Malaria Journal最新文献

{"title":"Healthcare workers' knowledge and acceptance of the malaria vaccine in the Nanoro Health District of Burkina Faso: a cross-sectional study.","authors":"Jean-Vincent Lamien, Bérenger Kaboré, Karim Derra, Zanma Michaël John Compaoré, Guétawendé Job Wilfried Nassa, Aimé Parfait Korou Yaro, Bapouguini Raymond Gbangou, Raffaella Ravinetto, Halidou Tinto, Carine Dochez","doi":"10.1186/s12936-026-06006-8","DOIUrl":"10.1186/s12936-026-06006-8","url":null,"abstract":"<p><strong>Background: </strong>In February 2024, Burkina Faso introduced the malaria vaccine RTS,S/AS01 into its Expanded Programme on Immunisation (EPI). For vaccination to be successful, an important criterion is its acceptance by the population. Healthcare workers (HCWs) are among the primary sources of information for caregivers when deciding whether to vaccinate their children or not. This study aimed to assess HCWs' knowledge and acceptance of the new malaria vaccine (MV) in the Nanoro Health District and to identify factors associated with MV acceptance within this group.</p><p><strong>Methods: </strong>We conducted a cross-sectional study among HCWs from April to May 2025 in Nanoro (Burkina Faso), using an online questionnaire. All HCWs employed in the public or private health sectors of the Nanoro Health District at the time of data collection were eligible to participate, upon voluntary informed consent. The vaccine acceptance rate was expressed as the proportion of HCWs willing to vaccinate their children out of the total number of participants. Logistic regression was employed for both bivariate and multivariate analyses to test associations.</p><p><strong>Results: </strong>Two hundred fifty-seven (257) HCWs out of 340 eligible HCWs participated in the survey. The vaccine acceptance rate was 98.8%. Insufficient information about the vaccine was the primary reason for hesitancy. Twenty-two percent (22.6%) of the HCWs were unaware of the type of vaccine used in the district and had no knowledge of the vaccination schedule. More than half (58.0%) stated that they did not receive any training before the vaccine rollout. Willingness to recommend the vaccine and positive attitudes were associated with HCWs' willingness to vaccinate their children, although independent effects could not be confirmed. No links were found between vaccine acceptance and sociodemographic characteristics.</p><p><strong>Conclusions: </strong>Most HCWs were willing to vaccinate their children against malaria. However, few were hesitant due to insufficient information about the vaccine and more than one-fifth had limited knowledge about this specific vaccine. Training all HCWs on the MV (whether involved in EPI or not) and strengthening communication about it are essential to address concerns around the vaccine, and ensure sustained uptake in the community, thereby improving national vaccination coverage.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13560235/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148330945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Where did the nets go? Tracing long-lasting insecticidal net migration on Bioko Island.","authors":"Thomas C Stabler, Liyu A Teklemichael, Jeremias Nzamio Mba Eyono, Teobaldo Babo Dougan, Liberato Motobe Vas, Matilde Riloha Rivas, Wonder P Phiri, Dianna E B Hergott, Immo Kleinschmidt, David S Galick, Dave L Smith, Guillermo A García, Carlos A Guerra","doi":"10.1186/s12936-026-06019-3","DOIUrl":"10.1186/s12936-026-06019-3","url":null,"abstract":"<p><strong>Background: </strong>Long-lasting insecticidal nets (LLINs) are commonly distributed through mass distribution campaigns (MDCs). MDCs are often followed by substantial loss of LLINs, affecting coverage. Here, data from an MDC and a malaria indicator survey (MIS) on Bioko Island were used to characterize LLIN mobility.</p><p><strong>Methods: </strong>Between October 2014 and July 2015, an MDC reached most of the households of the island. All nets distributed were marked with a unique code corresponding to the community where they were distributed. An MIS conducted in August and September 2015 allowed to measure LLIN loss and mobility by verifying the number of existing nets and the community code. Multivariate models were used to identify factors associated with households with LLINs with mismatched codes. A source-sink analysis measuring risk gradient between the source community and the sink household was used to assess the overall effect of migrating nets.