 million people across the sub-region, or 52.2%, 26.7% and 10.4% of Kenya, mainland Tanzania and Uganda populations, respectively. In conclusion, parasite prevalence represents one of several data metrics for disease stratification at national and sub-national levels. To increase the use of this metric for decision making, there is a need to integrate other data layers on mortality related to malaria, malaria vector composition, insecticide resistance and bionomic, malaria care-seeking behaviour and current levels of unmet need of malaria interventions.

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Faculty Opinions recommendation of Relationship between Plasmodium falciparum malaria prevalence, genetic diversity and endemic Burkitt lymphoma in Malawi.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718242317.793542339 ◽

2018 ◽

Author(s):

Toshihiro Horii ◽

Nirianne Palacpac

Keyword(s):

Genetic Diversity ◽

Plasmodium Falciparum ◽

Falciparum Malaria ◽

Burkitt Lymphoma ◽

Plasmodium Falciparum Malaria ◽

Malaria Prevalence

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The impact of HIV-associated immunosuppression on the Plasmodium falciparum chloroquine resistance transporter gene (PfCRT) of HIV patients in Akure, Nigeria

Bulletin of the National Research Centre ◽

10.1186/s42269-020-00401-0 ◽

2020 ◽

Vol 44 (1) ◽

Author(s):

Iyabo Adepeju Simon-Oke ◽

Adeola Olanireti Ade-Alao ◽

Foluso Ologundudu

Keyword(s):

Plasmodium Falciparum ◽

Malaria Prevalence ◽

Cd4 Count ◽

Chloroquine Resistance ◽

Hiv Care ◽

Transporter Gene ◽

Hiv Patients ◽

Chloroquine Resistance Transporter ◽

Hiv Test ◽

Low Prevalence

Abstract Background The study evaluated the prevalence of malaria and Plasmodium falciparum chloroquine resistance transporter gene (PfCRT) in HIV patients attending Specialist Hospital, Akure. This study was carried out between April and June 2019. Three hundred and seventeen (317) patients attending the antiretroviral clinic (ART) were involved, out of which 89 (28.08%) were males and 228 (71.92%) were females. HIV test was done using the Unigold® HIV test kit, malaria test was done using thick and thin blood smear, CD4 test was done using the Partec® CD4 counter and PCR was used to detect the presence of plasmodium falciparum mutant gene. The data obtained from this analysis was subjected to Pearson’s Chi-square test. Results The overall result showed low prevalence of malaria (23.03%) in the sampled patients. Highest malaria prevalence (31.0%) was recorded in HIV patients with CD4 count between 200–500 cells/μl of blood, with the males recording 24.7% malaria prevalence. The age group 20–29 years recorded the highest prevalence of 27.3%. A higher prevalence 91.1% of PfCRT gene in HIV-positive and (40.0%) in HIV-negative patients was recorded with 100% prevalence in patients with CD4 count ≤ 200. This shows that the low prevalence of malaria recorded in this study could be credited to good health-seeking attitude of HIV patients and the upscale of HIV care and treatment centres. Conclusion The high prevalence of PfCRT gene shows that treatment of malaria with chloroquine is still being practised despite the availability of artemisinin-based combination therapy (ACTs) as the recommended regimen for malaria treatment.

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The erythrocyte membrane properties of beta thalassaemia heterozygotes and their consequences for Plasmodium falciparum invasion

10.1101/2022.01.13.476158 ◽

2022 ◽

Author(s):

Viola Introini ◽

Alejandro Marin-Menendez ◽

Guilherme Nettesheim ◽

Yen-Chun Lin ◽

Silvia N Kariuki ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Surface Protein ◽

Malaria Prevalence ◽

Membrane Properties ◽

Membrane Tension ◽

Protective Properties ◽

Beta Thalassaemia ◽

Selective Pressures ◽

Bending Modulus ◽

Surface Protein Expression

Malaria parasites such as Plasmodium falciparum have exerted formidable selective pressures on the human genome. Of the human genetic variants associated with malaria protection, beta thalassaemia (a haemoglobinopathy) was the earliest to be associated with malaria prevalence. However, the malaria protective properties of beta thalassaemic erythrocytes remain unclear. Here we studied the mechanics and surface protein expression of beta thalassaemia heterozygous erythrocytes, measured their susceptibility to P. falciparum invasion, and calculated the energy required for merozoites to invade them. We found invasion-relevant differences in beta thalassaemic cells versus matched controls, specifically: elevated membrane tension, reduced bending modulus, and higher levels of expression of the major invasion receptor basigin. However, these differences acted in opposition to each other with respect to their likely impact on invasion, and overall we did not observe beta thalassaemic cells to have lower P. falciparum invasion efficiency for any of the strains tested.

