RESUMO

In both humans and mice, natural killer (NK) cells are important lymphocytes of the innate immune system. They are often considered pro-inflammatory effector cells but may also have a regulatory or pro-resolving function by switching their cytokine profile towards the production of anti-inflammatory cytokines, including interleukin-10 (IL-10) and transforming growth factor-ß, and by killing pro-inflammatory immune cells. Here, the role of NK cells in the resolution of malaria lung pathology was studied. Malaria complications, such as malaria-associated acute respiratory distress syndrome (MA-ARDS), are often lethal despite the rapid and efficient killing of Plasmodium parasites with antimalarial drugs. Hence, studying the resolution and healing mechanisms involved in the recovery from these complications could be useful to develop adjunctive treatments. Treatment of Plasmodium berghei NK65-infected C57BL/6 mice with a combination of artesunate and chloroquine starting at the appearance of symptoms was used as a model to study the resolution of MA-ARDS. The role of NK cells was studied using anti-NK1.1 depletion antibodies and NK cell-deficient mice. Using both methods, NK cells were found to be dispensable in the development of MA-ARDS, as shown previously. In contrast, NK cells were crucial in the initiation of resolution upon antimalarial treatment, as survival was significantly decreased in the absence of NK cells. Considerably increased IL-10 expression by NK cells suggested an anti-inflammatory and pro-resolving phenotype. Despite the increase in Il10 expression in the NK cells, inhibition of the IL-10/IL-10R axis using anti-IL10R antibodies had no effect on the resolution for MA-ARDS, suggesting that the pro-resolving effect of NK cells cannot solely be attributed to their IL-10 production. In conclusion, NK cells contribute to the resolution of experimental MA-ARDS.

Assuntos

Antimaláricos , Modelos Animais de Doenças , Células Matadoras Naturais , Malária , Camundongos Endogâmicos C57BL , Plasmodium berghei , Síndrome do Desconforto Respiratório , Animais , Células Matadoras Naturais/imunologia , Antimaláricos/uso terapêutico , Camundongos , Malária/imunologia , Malária/tratamento farmacológico , Síndrome do Desconforto Respiratório/imunologia , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/etiologia , Plasmodium berghei/imunologia , Camundongos Knockout , Interleucina-10/metabolismo , Cloroquina/uso terapêutico , Cloroquina/farmacologia , Pulmão/imunologia , Pulmão/parasitologia , Artesunato/uso terapêutico , Artesunato/farmacologia

RESUMO

BACKGROUND: Malaria is a major public health issue in Guinea and care-seeking behaviour is dominated by self-medication and delayed access to appropriate care. However early and appropriate care-seeking are essential to control and reduce complicate forms and mortality, particularly for the most vulnerable. This study was conducted to analyse the diagnostic pathway, and the factors associated with early and appropriate care-seeking for malaria patients in the Republic of Guinea. METHODS: A cross-sectional study was carried out between December 2022 to March 2023 in nine health districts within health facilities and at community level. The study population was confirmed malaria patients with RDT or microscopy. Kroeger's conceptual framework was used to design the questionnaire. Conventional recourse was defined as using a healthcare facility or community services, early and appropriate care-seeking was defined as within 24 h of symptom onset in a conventional recourse, and care pathway as the sequence of recourses followed by each patient. Sankey alluvial plots were used to represent patients' diagnostic pathways, and logistic regression to identify factors associated with early and appropriate care-seeking. RESULTS: A total of 3300 malaria patients were studied, of which 1632 (49.45%) were female and 1132 (34.30%) were under 5 years of age, with a median age of 23 months. At the time of the survey, 1337 (40.52%), 1423 (43.12%), and 437 (13.85%) of patients were respectively in their first, second and third recourse. A total of 2002 (60.67%) patients had sought care from a conventional recourse as a first line. Of all patients, 1757 (53.25%) had sought care within 24 h, while 28.55% had sought early and appropriate care. In the initial stages of treatment, self-medication was the most common approach, used by 1214 (37.30%). Patients from the health districts of Boffa (Lower Guinea, coastal region) OR = 0.48 95% CI 0.33-0.70, Dabola (Upper Guinea, savanna region) OR = 0.43 95% CI 0.30-0.63 and Labe (Middle Guinea, mountain region) OR = 0.63 CI 95% 0.43-0.91 (p < 0.05) were more likely to delay appropriate care-seeking, when compared to those in Dixinn, (Conakry). However, the under 5-year-old group OR = 1.55 95% CI 1.30-1.85 (p < 0.001) and the availability of a stable monthly household income OR = 4.98 95% CI 3.03, 8.27 (p < 0.001) were positively associated with early and appropriate care seeking. CONCLUSION: A low rate of early and appropriate care-seeking was observed. Patients sought care through multiple means, often resulting in a delay in adequate management. The results show the need to deploy strategies adapted to the needs of communities.

