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BACKGROUNDFeatures of consumptive coagulopathy and thromboinflammation are prominent in cerebral malaria (CM). We hypothesized that thrombogenic autoantibodies contribute to a procoagulant state in CM.METHODSPlasma from children with uncomplicated malaria (UM) (n = 124) and CM (n = 136) was analyzed by ELISA for a panel of 8 autoantibodies including anti-platelet factor 4/polyanion (anti-PF4/P), anti-phospholipid, anti-phosphatidylserine, anti-myeloperoxidase, anti-proteinase 3, anti-dsDNA, anti-ß-2-glycoprotein I, and anti-cardiolipin. Plasma samples from individuals with nonmalarial coma (NMC) (n = 49) and healthy controls (HCs) (n = 56) were assayed for comparison. Associations with clinical and immune biomarkers were determined using univariate and logistic regression analyses.RESULTSMedian anti-PF4/P and anti-PS IgG levels were elevated in individuals with malaria infection relative to levels in HCs (P < 0.001) and patients with NMC (PF4/P: P < 0.001). Anti-PF4/P IgG levels were elevated in children with CM (median = 0.27, IQR: 0.19-0.41) compared with those with UM (median = 0.19, IQR: 0.14-0.22, P < 0.0001). Anti-PS IgG levels did not differ between patients with UM and those with CM (P = 0.39). When patients with CM were stratified by malaria retinopathy (Ret) status, the levels of anti-PF4/P IgG correlated negatively with the peripheral platelet count in patients with Ret+ CM (Spearman's rho [Rs] = 0.201, P = 0.04) and associated positively with mortality (OR = 15.2, 95% CI: 1.02-275, P = 0.048). Plasma from patients with CM induced greater platelet activation in an ex vivo assay relative to plasma from patients with UM (P = 0.02), and the observed platelet activation was associated with anti-PF4/P IgG levels (Rs= 0.293, P = 0.035).CONCLUSIONSThrombosis mediated by elevated anti-PF4/P autoantibodies may be one mechanism contributing to the clinical complications of CM.
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Autoanticuerpos , Malaria Cerebral , Factor Plaquetario 4 , Humanos , Malaria Cerebral/inmunología , Malaria Cerebral/sangre , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Femenino , Masculino , Factor Plaquetario 4/inmunología , Factor Plaquetario 4/sangre , Niño , Preescolar , Lactante , Polielectrolitos , Trombosis/inmunología , Trombosis/sangreRESUMEN
BACKGROUND: Malaria remains a public health problem in regions of Northeastern India because of favourable bio-geographic transmission conditions, poor access to routine healthcare, and inadequate infrastructure for public health and disease prevention. This study was undertaken to better understand community members' and health workers' perceptions of malaria, as well as their knowledge, attitudes, and prevention practices related to the disease in Meghalaya state. METHODS: The study included participants from three malaria endemic districts: West Khasi Hills, West Jaiñtia Hills, and South Garo Hills from 2019 to 2021. A total of 82 focus group discussions (FGD) involving 694 community members and 63 in-depth interviews (IDI) with health personnel and traditional healers residing within the three districts were conducted. A thematic content analysis approach was employed, using NVivo12 software for data management. RESULTS: Most participants reported a perceived reduction in malaria during recent years, attributing this to changes in attitudes and behaviours in health seeking, and to more effective government interventions. Local availability of testing and treatment, and an improved, more responsive health system contributed to changing attitudes. Long-lasting insecticidal nets (LLINs) were largely preferred over indoor residual spraying (IRS), as LLINs were perceived to be effective and more durable. Community members also reported using personal protective measures such as applying repellents, burning neem tree leaves, straw/egg trays, wearing long sleeve clothes, and applying ointments or oils to protect themselves from mosquito bites. While most participants acknowledged the role of mosquitoes in malaria transmission, other conditions that are not mosquito-borne were also attributed to mosquitoes by some participants. The communities surveyed have largely shifted from seeking treatment for malaria from traditional healers to using public facilities, although some participants reported switching between the two or using both simultaneously. Improved understanding of cerebral malaria, which some participants previously attributed to mental illness due to 'bad spirits', is an example of how cultural and ritualistic practices have changed. CONCLUSION: The findings reveal diverse perceptions among community members regarding malaria, its prevention, practices to prevent mosquito-transmitted diseases, and their opinions about the healthcare system. A key finding was the shift in malaria treatment-seeking preferences of community members from traditional healers to the public sector. This shift highlights the changing dynamics and increasing acceptance of modern healthcare practices for malaria treatment and prevention within tribal and/or indigenous communities. By recognizing these evolving attitudes, policymakers and healthcare providers can better tailor their interventions and communication strategies to more effectively address ongoing needs and concerns as India faces the 'last mile' in malaria elimination.