</p><p><strong>Results: </strong>The MIS revealed that of the 11,599 LLINs distributed to surveyed households, 7274 (62.7%) were observed during the MIS, indicating that 37.3% were no longer present. Among the 7,274 surviving nets, community codes were registered only for 3,413 (46.9%), and 551 of these (16.1%) revealed a mismatched code. Having open eaves was significantly associated with the presence of mismatched LLINs in households (aOR: 1.61; 95% CI 1.35-1.93, p < 0.001). The source sink analysis showed that while the majority of LLINs migrated from lower to higher risk areas (62.3%), almost a third migrated in the opposite direction.</p><p><strong>Conclusion: </strong>While redistribution had a positive impact on some communities by serving populations at higher risk of transmission, many households in high-risk areas lost their nets to areas with lower risk. This, coupled with the significant LLIN loss post-MDC, pointed to critical inefficiencies and prompted a shift in LLIN distribution strategy from MDC to demand-driven fixed distribution points.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13449829/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148330888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adherence to 14-day primaquine treatment for radical cure of Plasmodium vivax and mixed malaria patients treated at health centers in Yilmana Densa district, Ethiopia: a community-based cross-sectional study.","authors":"Eshetie Alelign Tsega, Ayenew Molla Lakew, Habtamu Alebachew Tegegne, Gizachew Abeza Getahun, Ejigu Gebeye Zeleke","doi":"10.1186/s12936-026-05982-1","DOIUrl":"10.1186/s12936-026-05982-1","url":null,"abstract":"<p><strong>Background: </strong>Primaquine is the right drug for the radical cure of malaria. The Ethiopian National malaria guideline recommends a 14-day course of primaquine for vivax and mixed malaria patients. Adherence to the full course of primaquine is crucial to achieve a radical cure. However, the recurrence of malaria is still high. Therefore, this study aimed to assess adherence status and identify factors affecting adherence to primaquine treatment among malaria patients treated at health centers in Yilmana Densa district, Ethiopia.</p><p><strong>Methods: </strong>A community-based cross-sectional study was conducted in Yilmana Densa district from December 15, 2024 to January 30, 2025. A total of 594 malaria patients were selected using systematic random sampling. Data were collected through house-to-house visits by using an interviewer-administered questionnaire and observation. Self-report, followed by a pill count, was used to ascertain adherence status. The data were entered with EpiData 4.7 and analyzed using Stata version 17. Binary logistic regression was used. Variables with a P-value < 0.25 in bivariable analysis were entered into multivariable analysis. Variables with a P-value < 0.05 were considered statistically significant.</p><p><strong>Results: </strong>Among the 594 study participants, 545 (91.8%) were interviewed. The overall adherence to primaquine treatment was 282 (51.7%), with a 95% confidence interval (CI) of 47.4% to 56.0%. Female sex (AOR = 1.64, 95%CI = 1.11-2.43), having knowledge that malaria can relapse (AOR = 1.69, 95%CI = 1.11-2.58), and a prior history of malaria infection (AOR = 1.67, 95%CI = 1.14-2.44) were positively associated with probably adherent. Whereas experiencing side effects was negatively associated (AOR = 0.49, 95%CI = 0.33-0.72).</p><p><strong>Conclusions: </strong>The primaquine treatment adherence status is low in the Yilmana Densa district. Being female, having knowledge that malaria can relapse, and having a prior malaria history were positively associated with adherence. Conversely, side effect has negatively associated. Hence, health education focusing on the risk of malaria relapse shall be promoted, giving due attention to males, and counselling about the expected side effects proactively.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13555863/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148317919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity of Plasmodium falciparum helical interspersed subtelomeric (phistb) gene in Tanzania and neighboring countries.","authors":"Ruth B Mbwambo, Dativa Pereus, Catherine Bakari, Ramadhan Moshi, Angelina J Kisambale, Rashid A Madebe, Seth D Misago, Celine I Mandara, Beatus Lyimo, Daniel Mbwambo, Sijenunu Aaron, Abdallah Lusasi, Samwel Lazaro, Gerald Juma, Benard W Kulohoma, Deus S Ishengoma","doi":"10.1186/s12936-026-06011-x","DOIUrl":"10.1186/s12936-026-06011-x","url":null,"abstract":"<p><strong>Background: </strong>Lysine-rich membrane associated Plasmodium helical interspersed subtelomeric gene (phistb) is a member of the phist family of genes which encodes exported proteins essential for the parasite's survival within infected red blood cells. Recent studies suggest the phistb gene as a promising malaria vaccine candidate, however, its genetic diversity remains understudied. This study assessed the genetic diversity of the phistb gene in regions of varying malaria transmission aiming to generate data and improve our understanding of this promising malaria vaccine candidate gene.