Assuntos

Malária , Aceitação pelo Paciente de Cuidados de Saúde , Estudos Transversais , Guiné , Feminino , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adulto , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Pré-Escolar , Criança , Lactente , Idoso

RESUMO

BACKGROUND: Malaria remains an important public health problem, particularly in sub-Saharan Africa. In Rwanda, where malaria ranks among the leading causes of mortality and morbidity, disease transmission is influenced by climatic factors. However, there is a paucity of studies investigating the link between climate change and malaria dynamics, which hinders the development of effective national malaria response strategies. Addressing this critical gap, this study analyses how climatic factors influence malaria transmission across Rwanda, thereby informing tailored interventions and enhancing disease management frameworks. METHODS: The study analysed the potential impact of temperature and cumulative rainfall on malaria incidence in Rwanda from 2012 to 2021 using meteorological data from the Rwanda Meteorological Agency and malaria case records from the Rwanda Health Management and Information System. The analysis was performed in two stages. First, district-specific generalized linear models with a quasi-Poisson distribution were applied, which were enhanced by distributed lag non-linear models to explore non-linear and lagged effects. Second, random effects multivariate meta-analysis was employed to pool the estimates and to refine them through best linear unbiased predictions. RESULTS: A 1-month lag with specific temperature and rainfall thresholds influenced malaria incidence across Rwanda. Average temperature of 18.5 °C was associated with higher malaria risk, while temperature above 23.9 °C reduced the risk. Rainfall demonstrated a dual effect on malaria risk: conditions of low (below 73 mm per month) and high (above 223 mm per month) precipitation correlated with lower risk, while moderate rainfall (87 to 223 mm per month) correlated with higher risk. Seasonal patterns showed increased malaria risk during the major rainy season, while the short dry season presented lower risk. CONCLUSION: The study underscores the influence of temperature and rainfall on malaria transmission in Rwanda and calls for tailored interventions that are specific to location and season. The findings are crucial for informing policy that enhance preparedness and contribute to malaria elimination efforts. Future research should explore additional ecological and socioeconomic factors and their differential contribution to malaria transmission.

Assuntos

Mudança Climática , Malária , Chuva , Temperatura , Ruanda/epidemiologia , Malária/epidemiologia , Malária/transmissão , Incidência , Humanos , Estações do Ano , Clima

RESUMO

BACKGROUND: Ongoing conflict between multiple armed groups, including pastoralist herders in the Central African Republic (CAR) causes frequent population displacements, food insecurity and scarcity of healthcare services. The inaccessibility and insecurity of many areas of CAR limit data collection and assessments from national nutritional surveys. Community health workers (CHWs) trained by an international non-governmental organisation, The MENTOR Initiative, deliver basic healthcare to children under 5 years old living in hard-to-reach and conflict-affected areas in eight subprefectures of north-west CAR. Their nutritional status and its associations with geography, malaria, season and conflict are unknown. METHODS: CHW monthly records (October 2015-August 2021), Armed Conflict Location and Event Data project conflict data and The World Bank Group meteorological data for eight subprefectures of north-west CAR were analysed. Associations between counts of global acute malnutrition (GAM) assessed by mid-upper arm circumference and malaria, season and conflict were investigated using negative binomial regression. RESULTS: Of the 457,325 consultations with children aged 6-59 months, 6.2% and 0.4% were classified as moderately or severely malnourished, respectively. The negative binomial model demonstrated differences in counts of GAM by subprefecture. Counts of GAM were positively associated with the case rate of severe malaria (IRR = 1.045; 95% CI: 1.04-1.06) and the rainy season (July-September) (IRR = 1.10; 95% CI: 1.03-1.17). Conflict events coded as Battles in ACLED were associated with lower counts of GAM (IRR = 0.78; 95% CI: 0.62-0.97). CONCLUSIONS: This analysis shows geographical differences in levels of malnutrition in north-west CAR and demonstrates clear associations between malnutrition, season and malaria. It provides evidence that levels of GAM may be underestimated in north-west CAR in areas experiencing conflict. These findings highlight the need for targeted nutritional support to reach children most at risk of malnutrition. CHWs are a proven effective means of delivering essential primary healthcare services in hard-to-reach, conflict-affected areas.

Assuntos

Malária , Estações do Ano , Humanos , Malária/epidemiologia , Pré-Escolar , Lactente , República Centro-Africana/epidemiologia , Incidência , Masculino , Feminino , Desnutrição/epidemiologia , Conflitos Armados , Geografia , Estado Nutricional

RESUMO

Maternal health remains a global priority, with particular emphasis on combating infectious diseases such as HIV and malaria during pregnancy. Despite significant progress in prevention and treatment efforts, both HIV and malaria continue to pose significant risks to maternal and fetal well-being, particularly in resource-limited settings. The prevention of mother-to-child transmission (PMTCT) programs for HIV and intermittent preventive treatment (IPTp) for malaria represent cornerstone strategies in mitigating the impact of these infections on pregnancy outcomes. PMTCT programs focus on early HIV diagnosis, antiretroviral therapy initiation, and promoting safe infant feeding practices to reduce the risk of mother-to-child transmission. Similarly, IPTp involves the administration of antimalarial medication to pregnant women in malaria-endemic regions to prevent maternal and fetal complications associated with malaria infection. Integration of HIV and malaria prevention and treatment services within existing maternal and child health programs is crucial for maximizing impact and minimizing healthcare system strain. Strengthening health systems, improving access to antenatal care services, and enhancing community engagement are essential components of comprehensive maternal health strategies. Furthermore, promoting awareness, education, and empowerment of pregnant women and communities are vital in fostering health-seeking behaviors and adherence to preventive measures against HIV and malaria. In conclusion, protecting maternal health from the dual threat of HIV and malaria requires a multifaceted approach that encompasses prevention, screening, treatment, and community engagement.