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Extracting and Customizing Information Using Multi-Agents

Web Mining ◽

10.4018/978-1-59140-414-9.ch011 ◽

2011 ◽

pp. 228-252 ◽

Cited By ~ 1

Author(s):

Mohamed Salah Hamdi

Keyword(s):

Main Idea ◽

Complex Environments ◽

Time Data ◽

Client Server ◽

Windows Nt ◽

Distributed Object ◽

Time Space ◽

Multi Agent ◽

Information Customization ◽

Pervasive Access

Rapidly evolving network and computer technology, coupled with the exponential growth of the services and information available on the Internet, has already brought us to the point where hundreds of millions of people should have fast, pervasive access to a phenomenal amount of information, through desktop machines at work, school and home, through televisions, phones, pagers, and car dashboards, from anywhere and everywhere. The challenge of complex environments is therefore obvious: software is expected to do more in more situations, there are a variety of users (Power/Naive, Techie/ Financial/Clerical, ...), there are a variety of systems (Windows/NT/Mac/Unix, Client/Server, Portable, Distributed Object Manager, Web, ...), there are a variety of interactions (Real-time, Data Bases, Other Players, ...), and there are a variety of resources and goals (time, space, bandwidth, cost, security, quality, ...). To cope with such environments, the promise of information customization systems is becoming highly attractive. In this chapter we discuss important problems in relationship to such systems and smooth the way for possible solutions. The main idea is to approach information customization using a multi-agent paradigm.

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Malaria infection status of European Robins seems to associate with timing of autumn migration but not with actual condition

Parasitology ◽

10.1017/s0031182018002184 ◽

2019 ◽

Vol 146 (6) ◽

pp. 814-820

Author(s):

Nóra Ágh ◽

Imre Sándor Piross ◽

Gábor Majoros ◽

Tibor Csörgő ◽

Eszter Szöllősi

Keyword(s):

Avian Malaria ◽

Arrival Time ◽

Parasite Prevalence ◽

Malaria Prevalence ◽

Blood Parasites ◽

Autumn Migration ◽

Actual Condition ◽

Infection Status ◽

Stopover Site ◽

Age Related

AbstractAvian malaria parasites can negatively affect many aspects of the life of the passerines. Though these parasites may strongly affect the health and thus migration patterns of the birds also during autumn, previous studies on avian malaria focused mainly on the spring migration and the breeding periods of the birds. We investigated whether the prevalence of blood parasites varies in relation to biometrical traits, body condition and arrival time in the European Robin (Erithacus rubecula) during autumn migration. We found no sex or age related differences in avian malaria prevalence and no relationship between infection status and body size or actual condition of the birds was found either. However, the timing of autumn migration differed marginally between infected and non-infected juveniles, so that parasitized individuals arrived later at the Hungarian stopover site. This is either because avian malaria infections adversely affect the migration timing or migration speed of the birds, or because later arriving individuals come from more distant populations with possibly higher blood parasite prevalence. The possible delay that parasites cause in the arrival time of the birds during autumn migration could affect the whole migratory strategy and the breeding success of the birds in the next season.

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HIV Testing and Prevalence in Pregnancy in Edinburgh

International Journal of STD & AIDS ◽

10.1177/095646249400500204 ◽

1994 ◽

Vol 5 (2) ◽

pp. 101-104 ◽

Cited By ~ 2

Author(s):

F D Johnstone ◽

R P Brettle ◽

S M Burns ◽

J Peutherer ◽

J Y Q Mok ◽

...