</p><p><strong>Methods: </strong>Genomic data from 1472 Plasmodium falciparum samples from Tanzania, Kenya, Uganda, and Ethiopia were retrieved in variant Calling file format (VCF) format from the MalariaGEN Pf7 database. Variants were filtered to include only biallelic Single Nucleotide Polymorphism (SNPs) with Variant Quality Score Log- Odds (VQSLOD) > 1 and \"PASS\" status. Genetic diversity, differentiation, and selection signatures were analyzed using population genetics metrics.</p><p><strong>Results: </strong>After filtering, 1312 samples were retained. Wright's inbreeding coefficient (Fws) showed that 875 (66.7%) samples had monoclonal infections, with the highest proportion of monoclonal infections in Ethiopia (95.3%), followed by Tanzania (67.2%), Kenya (65.7%), and Uganda (50%). Among the 875 monoclonal samples, 88 haplotypes were identified, with Hap_1 (renamed PF3D7) and Hap_13 comprising 37.9 and 21.5 of the samples, respectively. Nucleotide and haplotype diversity were relatively higher in Kenya with 0.097, and 0.88 respectively, compared to the other study populations. The overall fixation index (Fst) was < 0.05, and Principal Component Analysis revealed no clear population sub-structure among countries. Negative Tajima's D values in Tanzania, Kenya, and Ethiopia indicated an excess of low-frequency alleles.</p><p><strong>Conclusion: </strong>This study reports low genetic diversity of the phistb gene in the four countries despite varying malaria transmission intensities among them, thus making it a suitable candidate gene for malaria vaccine. Further studies should be conducted to assess individual antibodies recognition of the phistb variants and the ability to elicit cross reactivity to further support its potential as a vaccine candidate.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13555929/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148317932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Associations between weather and Plasmodium vivax malaria in an Amazonian elimination setting: a distributed lag analysis from 2017 to 2024.","authors":"Gabriella Barratt Heitmann, Xue Wu, Anna T Nguyen, Astrid Altamirano-Quiroz, Sydney R Fine, Bryan Fernandez-Camacho, Antony Barja, Renato Cava, Verónica Soto-Calle, Hugo Rodriguez, Gabriel Carrasco-Escobar, Adam Bennett, Alejandro Llanos-Cuentas, Erin A Mordecai, Michelle S Hsiang, Jade Benjamin-Chung","doi":"10.1186/s12936-026-06010-y","DOIUrl":"10.1186/s12936-026-06010-y","url":null,"abstract":"<p><strong>Background: </strong>There is limited evidence regarding the association between weather and Plasmodium vivax (Pv), particulary in Latin America where Pv is the predominant malaria species and key challenge for countries to achieve malaria elimination.</p><p><strong>Methods: </strong>We analyzed the association between weather and Pv malaria incidence from 2017 to 2024 in 136 communities in the Peruvian Amazon. Monthly community-level incidence was calculated using Pv case data from Notiweb, the national epidemiological surveillance system, and population census data. Predictors included weekly minimum and maximum temperature and total weekly precipitation and were calculated using hourly weather from the climate dataset ERA5. Non-linear distributed lag models were fit using a lookback period of 2-16 weeks. Temperature models were adjusted for total precipitation; precipitation models were adjusted for maximum temperature. Sub-group analyses were conducted by community type (adjacent to river versus highway) and El Niño Southern Oscillation (ENSO) period.</p><p><strong>Results: </strong>Minimum temperature at the 90th percentile (23.7°C) was associated with 10% (95% CI 5-14%) higher malaria incidence compared to the 5th percentile (20.5°C) at a 7-week lag. Maximum temperature at the 90th percentile (33.7°C) was associated with 10% (95% CI 8-13%) higher malaria incidence compared to the 5th percentile (29.6°C) at a 9-week lag. Total weekly precipitation at the 90th percentile (1000 mm) was associated with 29% (95% CI 24-33%) higher malaria incidence compared to weeks with the 5th percentile (57 mm) at an 11-week lag. Incidence was higher and associations were stronger in communities adjacent to rivers versus highways. Malaria incidence was lower during El Niño periods, and there was evidence of interaction on the multiplicative scale for the association between incidence, all weather predictors, and ENSO period.