Assuntos

Infecções por HIV , Transmissão Vertical de Doenças Infecciosas , Malária , Complicações Infecciosas na Gravidez , Humanos , Gravidez , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Infecções por HIV/tratamento farmacológico , Malária/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Saúde Materna , Antimaláricos/uso terapêutico , Cuidado Pré-Natal/métodos

RESUMO

Mosquito-borne diseases, such as malaria, dengue, and Zika, pose major public health challenges globally, affecting millions of people. The growing resistance of mosquito populations to synthetic insecticides underscores the critical need for effective and environmentally friendly larvicides. Although chemical pesticides can initially be effective, they often lead to negative environmental consequences and health hazards for non-target species, including humans. This study aimed to evaluate the larvicidal effects of Trachyspermum ammi essential oil and Delphinium speciosum extract on the larvae of three major mosquito species: Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Mosquito larvae of Ae. aegypti, An. stephensi, and Cx. quinquefasciatus were reared under controlled laboratory conditions. The larvicidal activity of T. ammi essential oil and D. speciosum extract was evaluated through standard bioassays, using various concentrations of essential oils (10, 20, 40, 80, and 160 ppm) and extracts (160, 320, 640, 1280, and 2560 ppm) to determine the lethal concentration (LC50) values after 24 h of exposure. Fresh plant materials were collected, with the essential oil extracted via hydro-distillation, and the extract prepared using methanol solvent extraction. The chemical composition of T. ammi essential oil was examined using gas chromatography-mass spectrometry (GC-MS). Additionally, the preliminary analysis of the chemical compounds in D. speciosum extract was carried out using thin layer chromatography (TLC) and nuclear magnetic resonance spectroscopy (NMR) techniques. The results indicated that the essential oil of T. ammi exhibited more effective larvicidal activity compared to the D. speciosum extract. Specifically, the essential oil demonstrated LC50 values of 18 ppm for Cx. quinquefasciatus and 19 ppm for Ae. aegypti. In contrast, the D. speciosum extract showed the strongest larvicidal effect against An. stephensi, with an LC50 of 517 ppm. Concentrations of 40 ppm of the essential oil and 1280 ppm of the extract resulted in 100% mortality across all three species. Both the essential oil of T. ammi and the D. speciosum extract exhibited concentration-dependent larvicidal activity, and these results were statistically significant (p < 0.001) compared to the no-treatment group. GC-MS analysis revealed thymol (88.95%), o-cymen-5-ol (4.11%), and γ-terpinene (2.10%) as the major constituents of the T. ammi essential oil. Additionally, TLC verified the presence of alkaloids in both chloroform and methanolic extracts. Proton NMR identified a diterpene structure for these alkaloids. These findings suggest that T. ammi essential oil is a promising candidate for natural mosquito control strategies. Given its efficacy, further research is warranted to explore its potential in integrated vector management programs.

Assuntos

Delphinium , Inseticidas , Larva , Mosquitos Vetores , Óleos Voláteis , Extratos Vegetais , Animais , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Larva/efeitos dos fármacos , Mosquitos Vetores/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Inseticidas/farmacologia , Inseticidas/química , Delphinium/química , Aedes/efeitos dos fármacos , Dengue , Malária/prevenção & controle , Anopheles/efeitos dos fármacos , Filariose , Culex/efeitos dos fármacos , Controle de Mosquitos/métodos

RESUMO

BACKGROUND: In Malaysia, despite a decline in cases, malaria remains a major public health concern, especially among the vulnerable indigenous people (i.e. Orang Asli) in remote areas. Effective preventive and control measures require an evidence-based understanding of their knowledge, attitudes, and practices (KAP) regarding malaria. This study aimed to evaluate the KAP regarding malaria in an indigenous settlement in Peninsular Malaysia. METHODS: A household-based cross-sectional study was conducted in March 2024 in six Semai sub-ethnic indigenous villages in Pos Lenjang, Kuala Lipis, Pahang. A structured questionnaire was administered to randomly selected individuals (≥ 12 years old) to collect data on sociodemographic characteristics and KAP. Data were analysed using descriptive statistics and predictors of KAP were determined using logistic regression. A p-value less than 0.05 was considered statistically significant. RESULTS: A total of 267 individuals from 160 households were interviewed. Nearly half had good knowledge (49.4%) and positive attitudes (54.3%) towards malaria, with high practice scores for prevention and control (83.1%). Multivariate logistic regression analysis showed higher odds of good knowledge in those aged 40-59 years (adjusted odd ratio [aOR] = 6.90, p = 0.034), with primary (aOR = 2.67, p = 0.015) or secondary education (aOR = 2.75, p = 0.019), and with previous malaria history (aOR = 5.14, p < 0.001). Higher odds of a good attitude were found in those with secondary education (aOR = 4.05, p < 0.001) and previous malaria history (aOR = 2.74, p = 0.017). Lower odds were observed for the unemployed (aOR = 0.25, p = 0.018) and those collecting forest products (aOR = 0.25, p = 0.049) for attitude and practice, respectively. DISCUSSION: The overall practice level on malaria prevention was high among the Semai Orang Asli in Pahang. However, to ensure sustainability, the low levels of knowledge and attitude regarding malaria must be strengthened through increased health education and continuous community engagement.