Keyword(s):

Hiv Testing ◽

Injection Drug ◽

Hiv Status ◽

Multiple Sources ◽

Time Data ◽

Related Risk ◽

Changes In Pregnancy ◽

Testing Policies ◽

Hiv Seropositive ◽

In Pregnancy

The objective was to study the changes in pregnancy HIV prevalence with time. Data were collected from multiple sources to provide a comprehensive record of all HIV seropositive pregnant women identified in the Edinburgh area (Scotland) until December 1992. There were 177 pregnancies in 108 HIV seropositive identified women. Risk factors were injection drug use (79% of pregnancies) and a known HIV seropositive injection drug-using partner (16%). Prevalence has decreased for Edinburgh City women from 0.5% of all pregnancies in 1986 to 0.1% in 1992; It was higher for induced abortion (0.6%) than for delivery (0.2%). HIV testing in pregnancy has declined. Comparison with unlinked anonymized testing showed that in 1990–1991, 20/22 seropositive women were known. In 1992, only 3 of 10 seropositive pregnancies were identified. The cohort initially infected by exposure to a ‘drug related’ risk factor between 1983 and 1985 may have increasingly finished childbearing, deliberately decided against pregnancy because of HIV status, and declined because of death, illness and emigration from the area, There may not have been major early tertiary heterosexual spread; however, data from 1992 suggest that this could now be impacting on pregnancy prevalence. Local testing policies have not adapted to this possible change.

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Evaluating effectiveness of screening house eaves as a potential intervention for reducing indoor vector densities and malaria prevalence in Nyabondo, western Kenya

Malaria Journal ◽

10.1186/s12936-020-03413-3 ◽

2020 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Peter Njoroge Ng’ang’a ◽

Collins Okoyo ◽

Charles Mbogo ◽

Clifford Maina Mutero

Keyword(s):

Malaria Parasite ◽

Parasite Prevalence ◽

Malaria Prevalence ◽

Wire Mesh ◽

Control Group ◽

Light Traps ◽

Cross Sectional ◽

Western Kenya ◽

Study Results

Abstract Background Mosquito-proofing of houses using wire mesh screens is gaining greater recognition as a practical intervention for reducing exposure to malaria transmitting mosquitoes. Screening potentially protects all persons sleeping inside the house against transmission of mosquito-borne diseases indoors. The study assessed the effectiveness of house eaves screening in reducing indoor vector densities and malaria prevalence in Nyabondo, western Kenya. Methods 160 houses were selected for the study, with half of them randomly chosen for eaves screening with fibre-glass coated wire mesh (experimental group) and the other half left without screening (control group). Randomization was carried out by use of computer-generated list in permuted blocks of ten houses and 16 village blocks, with half of them allocated treatment in a ratio of 1:1. Cross-sectional baseline entomological and parasitological data were collected before eave screening. After baseline data collection, series of sampling of indoor adult mosquitoes were conducted once a month in each village using CDC light traps. Three cross-sectional malaria parasitological surveys were conducted at three month intervals after installation of the screens. The primary outcome measures were indoor Anopheles mosquito density and malaria parasite prevalence. Results A total of 15,286 mosquitoes were collected over the two year period using CDC light traps in 160 houses distributed over 16 study villages (mean mosquitoes = 4.35, SD = 11.48). Of all mosquitoes collected, 2,872 (18.8%) were anophelines (2,869 Anopheles gambiae sensu lato, 1 Anopheles funestus and 2 other Anopheles spp). Overall, among An. gambiae collected, 92.6% were non-blood fed, 3.57% were blood fed and the remaining 0.47% were composed of gravid and half gravid females. More indoor adult mosquitoes were collected in the control than experimental arms of the study. Results from cross-sectional parasitological surveys showed that screened houses recorded relatively low malaria parasite prevalence rates compared to the control houses. Overall, malaria prevalence was 5.6% (95% CI: 4.2–7.5) n = 1,918, with baseline prevalence rate of 6.1% (95% CI: 3.9–9.4), n = 481 and 3rd follow-up survey prevalence of 3.6% (95% CI: 2.0–6.8) n = 494. At all the three parasitological follow-up survey points, house screening significantly reduced the malaria prevalence by 100% (p < 0.001), 63.6% (p = 0.026), and 100% (p < 0.001) in the 1st, 2nd and 3rd follow-up surveys respectively. Conclusions The study demonstrated that house eave screening has potential to reduce indoor vector densities and malaria prevalence in high transmission areas.