</p><p><strong>Conclusions: </strong>Pv malaria incidence was positively associated with higher temperatures and precipitation in an elimination setting in Peru, particularly in riverine communities during non-El Niño years, with longer lag periods than previously reported for such associations. These findings can inform malaria elimination interventions to combat the long-lasting effects of weather on Pv transmission.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13551811/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148308656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anopheles gambiae biting behavior and malaria transmission risk in Simiw, a community located in the coastal forest zone of the Central Region of Ghana.","authors":"Evans Kofi Obboh, Abdul Rahim Mohammed Sabtiu, Isaac Kwame Sraku, Nana Aba Setorwu Eyeson, Emmanuel Kwesi Abu, Samuel Donkoh, Kwadwo Asamoah Kusi, Kwame Kumi Asare, Nicaise Ndam, Rachida Tahar, Festus Acquah, Yaw Asare Afrane, Anne Poinsignon, Linda Eva Amoah","doi":"10.1186/s12936-026-05961-6","DOIUrl":"10.1186/s12936-026-05961-6","url":null,"abstract":"<p><strong>Background: </strong>Changes in vector biology and behaviour resulting from interventions such as indoor residual spraying (IRS), long-lasting insecticidal nets (LLINs), and the use of insecticidal aerosol sprays, coils, and other mosquito control measures underscore the need for strengthened and regular vector surveillance. Understanding vector behaviour and species diversity is crucial for adapting interventions to achieve more effective and sustainable malaria control. This study examined malaria vector biting behaviour and transmission risk in Simiw, a community located in the coastal forest of Ghana's Central Region.</p><p><strong>Methods: </strong>Adult malaria vectors were collected using human landing catch (HLC) method during the dry and rainy season of 2021. Vector densities, biting patterns and entomological transmission indices of An. gambiae s.l. were evaluated. Molecular techniques were employed to identify vector species, detect Plasmodium falciparum infection, and analyze insecticide resistance genes.</p><p><strong>Results: </strong>A total of 4,173 mosquitoes from four different genera were collected during the sampling period, with a surprising higher abundance recorded in the dry season compared to the rainy season. Indoor collections of An. gambiae s.l. outnumbered outdoor collections in both seasons. An. coluzzii was the most prevalent species, making up 79.0% (678/858), followed by An. gambiae s.s. at 17.6%, hybrids of An. gambiae and An. coluzzii at 1.9% (16/858), and An. melas at 1.5% (13/858). The biting rate for An. gambiae s.l. peaked in the early morning hours between 04:00 and 05:00. The overall entomological inoculation rate (EIR) was calculated at 61.20 infective bites per person per year.</p><p><strong>Conclusion: </strong>The study found higher abundance and biting rates of An. gambiae s.l. during the dry season, with both the HBR and EIR being greater indoors than outdoors. The observed species diversity and transmission risk indices emphasize the importance of ongoing vector monitoring.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13551737/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148308722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasmodium-induced disruption of brain endothelial barrier integrity in vitro and in mice is prevented by inhibitors of farnesyltransferase.","authors":"Cláudia Gomes, Kelly A Crotty, Mariana C Borges Silva, Marilyn Vasquez, Lizeth Chicas, Isaac Salzano, Ana Rodriguez","doi":"10.1186/s12936-026-05981-2","DOIUrl":"10.1186/s12936-026-05981-2","url":null,"abstract":"<p><strong>Background: </strong>Cerebral malaria is a complication of Plasmodium falciparum infections where the integrity of the blood-brain barrier (BBB) is compromised, frequently leading to persistent neurological sequelae or death. The current treatment for cerebral malaria is based on rapid elimination of the parasite with intravenous anti-malarial drugs, but there is no adjunctive treatment that could address the loss of BBB integrity, potentially decreasing sequelae and improving the survival rate. Prenylation, a cellular process that incorporates isoprenoid lipids to specific protein sites, is known to regulate endothelial barrier integrity. Here we have studied the role of the isoprenoid farnesyl pyrophosphate (farnesyl-PP) and of different inhibitors of the enzymes that perform prenylation in endothelial cells to determine their effect on the endothelial barrier disruption induced by Plasmodium falciparum.