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Insecticidas , Malaria Cerebral , Animales , Humanos , Personal de Salud , India/epidemiología , Conocimientos, Actitudes y Práctica en Salud , Grupos FocalesRESUMEN
Durgama Anchalare Malaria Nirakaran (DAMaN) is a multi-component malaria intervention for hard-to-reach villages in Odisha, India. The main component, malaria camps (MCs), consists of mass screening, treatment, education, and intensified vector control. We evaluated MC effectiveness using a quasi-experimental cluster-assigned stepped-wedge study with a pretest-posttest control group in 15 villages: six immediate (Arm A), six delayed (Arm B), and three previous interventions (Arm C). The primary outcome was PCR + Plasmodium infection prevalence. The time (i.e., baseline vs. follow-up 3) x study arm interaction term shows that there were statistically significant lower odds of PCR + Plasmodium infection in Arm A (AOR = 0.36, 95% CI = 0.17, 0.74) but not Arm C as compared to Arm B at the third follow-up. The cost per person ranged between US$3-8, the cost per tested US$4-9, and the cost per treated US$82-1,614, per camp round. These results suggest that the DAMaN intervention is a promising and financially feasible approach for malaria control.
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Malaria , Humanos , India/epidemiología , Malaria/epidemiología , Malaria/prevención & control , Malaria/diagnóstico , Tamizaje Masivo , PrevalenciaRESUMEN
Background: Malaria remains a public health problem in regions of northeastern India due to favourable bio-geographic transmission conditions, poor access to routine healthcare, and inadequate public health and healthcare infrastructure. This study was undertaken to better understand community members' and health workers' perceptions of malaria, as well as their knowledge, attitudes, and prevention practices related to the disease in Meghalaya state. Methods: The study included participants from three malaria endemic districts: West Khasi Hills, West Jaiñtia Hills, and South Garo Hills from 2019 to 2021. A total of 82 focus group discussions (FGD) with 694 community members and 63 in-depth interviews (IDI) with health personnel and traditional healers residing within the three districts were conducted. A thematic content analysis approach was employed, and NVivo12 software was utilized for data management. Results: Most participants reported a perceived reduction in malaria during recent years and attributed this to changing attitudes and behaviours in health seeking behaviour and effective government interventions. Local availability of testing and treatment, and an improved, more responsive health system contributed to changing attitudes. Long-lasting insecticidal nets (LLINs) were largely preferred over indoor residual spraying (IRS), as LLINs were perceived to be effective and more durable. Community members also reported using personal protective measures such as applying repellents, burning straw/egg trays, wearing long sleeve clothes, and applying ointments or oils to protect themselves from mosquito bites. While most participants acknowledged the role of mosquitoes in malaria transmission, other conditions that are not mosquito-borne were also attributed to mosquitoes by some participants. The communities surveyed have largely shifted from seeking traditional healers to using public facilities, although some participants reported switching between the two or using both simultaneously. Using the example of improved understanding of cerebral malaria which was previously attributed to mental illness due to 'bad spirits', participants explained how cultural and ritualistic practices had changed. Conclusions: Our findings reveal diverse perceptions among community members regarding malaria, its prevention, practices to prevent mosquito-transmitted diseases, and their opinions about the health system. A key finding was the shift in malaria treatment seeking preferences of community members from traditional healers to the public sector. This shift highlights the changing dynamics and increasing acceptance of modern healthcare practices for malaria treatment and prevention within tribal and/or indigenous communities. By recognizing these evolving attitudes, policymakers and healthcare providers can better tailor their interventions and communication strategies to more effectively address ongoing needs and concerns as India faces the 'last mile' in malaria elimination.