Assuntos

Conhecimentos, Atitudes e Prática em Saúde , Malária , Humanos , Malásia , Estudos Transversais , Masculino , Feminino , Malária/prevenção & controle , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Povos Indígenas/estatística & dados numéricos , Povos Indígenas/psicologia , Idoso , Inquéritos e Questionários

RESUMO

BACKGROUND: Malaria in pregnancy (MiP) is a condition that can be prevented by using intermittent preventive treatment using Sulfadoxine-pyrimethamine. However, despite all the effort to reduce the consequences of MiP for the woman, the unborn child, and the neonate, the knowledge of Intermittent Preventive Treatment of Malaria in pregnancy using sulfadoxine-pyrimethamine (IPTp-SP) is low in most malaria-endemic countries, including Ghana. Thus, the need to examine knowledge, and attitude of service users of intermittent preventive treatment of malaria in pregnancy using sulfadoxine-pyrimethamine. METHODS: The study was a cross-sectional survey of two selected districts in the Volta Region of Ghana. The study participants were randomly selected from communities within Nkwanta North and North Tongu District. In all a total of 438 mothers who have delivered in the past 24 months were selected for the study. The women were interviewed using a structured questionnaire and the bivariate and multivariable logistic regression results presented in tables. RESULTS: The level of knowledge, and attitude were reported as 45.9% and 58.9% respectively. Knowledge of the service user is determined by the level of education of the women. The attitude of the service user is determined by making 4-7 visits during ANC, Gestational age at booking for ANC is 4-7 weeks, income level between 100 to 999, partner educational level above Middle/JHS/JSS, and age of a partner is above 40 years. CONCLUSION: The findings from the present studies highlighted important factor such as number of antenatal visits that affect both knowledge of services and attitude to use IPTp-SP. Therefore, a community-based health promotion programmes to help to increase knowledges and improved attitude on timely and regular antenatal attendance to promote the benefit of IPTp-SP should be encouraged.

Assuntos

Antimaláricos , Combinação de Medicamentos , Conhecimentos, Atitudes e Prática em Saúde , Malária , Complicações Parasitárias na Gravidez , Pirimetamina , Sulfadoxina , Humanos , Feminino , Gana/epidemiologia , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Gravidez , Adulto , Malária/prevenção & controle , Malária/tratamento farmacológico , Malária/epidemiologia , Antimaláricos/uso terapêutico , Estudos Transversais , Complicações Parasitárias na Gravidez/prevenção & controle , Complicações Parasitárias na Gravidez/tratamento farmacológico , Adulto Jovem , Adolescente , Inquéritos e Questionários

RESUMO

BACKGROUND: Malaria is the parasitic disease with the highest morbimortality worldwide. The World Health Organization (WHO) estimates that there were approximately 249 million cases in 2022, of which 3.4% were in Angola. Diagnosis is based on parasite identification by microscopy examination, antigen detection, and/or molecular tests, such as polymerase chain reaction (PCR). This study aimed to evaluate the usefulness of real-time PCR as a diagnostic method for malaria in an endemic area (Cubal, Angola). METHODS: A cross-sectional study was carried out at the Hospital Nossa Senhora da Paz in Cubal, Angola, including 200 patients who consulted for febrile syndrome between May and July 2022. From each patient, a capillary blood sample was obtained by finger prick for malaria field diagnosis [microscopy and rapid diagnostic test (RDT)] and venous blood sample for real-time PCR performed at the Hospital Universitario Vall d'Hebron in Barcelona, Spain. Any participant with a positive result from at least one of these three methods was diagnosed with malaria. RESULTS: Of the 200 participants included, 54% were female and the median age was 7 years. Malaria was diagnosed by at least one of the three techniques (microscopy, RDT, and/or real-time PCR) in 58% of the participants, with RDT having the highest percentage of positivity (49%), followed by real-time PCR (39.5%) and microscopy (33.5%). Of the 61 discordant samples, 4 were only positive by microscopy, 13 by real-time PCR, and 26 by RDT. Plasmodium falciparum was the most frequent species detected (90.63%), followed by P. malariae (17.19%) and P. ovale (9.38%). Coinfections were detected in ten participants (15.63%): six (60%) were caused by P. falciparum and P. malariae, three (30%) by P. falciparum and P. ovale, and one (10%) triple infection with these three species. In addition, it was observed that P. falciparum and P. malariae coinfection significantly increased the parasite density of the latter. CONCLUSIONS: RDT was the technique with the highest positivity rate, followed by real-time PCR and microscopy. The results of the real-time PCR may have been underestimated due to suboptimal storage conditions during the transportation of the DNA eluates. However, real-time PCR techniques have an important role in the surveillance of circulating Plasmodium species, given the epidemiological importance of the increase in non-falciparum species in the country, and can provide an estimate of the intensity of infection.