</p><p><strong>Methods: </strong>An in vitro model using human brain microvascular endothelial cells (HBMECs) incubated with lysates of P. falciparum-infected red blood cells (iRBCs) and a mouse model of cerebral malaria were used to study the role of the two main prenylation enzymes, farnesyltransferase and geranylgeranyltransferase, in the regulation of endothelial barrier integrity in relation to cerebral malaria.</p><p><strong>Results: </strong>Addition of exogenous farnesyl-PP to HBMECs incubated with P. falciparum-iRBCs resulted in increased endothelial barrier disruption. Conversely, treatment with inhibitors of farnesyltransferase, but not of geranylgeranyltransferase, resulted in protection of barrier integrity against disruption induced by P. falciparum-iRBCs. Mice infected with Plasmodium berghei that were treated with the farnesyltransferase inhibitor tipifarnib presented delayed onset of cerebral malaria and higher survival rates.</p><p><strong>Conclusions: </strong>Inhibitors of farnesyltransferase protect human endothelial cell barrier integrity from disruption induced by P. falciparum in vitro and decrease mortality in mice with experimental cerebral malaria, indicating a role for farnesylation in the regulation of barrier integrity during cerebral malaria and identifying a potential drug target for the protection of the endothelium during severe malaria.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13551684/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148308667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beyond elimination; addressing challenges in maintaining the malaria elimination status in Suriname.","authors":"Stephen Vreden, Hedley Cairo, Gabriela Sanches, Anfernee Neus, Malti Adhin, Marthelise Eersel","doi":"10.1186/s12936-026-06004-w","DOIUrl":"10.1186/s12936-026-06004-w","url":null,"abstract":"<p><strong>Background: </strong>Suriname has been certified malaria-free by WHO on June 30th 2025. In the post-elimination era, malaria is still requiring full attention of the public health system. This is in particular due to the malaria burden in neighbouring countries and the intense migration across borders related to small scale artisanal gold mining, which poses a risk for re-establishment of malaria into the country.</p><p><strong>Analysis: </strong>Throughout the process of achieving certification of malaria elimination, the National Malaria Program implemented a range of strategies to maintain the zero transmission status. This manuscript describes and explains these strategies, highlighting the recent addition of individual targeted drug administration and presumptive antimalarial treatment. In the context of maintaining the elimination status of Suriname, the regional malaria situation is presented and the importance of a regional strategy in the ongoing fight against malaria addressed.</p><p><strong>Conclusion: </strong>Suriname is extremely susceptible for re-establishment of malaria. The National Malaria Elimination Task Force implemented innovative strategies, adapted to the dynamics of malaria importation. Next to these national actions, it is pivotal that the malaria situation in the Guiana Shield is addressed with a regional effort.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13548703/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148302395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Behavioral patterns of humans and Anopheles arabiensis reveal outdoor malaria transmission risk at Pemba Island, Zanzibar.","authors":"Ali O Ali, Bakar O Khatib, Khadija F Ali, Fatma A Massoud, Talib S Khatib, Moza K Rashid, Steven Gowelo, Shija J Shija, Kali A Omar, Makame M Kombo, Joseph Joachim Joseph, Nicodem J Govella, Neil F Lobo","doi":"10.1186/s12936-026-06017-5","DOIUrl":"10.1186/s12936-026-06017-5","url":null,"abstract":"<p><strong>Background: </strong>Zanzibar has achieved and sustained very low malaria prevalence through high coverage of indoor residual spraying (IRS) and insecticide-treated nets (ITNs). However, residual transmission persists, particularly on Pemba Island. Increasing evidence suggests that the predominance of exophagic vectors and outdoor human activity patterns may reduce the effectiveness of indoor-focused interventions. This study aimed to quantify malaria transmission risk arising from the interaction between human behavior and mosquito biting activity indoors and outdoors on Pemba Island.</p><p><strong>Methods: </strong>From February 2024 to January 2025, adult malaria vectors were collected using human landing catches (HLCs) indoors and outdoors at sentinel sites across four districts of Pemba Island. Concurrent human behavior observations (HBOs) were conducted hourly to record location, activity, age, sex, and ITNs use within households. Human biting rates (HBRs) and behavior-adjusted biting rates were calculated to estimate human behavior-adjusted exposure and identify protection gaps by age and sex.