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Malaria in India is declining, in part due to the use of long-lasting insecticide-treated nets (LLINs) and vector control. Historically, the north-eastern region of India has contributed ~10%-12% of the nation's malaria burden. The important mosquito vectors in northeast India have long been considered to be Anopheles baimaii and An. minimus, both associated with forest habitats. Local deforestation and increased rice cultivation, along with widespread LLIN use, may be changing vector species composition. Understanding if and how vector species composition is changing is critical to successful malaria control. In Meghalaya state, malaria is now at a low level of endemicity with occasional seasonal outbreaks. In a biodiverse setting like Meghalaya, where >24 Anopheles mosquito species have been recorded, accurate morphological identification of all species is logistically challenging. To accurately determine Anopheles species richness in the West Khasi Hills (WKH) and West Jaintia Hills (WJH) districts, adult and larval mosquitoes were collected and identified using molecular methods of allele-specific PCR and cytochrome oxidase I DNA barcoding. In 14 villages across both districts, we identified high species richness, 19 species in total. Molecular findings indicated that An. minimus and An. baimaii were rare, while four other species (An. maculatus, An. pseudowillmori, An. jeyporiensis and An. nitidus) were abundant. Anopheles maculatus was highly prevalent in WKH (39% of light trap collections) and An. pseudowillmori in WJH (45%). Larvae of these four species were found in rice fields, suggesting that land cover change is influencing species composition change. Our results suggest that rice fields might be contributing to the observed abundance of An. maculatus and An. pseudowillmori, which could be playing a role in malaria transmission, either independently due to their high abundance, or in combination with An. baimaii and/or An. minimus.
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Anopheles , Malaria , Animales , Anopheles/genética , Malaria/epidemiología , Mosquitos Vectores/genética , India/epidemiología , Variación GenéticaRESUMEN
Malaria remains a global concern despite substantial reduction in incidence over the past twenty years. Public health interventions to increase the uptake of preventive measures have contributed to this decline but their impact has not been uniform. To date, we know little about what determines the use of preventive measures in rural, hard-to-reach populations, which are crucial contexts for malaria eradication. We collected detailed interview data on the use of malaria preventive measures, health-related discussion networks, individual characteristics, and household composition in ten tribal, malaria-endemic villages in Meghalaya, India in 2020-2021 (n=1,530). Employing standard and network statistical models, we found that social network and household exposure were consistently positively associated with preventive measure use across villages. Network and household exposure were also the most important factors explaining behaviour, outweighing individual characteristics, opinion leaders, and network size. These results suggest that real-life data on social networks and household composition should be considered in studies of health-behaviour change.
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Durgama Anchalare Malaria Nirakaran (DAMaN) is a multi-component malaria intervention for hard-to-reach villages in Odisha, India. The main component, Malaria Camps (MCs), consists of mass screening, treatment, education, and intensified vector control. We evaluated MC effectiveness using a quasi-experimental cluster-assigned stepped-wedge study with a pretest-posttest control group in 15 villages: six immediate (Arm A), six delayed (Arm B), and three previous interventions (Arm C). The primary outcome was PCR+ Plasmodium infection prevalence. Across all arms, the odds of PCR+ malaria were 54% lower at the third follow-up compared to baseline. A time (i.e., visit) x study arm interaction revealed significantly lower odds of PCR+ malaria in Arm A versus B at the third follow-up. The cost per person ranged between US$3-8, the cost per tested US$4-7, and the cost per treated US$82-1,614, per camp round. These results suggest that the DAMaN intervention is a promising, financially feasible approach for malaria control.
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The Center for the Study of Complex Malaria in India (CSCMi) is one of 10 International Centers of Excellence in Malaria Research funded by the National Institutes of Health since 2010. The Center combines innovative research with capacity building and technology transfer to undertake studies with clinical and translational impact that will move malaria control in India toward the ultimate goal of malaria elimination/eradication. A key element of each research site in the four states of India (Tamil Nadu, Gujarat, Odisha, and Meghalaya) has been undertaking community- and clinic-based epidemiology projects to characterize the burden of malaria in the region. Demographic and clinical data and samples collected during these studies have been used in downstream projects on, for example, the widespread use of mosquito repellants, the population genomics of Plasmodium vivax, and the serological responses to P. vivax and Plasmodium falciparum antigens that reflect past or present exposure. A focus has been studying the pathogenesis of severe malaria caused by P. falciparum through magnetic resonance imaging of cerebral malaria patients. Here we provide a snapshot of some of the basic and applied research the CSCMi has undertaken over the past 12 years and indicate the further research and/or clinical and translational impact these studies have had.