Assuntos

Febre , Malária , Plasmodium , Reação em Cadeia da Polimerase em Tempo Real , Humanos , Angola/epidemiologia , Feminino , Reação em Cadeia da Polimerase em Tempo Real/métodos , Masculino , Estudos Transversais , Malária/diagnóstico , Malária/parasitologia , Malária/epidemiologia , Criança , Febre/parasitologia , Pré-Escolar , Plasmodium/isolamento & purificação , Plasmodium/genética , Plasmodium/classificação , Adolescente , Adulto , Microscopia/métodos , Adulto Jovem , Lactente , Sensibilidade e Especificidade , Pessoa de Meia-Idade , Plasmodium falciparum/genética , Plasmodium falciparum/isolamento & purificação , Testes Diagnósticos de Rotina/métodos

Assuntos

Coinfecção , Hospitais Universitários , Malária , Febre Tifoide , Nigéria/epidemiologia , Humanos , Febre Tifoide/epidemiologia , Febre Tifoide/complicações , Estudos Retrospectivos , Coinfecção/epidemiologia , Coinfecção/parasitologia , Masculino , Feminino , Adulto , Hospitais Universitários/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Adulto Jovem , Pessoa de Meia-Idade , Lactente , Idoso

RESUMO

BACKGROUND: A quasi-experimental comparative trial will be designed in Burkina Faso. The study will compare the use and preferences for two groups types of insecticide-treated nets textile: polyester-based and polyethylene-based, according to their use and preferences in selected health districts. These health districts will be selected in three eco-climate zones (Sahelian, dry savannah and wet savannah) in the country. These findings will inform decisions on future net procurements for national malaria control programme in 2025. METHODS: Quantitative surveys and qualitative data collection will be carried out to gather information on the type of net textile most commonly used and preferred by the community. They will be performed between the end of the dry season and the early rainy season. The quantitative surveys involved household interviews with households and individuals' questionnaires, while the qualitative data collection involved in-depth individual interviews and focus group discussions to explore and clarify some key evaluation criteria. A total of 9450 insecticide-treated nets were surveyed for quantitative survey purposes. For the qualitative study, 48 in-depth individual interviews and 12 focus group discussions were carried out. A mixed model approach combining the results from quantitative surveys and qualitative studies will be used for decision-making on the type of insecticide-treated net preference. CONCLUSION: This methodological approach will be used by the National Malaria Control Programme to conduct this study on determinants of net use in Burkina Faso in order to provide robust evidence across diverse settings. This mixed-methods approach for data collection and analysis could be used in other countries to provide evidence that would help to increase the uptake of insecticide-treated nets, the main vector control tool in Africa.

Assuntos

Características da Família , Mosquiteiros Tratados com Inseticida , Malária , Controle de Mosquitos , Burkina Faso , Malária/prevenção & controle , Humanos , Controle de Mosquitos/métodos , Controle de Mosquitos/estatística & dados numéricos , Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Polietileno , Poliésteres , Tomada de Decisões , Têxteis , Inquéritos e Questionários

RESUMO

This study examined the effect of women's educational level on their perceptions regarding the deadliness of malaria in children. The regression results revealed that women with primary education did not differ statistically from the reference category (i.e. women with no education) in terms of their likelihood of perceiving malaria as a deadly disease in children. In contrast, women with secondary education were 4.3 percentage points more likely to perceive malaria as a deadly disease compared to the reference category. Similarly, women with higher education were 8 percentage points more likely to perceive malaria as a deadly disease compared to the reference category. These results highlight the crucial role of women's education in shaping their perceptions of disease in children, which also has implications for child health outcomes.

Assuntos

Escolaridade , Conhecimentos, Atitudes e Prática em Saúde , Malária , Humanos , Nigéria , Feminino , Adulto , Criança , Adolescente , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem

RESUMO

BACKGROUND: Anopheles melas is an understudied malaria vector with a potential role in malaria transmission on the Bijagós Archipelago of Guinea-Bissau. This study presents the first whole-genome sequencing and population genetic analysis for this species from the Bijagós. To our knowledge, this also represents the largest population genetic analysis using WGS data from non-pooled An. melas mosquitoes. METHODS: WGS was conducted for 30 individual An. melas collected during the peak malaria transmission season in 2019 from six different islands on the Bijagós Archipelago. Bioinformatics tools were used to investigate the population structure and prevalence of insecticide resistance markers in this mosquito population. RESULTS: Insecticide resistance mutations associated with pyrethroid resistance in Anopheles gambiae s.s. from the Bijagós were absent in the An. melas population, and no signatures of selective sweeps were identified in insecticide resistance-associated genes. Analysis of structural variants identified a large duplication encompassing the cytochrome-P450 gene cyp9k1. Phylogenetic analysis using publicly available mitochondrial genomes indicated that An. melas from the Bijagós split into two phylogenetic groups because of differentiation on the mitochondrial genome attributed to the cytochrome C oxidase subunits COX I and COX II and the NADH dehydrogenase subunits 1, 4, 4L and 5. CONCLUSIONS: This study identified an absence of insecticide-resistant SNPs common to An. gambiae in the An. melas population, but did identify structural variation over insecticide resistance-associated genes. Furthermore, this study presents novel insights into the population structure of this malaria vector using WGS analysis. Additional studies are required to further understand the role of this vector in malaria transmission.