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Adaptive Control of Indoor Thermal Environments Using Fan Coil Units

ASME 2008 2nd International Conference on Energy Sustainability, Volume 2 ◽

10.1115/es2008-54292 ◽

2008 ◽

Cited By ~ 4

Author(s):

Viraj Srivastava ◽

Yun Gu ◽

David Archer

Keyword(s):

Control Systems ◽

Air Conditioning ◽

Control Algorithm ◽

Environmental Control ◽

Feedforward Control ◽

Test Bed ◽

Multiple Sources ◽

Time Data ◽

Distributed Sensor ◽

Thermal Environments

The work described in this paper relates to advanced control systems, specifically designed for heating, ventilation and air conditioning in office buildings. This work specifically focuses on the use of state of the art fan coil units with advanced instrumentation and control. The premise of the work is that control systems can be significantly enhanced by using real-time data from a distributed sensor network deployed in the building. Specifically, the performance of control systems can be improved by augmenting predictive (feed-forward) control operations with techniques to improve the accuracy of models. A control algorithm for heating, ventilating and air-conditioning systems is described in this paper that integrates an advanced feedforward control algorithm with conventional feedback control. This paper further contains a description of a functional prototype used to demonstrate the proposed control algorithm for indoor thermal environmental control. The test-bed used in this work — the Robert L Preger Intelligent Workplace (IW), at Carnegie Mellon University, involves a large number of variables and hence a complex control task, i.e., the test bed contains multiple sources of thermal energy, and multiple constraints and disturbances — both measurable and immeasurable. The algorithms demonstrated in this test-bed are expected to perform satisfactorily on other environments with smaller number of variables. This paper contains a description of experiments that were performed to validate the comfort and energy benefits of increased sensing using fan coil units that are in installed in two spaces in the IW.

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High Prevalence of Markers for Sulfadoxine and Pyrimethamine Resistance in Plasmodium falciparum in the Absence of Drug Pressure in the Ashanti Region of Ghana

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.3.1101-1105.2005 ◽

2005 ◽

Vol 49 (3) ◽

pp. 1101-1105 ◽

Cited By ~ 32

Author(s):

Florian Marks ◽

Jennifer Evans ◽

Christian G. Meyer ◽

Edmund N. Browne ◽

Christa Flessner ◽

...

Keyword(s):

Plasmodium Falciparum ◽

High Frequency ◽

Parasite Prevalence ◽

Cross Resistance ◽

Drug Pressure ◽

Ashanti Region ◽

High Prevalence ◽

Resistance Markers ◽

High Level ◽

Weak Trend

ABSTRACT Markers of Plasmodium falciparum resistance to chloroquine (CQ) and pyrimethamine-sulfadoxine (PYR-SDX) are widespread in areas where malaria is endemic. In an area where the use PYR-SDX is negligible, the Ashanti Region of Ghana, West Africa, adult individuals were enrolled in an analysis of CQ- and PYR-SDX-associated molecular resistance markers in 2001 (n = 177) and 2003 (n = 180). Parasite prevalence, as assessed by PCR assays, were 56.5 and 48.8% in 2001 and 2003, respectively. A high frequency of CQ, PYR, and SDX resistance markers was observed, whereby, as a weak trend, the frequency was higher in 2003. The quintuple combination of three pfdhfr mutations and two pfdhps mutations has previously been recognized to be the most important determinant of PYR-SDX resistance. Approximately 60% of parasite carriers harbored fourfold mutated parasites, indicative of a considerable risk for a switch to high-level PYR-SDX resistance in an area where the rate of PYR-SDX use is low. Among the factors contributing to the high frequency of PYR-SDX resistance-associated mutations are background use of PYR-SDX, past use of PYR for malaria prophylaxis, cross-resistance of trimethoprim with PYR, and the sufficient biological fitness of resistant parasites in the absence of drug pressure.

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