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Malaria Falciparum , Malaria Vivax , Malaria , Animales , Humanos , India/epidemiología , Malaria/epidemiología , Malaria/prevención & control , Malaria Falciparum/epidemiología , Malaria Falciparum/prevención & control , Malaria Vivax/epidemiología , Plasmodium falciparum/genética , Plasmodium vivax/genética , Investigación Biomédica TraslacionalRESUMEN
The Center for the Study of Complex Malaria in India (CSCMi) was launched in 2010 with the overall goal of addressing major gaps in our understanding of "complex malaria" in India through projects on the epidemiology, transmission, and pathogenesis of the disease. The Center was mandated to adopt an integrated approach to malaria research, including building capacity, developing infrastructure, and nurturing future malaria leaders while conducting relevant and impactful studies to assist India as it moves from control to elimination. Here, we will outline some of the interactions and impacts the Center has had with malaria policy and control counterparts in India, as well as describe emerging needs and new research questions that have become apparent over the past 12 years.
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Malaria , Humanos , India/epidemiología , Malaria/epidemiología , Malaria/prevención & controlRESUMEN
BACKGROUND: A detailed analysis of household and individual level Plasmodium infection patterns in two low-endemic districts of Meghalaya was undertaken to better understand the epidemiology of malaria in northeast India. METHODS: Socio-demographic and behavioural information from residents (aged 1-69 years) of households were collected through pre-tested, questionnaire conducted in 2018 and 2019. Blood samples collected from participants were tested for Plasmodium falciparum and/or Plasmodium vivax infection using rapid diagnostic test, microscopy and PCR. Plasma samples from a subset of participants were analysed for antibodies against thirteen P. falciparum and four P. vivax antigens. Associations between household and individual level risk factors, and Plasmodium infections were evaluated using multilevel logistic regression models. RESULTS: A total of 2753 individuals from 827 households were enrolled in 2018, and 834 individuals from 222 households were enrolled in 2019. Of them, 33 (1.2%) were positive by PCR for P. falciparum in 2018 and none were positive for P. vivax. In 2019, no PCR-positive individuals were detected. All, but one, infections were asymptomatic; all 33 infections were sub-microscopic. Reported history of malaria in the past 12 months (OR = 8.84) and history of travel in the past 14 days (OR = 10.06) were significantly associated with Plasmodium infection. A significant trend of increased seropositivity with age was noted for all 17 antigens. Although adults (≥ 18 years) consistently had the highest seropositivity rates, a sizeable proportion of under-five children were also found to be seropositive. Almost all individuals (99.4%) reported sleeping under an insecticide-treated bed-net, and household indoor residual spray coverage in the 12 months preceding the survey was low (23%). Most participants correctly identified common signs and symptoms of malaria, i.e., fever (96.4%), headache (71.2%), chills (83.2%) and body-ache (61.8%). Almost all participants (94.3%) used government-provided services for treatment of malaria. CONCLUSION: This study explored the epidemiology of malaria in two communities in Meghalaya, India, in the context of declining transmission. The presence of widespread asymptomatic infections and seropositivity among under-five children suggest that low-level Plasmodium transmission persists in this region. Implications of the study findings for malaria elimination efforts in low-transmission settings are discussed.
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Malaria Falciparum/epidemiología , Malaria Vivax/epidemiología , Infecciones Asintomáticas/epidemiología , Estudios Transversales , Composición Familiar , Femenino , Humanos , Incidencia , India/epidemiología , Malaria Falciparum/prevención & control , Malaria Vivax/prevención & control , Masculino , Plasmodium falciparum/aislamiento & purificación , Plasmodium vivax/aislamiento & purificación , Factores de RiesgoRESUMEN
The Indian state of Odisha has a longstanding battle with forest malaria. Many remote and rural villages have poor access to health care, a problem that is exacerbated during the rainy season when malaria transmission is at its peak. Approximately 62% of the rural population consists of tribal groups who are among the communities most negatively impacted by malaria. To address the persistently high rates of malaria in these remote regions, the Odisha State Malaria Control Program introduced 'malaria camps' in 2017 where teams of health workers visit villages to educate the population, enhance vector control methods, and perform village-wide screening and treatment. Malaria rates declined statewide, particularly in forested areas, following the introduction of the malaria camps, but the impact of the intervention is yet to be externally evaluated. This study protocol describes a cluster-assigned quasi-experimental stepped-wedge study with a pretest-posttest control group design that evaluates if malaria camps reduce the prevalence of malaria, compared to control villages which receive the usual malaria control interventions (e.g. IRS, ITNs), as detected by PCR.