Assuntos

Anopheles , Resistência a Inseticidas , Malária , Mosquitos Vetores , Filogenia , Sequenciamento Completo do Genoma , Animais , Resistência a Inseticidas/genética , Anopheles/genética , Anopheles/efeitos dos fármacos , Guiné-Bissau/epidemiologia , Mosquitos Vetores/genética , Mosquitos Vetores/efeitos dos fármacos , Malária/transmissão , Malária/epidemiologia , Inseticidas/farmacologia , Piretrinas/farmacologia , Genoma Mitocondrial/genética , Feminino

RESUMO

Trove of data-mining resources on malaria and other killers will need donations to stay alive.

Assuntos

Bases de Dados Factuais , Malária , National Institutes of Health (U.S.) , Parasitologia , Humanos , Mineração de Dados , Bases de Dados Factuais/economia , Financiamento Governamental , Malária/economia , National Institutes of Health (U.S.)/economia , Parasitologia/economia , Apoio à Pesquisa como Assunto , Estados Unidos

Assuntos

Antimaláricos , Malária , Complicações Parasitárias na Gravidez , Humanos , Gravidez , Feminino , Malária/prevenção & controle , Antimaláricos/uso terapêutico , Complicações Parasitárias na Gravidez/prevenção & controle , Disseminação de Informação/métodos , Complicações Infecciosas na Gravidez/prevenção & controle

RESUMO

Australian Defence Force (ADF) personnel train and operate in malarious regions that include neighboring countries with high burden and species with latent hepatic parasites.1 We summarized longitudinal malaria case data, following a prior 10-year period review to 2007.2 Malaria case entries within the ADF Malaria and Infectious Diseases Institute (ADFMIDI)-managed Central Malaria Register (CMR) were examined. Data from cases confirmed between January 1, 2008 through December 31, 2022 were analyzed. Sixty ADF members were diagnosed with malaria, including 1 with a mixed Plasmodium falciparum and P. vivax infection. Of 61 malaria infections, 69% (42 of 61) were P. vivax. P. vivax infection resulted in delayed initial case presentation (more than 4 weeks after exposure) in at least 36% (15 of 42) of cases, and 5 personnel experienced further relapse. Most P. vivax infections were acquired in the U.S. Indo-Pacific Command (INDOPACOM) and P. falciparum in the U.S. Africa Command (AFRICOM) regions. The ADF experienced ongoing reduced malaria case incidence following high rates in the early 2000s. Maintenance of prophylactic vigilance, both for eradicating dormant hypnozoites and preventing P. vivax relapse, remains important, however.

Assuntos

Malária Falciparum , Malária Vivax , Militares , Humanos , Militares/estatística & dados numéricos , Austrália/epidemiologia , Masculino , Feminino , Adulto , Malária Vivax/epidemiologia , Malária Falciparum/epidemiologia , Adulto Jovem , Incidência , Pessoa de Meia-Idade , Plasmodium vivax/isolamento & purificação , Malária/epidemiologia , Plasmodium falciparum/isolamento & purificação , Sistema de Registros

RESUMO

BACKGROUND: Severe malaria can cause respiratory symptoms, which may lead to malaria-acute lung injury (MA-ALI) due to inflammation and damage to the blood-gas barrier. Patients with severe malaria also often present thrombocytopenia, and the use of acetylsalicylic acid (ASA), a commonly used non-steroidal anti-inflammatory drug with immunomodulatory and antiplatelet effects, may pose a risk in regions where malaria is endemic. Thus, this study aimed to investigate the systemic impact of ASA and dihydroartemisinin (DHA) on ALI induced in mice by Plasmodium berghei NK65 (PbNK65). METHODS: C57BL/6 mice were randomly divided into control (C) and PbNK65 infected groups and were inoculated with uninfected or 104 infected erythrocytes, respectively. Then, the animals were treated with DHA (3 mg/kg) or vehicle (DMSO) at the 8-day post-infection (dpi) for 7 days and with ASA (100 mg/kg, single dose), and analyses were performed at 9 or 15 dpi. Lung mechanics were performed, and lungs were collected for oedema evaluation and histological analyses. RESULTS: PbNK65 infection led to lung oedema, as well as increased lung static elastance (Est, L), resistive (ΔP1, L) and viscoelastic (ΔP2, L) pressures, percentage of mononuclear cells, inflammatory infiltrate, hemorrhage, alveolar oedema, and alveolar thickening septum at 9 dpi. Mice that received DHA or DHA + ASA had an increase in Est, L, and CD36 expression on inflammatory monocytes and higher protein content on bronchoalveolar fluid (BALF). However, only the DHA-treated group presented a percentage of inflammatory monocytes similar to the control group and a decrease in ΔP1, L and ΔP2, L compared to Pb + DMSO. Also, combined treatment with DHA + ASA led to an impairment in diffuse alveolar damage score and lung function at 9 dpi. CONCLUSIONS: Therapy with ASA maintained lung morpho-functional impairment triggered by PbNK65 infection, leading to a large influx of inflammatory monocytes to the lung tissue. Based on its deleterious effects in experimental MA-ALI, ASA administration or its treatment maintenance might be carefully reconsidered and further investigated in human malaria cases.