</p><p><strong>Results: </strong>A total of 981 Anopheles mosquitoes were collected, of which 98% of An. gambiae s.l. were An. arabiensis. Mosquito collection was significantly higher outdoor than indoor (Relative rate = 4.37, 95% CI 3.61-5.29, p < 0.0001). Most bites occurred outdoors (≈82%), with peak biting in the early evening (19:00-20:00 h) for both indoor and outdoor. Across the population, approximately 85% of unprotected exposure occurred outdoors while individuals were awake. Children under five experienced relatively more indoor exposure, while school-aged children and adults were predominantly exposed outdoors. Men experienced higher outdoor exposure than women, whereas women had greater indoor exposure while awake. ITNs provided substantial protection for young children but prevented a declining proportion of exposure with increasing age, leaving substantial residual risk across all groups.</p><p><strong>Conclusions: </strong>Residual malaria transmission on Pemba Island is driven primarily by outdoor exposure linked to human behaviour patterns and exophagic An. arabiensis. While ITNs continue to protect young children indoors, they do not address most exposure among older children and adults. Malaria elimination efforts in Zanzibar will require complementary interventions that target outdoor transmission and behavioral risk, alongside existing indoor-focused strategies.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13536781/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148295816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of flow cytometry bead-based opsonophagocytic assays to dissect cell-mediated functional antibody responses to malaria vaccines.","authors":"Daan J van den Brink, Elena Boero, Katie Ewer, Omar Rossi","doi":"10.1186/s12936-026-06008-6","DOIUrl":"10.1186/s12936-026-06008-6","url":null,"abstract":"<p><strong>Background: </strong>Malaria remains a major global health burden. Vaccines targeting the Circumsporozoite protein represent a significant advancement in malaria control and have demonstrated meaningful public health impact. However, no validated correlate of protection has yet been established, making it critical to assess antibody functionality alongside antigen-specific antibody quantitation to evaluate vaccine candidates. Antibody-dependent phagocytosis is one such mechanism that contributes to parasite clearance, which can be modelled using cell lines. While THP-1 (monocyte-like) assays have been described, HL-60 (neutrophil-like) models are less established in the malaria field. Here, we aimed to develop and characterize a PfCSP repeat region (NANP6) bead-based opsonophagocytic assay using differentiated HL-60 cells, to adapt a THP-1 assay, and to assess IgG subclass- and FcγR-dependent differences between these in vitro models. Ultimately, our goal is to demonstrate the potential application of these assays for exploratory assessment of human clinical samples.</p><p><strong>Methods: </strong>Fluorescent NANP6-coated beads were opsonized with recombinant IgG1-2-3-4 monoclonal antibodies (identical binding domain, different Fc) or human sera from an RTS, S/AS01E trial. Opsonized beads were incubated with model effector cells, phagocytosis was quantified by flow cytometry, and EC50 values were derived using four-parameter logistic regression. FcγR-blocking experiments and assay performance (precision, dilution linearity, sensitivity) were evaluated.</p><p><strong>Results: </strong>Both assays discriminated phagocytic potency across IgG subclasses, revealing that FcγR dependence differs by subclass and between the two cell models. Both assays were successfully adapted to human sera, demonstrating robust performance with high precision, strong dilution linearity, and high sensitivity across samples with varying anti-CSP antibody levels. These characteristics support their suitability for reproducible assessment of functional antibody responses in clinical samples.</p><p><strong>Conclusion: </strong>Two opsonophagocytic assays recapitulating monocyte-like and neutrophil-like effector pathways were developed and characterized. Both demonstrated precise, sensitive, and quantitative measurement of antibody-dependent phagocytosis in human sera, while capturing distinct functional differences between the models, supporting their use as exploratory tools to evaluate functional antibody responses in clinical samples.</p>","PeriodicalId":18317,"journal":{"name":"Malaria Journal","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13540815/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148295774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}