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Malaria , Humanos , India/epidemiología , Malaria/tratamiento farmacológico , Malaria/epidemiología , Malaria/prevención & control , Reacción en Cadena de la Polimerasa , Prevalencia , Población RuralRESUMEN
BACKGROUND: Despite declining incidence over the past decade, malaria remains an important health burden in India. This study aimed to assess the village-level temporal patterns of Plasmodium infection in two districts of the north-eastern state of Meghalaya and evaluate risk factors that might explain these patterns. METHODS: Primary Health Centre passive malaria case data from 2014 to 2018 were analysed to characterize village-specific annual incidence and temporal trends. Active malaria case detection was undertaken in 2018 and 2019 to detect Plasmodium infections using PCR. A questionnaire collected socio-demographic, environmental, and behavioural data, and households were spatially mapped via GPS. Adult mosquitoes were sampled at a subset of subjects' houses, and Anopheles were identified by PCR and sequencing. Risk factors for Plasmodium infection were evaluated using bivariate and multivariate logistic regression analysis, and spatial cluster analysis was undertaken. RESULTS: The annual malaria incidence from PHC-based passive surveillance datasets in 2014-2018 was heterogenous but declining across villages in both districts. Active surveillance in 2018 enrolled 1468 individuals from 468 households (West Jaintia Hills) and 1274 individuals from 359 households (West Khasi Hills). Plasmodium falciparum prevalence per 100 people varied from 0 to 4.1% in the nine villages of West Jaintia Hills, and from 0 to 10.6% in the 12 villages of West Khasi Hills. Significant clustering of P. falciparum infections [observed = 11, expected = 2.15, Relative Risk (RR) = 12.65; p < 0.001] was observed in West Khasi Hills. A total of 13 Anopheles species were found at 53 houses in five villages, with Anopheles jeyporiensis being the most abundant. Risk of infection increased with presence of mosquitoes and electricity in the households [Odds Ratio (OR) = 1.19 and 1.11], respectively. Households with reported animals had reduced infection risk (OR = 0.91). CONCLUSION: Malaria incidence during 2014-2018 declined in all study villages covered by the passive surveillance data, a period that includes the first widespread insecticide-treated net campaign. The survey data from 2018 revealed a significant association between Plasmodium infection and certain household characteristics. Since species of Plasmodium-competent mosquito vectors continue to be abundant, malaria resurgence remains a threat, and control efforts should continue.
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Anopheles/parasitología , Malaria Falciparum/epidemiología , Mosquitos Vectores/parasitología , Plasmodium falciparum/aislamiento & purificación , Adolescente , Adulto , Anciano , Animales , Niño , Preescolar , Femenino , Humanos , India/epidemiología , Lactante , Malaria Falciparum/parasitología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Adulto JovenRESUMEN
Our institute of Legal Medicine was asked to examine a 27-year-old patient admitted to the neurosurgical department after a non-fatal accident (non-observed fall from height) at a construction site. Forensic advice was needed because of unexplainable injuries. By example of this case of a near-to-impalement, we would like to highlight an unusual, clinically frequently forgotten, and forensically thus far not discussed type of skull fracture with outward dislocation of bone fragment(s). These so-called compound elevated fractures of the skull are described occasionally in, mainly neurosurgical, case reports. Knowing its entity and its pathomechanism may be of forensic interest, particularly in order of reconstruction purpose. This article provides a brief review of the literature with special regard to the pathomechanism. In addition, it demonstrates the possible pitfall of computed tomography, or more specifically, the 3D reconstruction. To our knowledge, this is the first forensic report describing this kind of fracture.