Assuntos

Lesão Pulmonar Aguda , Antimaláricos , Artemisininas , Aspirina , Pulmão , Malária , Camundongos Endogâmicos C57BL , Plasmodium berghei , Animais , Artemisininas/farmacologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/parasitologia , Aspirina/farmacologia , Aspirina/administração & dosagem , Malária/tratamento farmacológico , Malária/complicações , Camundongos , Antimaláricos/farmacologia , Plasmodium berghei/efeitos dos fármacos , Pulmão/patologia , Pulmão/efeitos dos fármacos , Quimioterapia Combinada , Modelos Animais de Doenças , Masculino , Testes de Função Respiratória

RESUMO

BACKGROUND: Malaria continues to be a significant global health challenge, particularly in sub-Saharan African regions. Effective prevention and control strategies are crucial in mitigating its impact. Therefore, assessing the use of malaria preventive measures, treatment-seeking behaviours, and understanding the motivating factors behind positive behaviours/practices and barriers to using malaria preventive and control measures is essential for designing successful intervention programs. METHODS: Using a sequential explanatory mixed methods design, a descriptive cross-sectional study was conducted among 382 heads of households in the Mareba sector, Bugesera district, Rwanda. A qualitative study followed with 30 in-depth interviews among the top performers and other community members to explore the motivations and barriers to performing positive behaviours. Descriptive statistics for quantitative data and thematic analysis for qualitative data were used. RESULTS: This study revealed that among those who own insecticide-treated nets, 234(89.3%) reported that they slept under the bed net the night preceding the survey; 256(67%) had fever cases in the last 24 months preceding the survey; and 214(87%) reported seeking care within 24 h. While almost all 243(98.8%) of participants who had fever case reported that they have taken all medicines as prescribed, however, a large number 263(68.8%) and 148(38.7%) still think that there are people in the community who do not take all malaria medications as prescribed and there are people who share malaria medications in the community, respectively. 82(65.1%) of those who never had a fever case believe that they have been using malaria preventive measures correctly and consistently. This study found that knowledge about malaria, family support, and community mobilization are the top motivating factors to practice positive behaviours while, lack of bet nets, poverty, and lack of time were reported as main barriers. CONCLUSION: Interventions that target key motivating factors for adopting positive behaviours in malaria prevention and control should be prioritized. This, in turn, will reduce the disease burden on affected populations. Efforts to overcome barriers in malaria prevention and control should also be participatory. Community involvement should be at the centre of these interventions.

Assuntos

Malária , Ruanda , Malária/prevenção & controle , Estudos Transversais , Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Pessoa de Meia-Idade , Adolescente , Conhecimentos, Atitudes e Prática em Saúde , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Idoso

RESUMO

BACKGROUND: High-level resistance to sulfadoxine-pyrimethamine threatens the efficacy of WHO-recommended intermittent preventive treatment in pregnancy (IPTp) with single-dose sulfadoxine-pyrimethamine to prevent malaria. Monthly IPTp with dihydroartemisinin-piperaquine, a 3-day regimen, is an emerging alternative, but this regimen poses potential implementation and adherence challenges. We aimed to assess adherence to a multiday IPTp with dihydroartemisinin-piperaquine regimen and its delivery effectiveness in routine antenatal care settings in western Kenya. METHODS: We conducted a pragmatic, three-armed, open-label, cluster-randomised trial in antenatal clinics in 18 health-care facilities (six facilities per group) in Kisumu County and Homa Bay County in western Kenya. Clusters were facilities offering routine antenatal care services provided by trained Ministry of Health staff with 100 or more antenatal clinic attendances per month between July, 2018, and June, 2019. Private or mission hospitals, dispensaries, referral hospitals, and trial sites were excluded. Individuals in their first trimester, living with HIV, or who were not attending a scheduled antenatal clinic visit were excluded. The 18 antenatal clinics were grouped into matched triplets stratified by location and clinics in each matched triplet were randomly assigned to one of the three study groups (1:1:1). Masking was not possible. Two groups were given IPTp with dihydroartemisinin-piperaquine (one group with a targeted information transfer intervention and one group without any additional interventions) and one group was given the standard of care (ie, IPTp with sulfadoxine-pyrimethamine). The primary endpoint, adherence, was defined as the proportion of participants completing their most recent 3-day IPTp with dihydroartemisinin-piperaquine regimen. This completion was verified by pill counts during home visits no more than 2 days after participants' 3-day regimens ended. The secondary endpoint, delivery effectiveness, was defined as the proportion of participants who received the correct number of IPTp tablets and correctly repeated dosing instructions (ie, correctly recalled the instructions they received about self-administered dihydroartemisinin-piperaquine doses and the number of sulfadoxine-pyrimethamine tablets they had received) at their exit from the antenatal clinic. Individuals receiving treatment for malaria, visiting a clinic for registration only, or interviewed during IPTp drug stock-outs were excluded from analyses. We used generalised linear mixed models to compare endpoints among the IPTp with dihydroartemisinin-piperaquine groups. This trial was registered with ClinicalTrials.gov, NCT04160026, and is complete. FINDINGS: 15 facilities (five per group) completed the trial, with 1189 participants having exit interviews (377 in the IPTp with sulfadoxine-pyrimethamine group, 408 in the IPTp with dihydroartemisinin-piperaquine only group, and 404 in the IPTp with dihydroartemisinin-piperaquine plus targeted information transfer intervention group) and 586 participants having home visits (267 in the IPTp with dihydroartemisinin-piperaquine only group and 319 in the IPTp with dihydroartemisinin-piperaquine plus targeted information transfer intervention group) from Sept 8 to Dec 10, 2020. Relative to the IPTp with dihydroartemisinin-piperaquine only group, adherence was 16% higher in the IPTp with dihydroartemisinin-piperaquine plus targeted information transfer intervention group (266 [83%] of 319 participants vs 196 [73%] of 267 participants; adjusted relative risk [RR] 1·16, 95% CI 1·03-1·31; p=0·0140). Delivery effectiveness in the IPTp with dihydroartemisinin-piperaquine plus targeted information transfer intervention group was not significantly different from that in the IPTp with sulfadoxine-pyrimethamine group (352 [87%] of 403 participants vs 335 [89%] of 375 participants; adjusted RR 0·97, 95% CI 0·90-1·05; p=0·4810). However, delivery effectiveness in the IPTp with dihydroartemisinin-piperaquine only group was significantly lower than in the IPTp with sulfadoxine-pyrimethamine group (300 [74%] of 404 participants vs 335 [89%] of 375 participants; 0·84, 0·75-0·95; p=0·0030). INTERPRETATION: Targeted information transfer interventions to health-care providers and pregnant individuals boost antenatal care delivery adherence to a multiday regimen with dihydroartemisinin-piperaquine. FUNDING: European and Developing Countries Clinical Trials Partnership 2, UK Joint Global Health Trials Scheme of the Foreign, Commonwealth and Development Office, Medical Research Council, National Institute for Health and Care Research, and Wellcome Trust; and Swedish International Development Cooperation Agency.