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Medicina Legal , Fracturas Abiertas/etiología , Fracturas Craneales/etiología , Accidentes por Caídas , Adulto , Fracturas Abiertas/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Masculino , Fracturas Craneales/diagnóstico por imagen , Tomografía Computarizada por Rayos XAsunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Neumonía Lipoidea/inducido químicamente , Diagnóstico Diferencial , Femenino , Glucocorticoides/uso terapéutico , Humanos , Persona de Mediana Edad , Neumonía Lipoidea/diagnóstico por imagen , Neumonía Lipoidea/tratamiento farmacológico , Prednisolona/uso terapéutico , Suiza , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUNDPrediction of adverse outcomes in cerebral malaria (CM) is difficult. We hypothesized that cell-free DNA (cfDNA) levels would facilitate identification of severe and potentially fatal CM cases.METHODSIn this retrospective study, plasma from Malawian children with CM (n = 134), uncomplicated malaria (UM, n = 77), and healthy controls (HC, n = 60) was assayed for cfDNA using a fluorescence assay. Host and parasite cfDNA was measured by quantitative PCR. Immune markers were determined by ELISA, Luminex, or cytometric bead array.RESULTSTotal cfDNA increased with malaria severity (HC versus UM, P < 0.001; HC versus CM, P < 0.0001; UM versus CM, P < 0.0001), was elevated in retinopathy-positive (Ret+) CM relative to Ret- CM (7.66 versus 5.47 ng/µL, P = 0.027), and differentiated Ret+ fatal cases from survivors (AUC 0.779; P < 0.001). cfDNA levels in patients with non-malarial febrile illness (NMF, P = 0.25) and non-malarial coma (NMC, P = 0.99) were comparable with UM. Host DNA, rather than parasite DNA, was the major cfDNA contributor (UM, 268 versus 67 pg/µL; CM, 2824 versus 463 pg/µL). Host and parasite cfDNA distinguished CM by retinopathy (host, AUC 0.715, P = 0.0001; parasite, AUC 0.745, P = 0.0001), but only host cfDNA distinguished fatal cases (AUC 0.715, P = 0.0001). Total cfDNA correlated with neutrophil markers IL-8 (rs = 0.433, P < 0.0001) and myeloperoxidase (rs = 0.683, P < 0.0001).CONCLUSIONQuantifying plasma cfDNA is a simple assay useful in identifying children at risk for fatal outcome and has promise as a point-of-care assay. Elevated cfDNA suggests a link with host inflammatory pathways in fatal CM.FUNDINGNIH NCATS (AK), Burroughs-Wellcome (AK), and National Health and Medical Research Council of Australia (SJR).
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Biomarcadores/sangre , Ácidos Nucleicos Libres de Células/sangre , Malaria Cerebral/diagnóstico , Malaria Falciparum/sangre , Plasma/metabolismo , Adolescente , Niño , Preescolar , Femenino , Humanos , Malaria Cerebral/sangre , Malaria Cerebral/parasitología , Malaria Falciparum/diagnóstico , Masculino , Neutrófilos/metabolismoRESUMEN
The clinical presentation of severe Plasmodium falciparum malaria differs between children and adults, but the mechanistic basis for this remains unclear. Contributing factors to disease severity include total parasite biomass and the diverse cytoadhesive properties mediated by the polymorphic var gene parasite ligand family displayed on infected erythrocytes. To explore these factors, we performed a multicohort analysis of the contribution of var expression and parasite biomass to severe malaria in two previously published pediatric cohorts in Tanzania and Malawi and an adult cohort in India. Machine learning analysis revealed independent and complementary roles for var adhesion types and parasite biomass in adult and pediatric severe malaria and showed that similar var profiles, including upregulation of group A and DC8 var, predict severe malaria in adults and children. Among adults, patients with multiorgan complications presented infections with significantly higher parasite biomass without significant differences in var adhesion types. Conversely, pediatric patients with specific complications showed distinct var signatures. Cerebral malaria patients showed broadly increased expression of var genes, in particular group A and DC8 var, while children with severe malaria anemia were classified based on high transcription of DC8 var only. This study represents the first large multisite meta-analysis of var expression, and it demonstrates the presence of common var profiles in severe malaria patients of different ages across distant geographical sites, as well as syndrome-specific disease signatures. The complex associations between parasite biomass, var adhesion type, and clinical presentation revealed here represent the most comprehensive picture so far of the relationship between cytoadhesion, parasite load, and clinical syndrome.IMPORTANCEP. falciparum malaria can cause multiple disease complications that differ by patient age. Previous studies have attempted to address the roles of parasite adhesion and biomass in disease severity; however, these studies have been limited to single geographical sites, and there is limited understanding of how parasite adhesion and biomass interact to influence disease manifestations. In this meta-analysis, we compared parasite disease determinants in African children and Indian adults. This study demonstrates that parasite biomass and specific subsets of var genes are independently associated with detrimental outcomes in both childhood and adult malaria. We also explored how parasite var adhesion types and biomass play different roles in the development of specific severe malaria pathologies, including childhood cerebral malaria and multiorgan complications in adults. This work represents the largest study to date of the role of both var adhesion types and biomass in severe malaria.
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Variación Genética , Genotipo , Malaria Falciparum/patología , Malaria Falciparum/parasitología , Plasmodium falciparum/clasificación , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Adulto , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , India , Lactante , Aprendizaje Automático , Malaui , Masculino , Carga de Parásitos , TanzaníaRESUMEN
BACKGROUND: Cerebral malaria (CM) is often fatal, and severe brain swelling is a predictor of CM-related mortality. CM is characterized by elevated circulating pro-inflammatory cytokines TNF and IFN-γ and anti-inflammatory cytokine IL-10, however whether cytokine levels correlate with brain swelling severity is unknown. This study therefore was conducted to investigate the relationship between cytokine levels and brain swelling severity in children presenting with CM. METHODS: A total of 195 Malawian children presenting with CM were recruited and had the concentrations of plasma cytokines determined and compared to brain swelling severity, determined by MRI examination, and graded as severe, moderate, mild or none. RESULTS: Levels of IL-1ß, IL-6, IL-8 and IL-10 did not differ between CM patients with and without severe brain swelling. Compared to children without brain swelling, IL-12 levels were higher in children with severe swelling (p < 0.01, no swelling 1 pg/mL, IQR [1] vs. severe swelling 18.7 pg/mL, IQR [1-27]), whereas TNF concentrations were higher in children with moderate brain swelling compared to children with no swelling (p < 0.01, no swelling 3 pg/mL, IQR [1-20] vs. moderate swelling 24 pg/mL, IQR [8-58]. Multivariate analysis showed that no single cytokine independently predicted brain swelling. CONCLUSION: Severe brain swelling in paediatric CM was independent of tested blood pro-inflammatory and anti-inflammatory cytokines which are markers of systemic inflammation.
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Edema Encefálico/patología , Citocinas/sangre , Malaria Cerebral/patología , Plasma/química , Edema Encefálico/diagnóstico por imagen , Niño , Preescolar , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Malaui , Masculino , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: Meghalaya, one of eight states in the northeastern region of India, has been reported to carry a high malaria burden. However, malaria surveillance, epidemiology, and vector studies are sparse, and no reviews combining these topics with malaria prevention and control strategies have been published in recent years. Furthermore, no analysis of surveillance data has been published documenting the changes in epidemiology following the first distribution of long-lasting insecticidal nets (LLINs) statewide in 2016. METHODS: A hybrid approach was used to describe the status of malaria in Meghalaya. First, a literature search was performed using the terms 'malaria' and 'Meghalaya'. Second, data were obtained from the Meghalaya State Malaria Control Programme for 2006-2017 for analysis of trends. Data from 3 years 2015-2017 were analysed further by district and year to assess changes in malaria incidence and distribution following the introduction of LLINs. RESULTS/CONCLUSIONS: Like malaria in mainland India, malaria in Meghalaya is complex, with both Plasmodium falciparum and Plasmodium vivax parasites in circulation, multiple Anopheles vector species, and reports of both unusual and severe malaria syndromes across all age groups. Integrated statewide malaria epidemiology, vector, and prevention and control data for Meghalaya are not readily available, and published studies are largely focused on a single topic or a single district or region of the state. Although malaria prevention and control approaches are available, (e.g. spraying, LLINs, personal repellents), their use and effectiveness is also not well characterized in the literature. Analysis of state malaria control programme data indicates that case incidence and related fatalities in Meghalaya have declined over the last decade. This could be attributed to changes in treatment guidelines and/or statewide distribution of effective prevention methods such as LLINs. Since the distribution of more than 900,000 LLINs in 2016, the malaria caseload has declined significantly in most Meghalaya districts, excluding the remote and geographically isolated South Garo Hills. Additionally, the proportion of adult malaria cases (15+ years of age versus children 0-14 years) in most districts was significantly greater following LLIN distribution, which likely reflects common lifestyle practices in these areas (e.g. adults working during night hours; small children in the households receiving priority for bed net protection). While reduction in malaria case incidence and related deaths is clear, the changes in malaria transmission and clinical manifestation have not been characterized. Routine epidemiology and vector surveillance combined with real-time data reporting are essential for the continued reduction and eventual elimination of malaria in Meghalaya.