Assuntos

Antimaláricos , Artemisininas , Combinação de Medicamentos , Malária , Complicações Parasitárias na Gravidez , Pirimetamina , Quinolinas , Sulfadoxina , Humanos , Feminino , Gravidez , Quinolinas/administração & dosagem , Quinolinas/uso terapêutico , Antimaláricos/uso terapêutico , Antimaláricos/administração & dosagem , Pirimetamina/uso terapêutico , Pirimetamina/administração & dosagem , Sulfadoxina/uso terapêutico , Sulfadoxina/administração & dosagem , Artemisininas/uso terapêutico , Artemisininas/administração & dosagem , Quênia , Adulto , Complicações Parasitárias na Gravidez/prevenção & controle , Complicações Parasitárias na Gravidez/tratamento farmacológico , Malária/prevenção & controle , Adulto Jovem , Adesão à Medicação/estatística & dados numéricos , Adolescente , Cuidado Pré-Natal/métodos , Piperazinas

RESUMO

OBJECTIVE: To perform critical methodological assessments on designs, outcomes, quality and implementation limitations of studies evaluating the impact of malaria rapid diagnostic tests (mRDTs) on patient-important outcomes in sub-Saharan Africa. DESIGN: A systematic review of study methods. DATA SOURCES: MEDLINE, EMBASE, Cochrane Library, African Index Medicus and clinical trial registries were searched up to May 2022. ELIGIBILITY CRITERIA: Primary quantitative studies that compared mRDTs to alternative diagnostic tests for malaria on patient-important outcomes within sub-Sahara Africa. DATA EXTRACTION AND SYNTHESIS: Studies were sought by an information specialist and two independent reviewers screened for eligible records and extracted data using a predesigned form using Covidence. Methodological quality was assessed using the National Institutes of Health tools. Descriptive statistics and thematic analysis guided by the Supporting the Use of Research Evidence framework were used for analysis. Findings were presented narratively, graphically and by quality ratings. RESULTS: Our search yielded 4717 studies, of which we included 24 quantitative studies; (15, 62.5%) experimental, (5, 20.8%) quasi-experimental and (4, 16.7%) observational studies. Most studies (17, 70.8%) were conducted within government-owned facilities. Of the 24 included studies, (21, 87.5%) measured the therapeutic impact of mRDTs. Prescription patterns were the most reported outcome (20, 83.3%). Only (13, 54.2%) of all studies reported statistically significant findings, in which (11, 45.8%) demonstrated mRDTs' potential to reduce over-prescription of antimalarials. Most studies (17, 70.8%) were of good methodological quality; however, reporting sample size justification needs improvement. Implementation limitations reported were mostly about health system constraints, the unacceptability of the test by the patients and low trust among health providers. CONCLUSION: Impact evaluations of mRDTs in sub-Saharan Africa are mostly randomised trials measuring mRDTs' effect on therapeutic outcomes in real-life settings. Though their methodological quality remains good, process evaluations can be incorporated to assess how contextual concerns influence their interpretation and implementation. PROSPERO REGISTRATION NUMBER: CRD42018083816.

Assuntos

Testes Diagnósticos de Rotina , Malária , Humanos , África Subsaariana , Malária/diagnóstico , Malária/tratamento farmacológico , Testes de Diagnóstico Rápido