Asunto(s)
Anopheles/fisiología , Malaria Falciparum , Malaria Vivax , Plasmodium falciparum/fisiología , Plasmodium vivax/fisiología , Animales , Humanos , Incidencia , India/epidemiología , Malaria Falciparum/epidemiología , Malaria Falciparum/prevención & control , Malaria Falciparum/transmisión , Malaria Vivax/epidemiología , Malaria Vivax/prevención & control , Malaria Vivax/transmisión , Mosquitos Vectores/fisiología , PrevalenciaRESUMEN
BACKGROUND: Antibody immunity is thought to be essential to prevent severe Plasmodium falciparum infection, but the exact correlates of protection are unknown. Over time, children in endemic areas acquire non-sterile immunity to malaria that correlates with development of antibodies to merozoite invasion proteins and parasite proteins expressed on the surface of infected erythrocytes. RESULTS: A 1000 feature P. falciparum 3D7 protein microarray was used to compare P. falciparum-specific seroreactivity during acute infection and 30 days after infection in 23 children with uncomplicated malaria (UM) and 25 children with retinopathy-positive cerebral malaria (CM). All children had broad P. falciparum antibody reactivity during acute disease. IgM reactivity decreased and IgG reactivity increased in convalescence. Antibody reactivity to CIDR domains of "virulent" PfEMP1 proteins was low with robust reactivity to the highly conserved, intracellular ATS domain of PfEMP1 in both groups. Although children with UM and CM differed markedly in parasite burden and PfEMP1 exposure during acute disease, neither acute nor convalescent PfEMP1 seroreactivity differed between groups. Greater seroprevalence to a conserved Group A-associated ICAM binding extracellular domain was observed relative to linked extracellular CIDRα1 domains in both case groups. Pooled immune IgG from Malawian adults revealed greater reactivity to PfEMP1 than observed in children. CONCLUSIONS: Children with uncomplicated and cerebral malaria have similar breadth and magnitude of P. falciparum antibody reactivity. The utility of protein microarrays to measure serological recognition of polymorphic PfEMP1 antigens needs to be studied further, but the study findings support the hypothesis that conserved domains of PfEMP1 are more prominent targets of cross reactive antibodies than variable domains in children with symptomatic malaria. Protein microarrays represent an additional tool to identify cross-reactive Plasmodium antigens including PfEMP1 domains that can be investigated as strain-transcendent vaccine candidates.
Asunto(s)
Inmunidad Adaptativa/inmunología , Antígenos de Protozoos/inmunología , Malaria Falciparum/inmunología , Adolescente , Niño , Preescolar , Convalecencia , Femenino , Humanos , Lactante , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaui/epidemiología , Masculino , Plasmodium falciparum/inmunología , Prevalencia , Estudios SeroepidemiológicosRESUMEN
Brain swelling is a major predictor of mortality in pediatric cerebral malaria (CM). However, the mechanisms leading to swelling remain poorly defined. Here, we combined neuroimaging, parasite transcript profiling, and laboratory blood profiles to develop machine-learning models of malarial retinopathy and brain swelling. We found that parasite var transcripts encoding endothelial protein C receptor (EPCR)-binding domains, in combination with high parasite biomass and low platelet levels, are strong indicators of CM cases with malarial retinopathy. Swelling cases presented low platelet levels and increased transcript abundance of parasite PfEMP1 DC8 and group A EPCR-binding domains. Remarkably, the dominant transcript in 50% of swelling cases encoded PfEMP1 group A CIDRα1.7 domains. Furthermore, a recombinant CIDRα1.7 domain from a pediatric CM brain autopsy inhibited the barrier-protective properties of EPCR in human brain endothelial cells in vitro. Together, these findings suggest a detrimental role for EPCR-binding CIDRα1 domains in brain swelling.