Temporal and spatial dynamics of Plasmodium falciparum clonal lineages in Guyana.

Plasmodium parasites, the causal agents of malaria, are eukaryotic organisms that obligately undergo sexual recombination within mosquitoes. In low transmission settings, parasites recombine with themselves, and the clonal lineage is propagated rather than broken up by outcrossing. We investigated whether stochastic/neutral factors drive the persistence and abundance of Plasmodium falciparum clonal lineages in Guyana, a country with relatively low malaria transmission, but the only setting in the Americas in which an important artemisinin resistance mutation (pfk13 C580Y) has been observed. We performed whole genome sequencing on 1,727 Plasmodium falciparum samples collected from infected patients across a five-year period (2016-2021). We characterized the relatedness between each pair of monoclonal infections (n = 1,409) through estimation of identity-by-descent (IBD) and also typed each sample for known or candidate drug resistance mutations. A total of 160 multi-isolate clones (mean IBD ≥ 0.90) were circulating in Guyana during the study period, comprising 13 highly related clusters (mean IBD ≥ 0.40). In the five-year study period, we observed a decrease in frequency of a mutation associated with artemisinin partner drug (piperaquine) resistance (pfcrt C350R) and limited co-occurence of pfcrt C350R with duplications of plasmepsin 2/3, an epistatic interaction associated with piperaquine resistance. We additionally observed 61 nonsynonymous substitutions that increased markedly in frequency over the study period as well as a novel pfk13 mutation (G718S). However, P. falciparum clonal dynamics in Guyana appear to be largely driven by stochastic factors, in contrast to other geographic regions, given that clones carrying drug resistance polymorphisms do not demonstrate enhanced persistence or higher abundance than clones carrying polymorphisms of comparable frequency that are unrelated to resistance. The use of multiple artemisinin combination therapies in Guyana may have contributed to the disappearance of the pfk13 C580Y mutation.

The establishment of a collaborative surveillance program with indigenous hunters to characterize primate health in Southern Guyana.

The consumption of primates is integral to the traditional subsistence strategies of many Indigenous communities throughout Amazonia. Understanding the overall health of primates harvested for food in the region is critical to Indigenous food security and thus, these communities are highly invested in long-term primate population health. Here, we describe the establishment of a surveillance comanagement program among the Waiwai, an Indigenous community in the Konashen Amerindian Protected Area (KAPA). To assess primate health in the KAPA, hunters performed field necropsies on primates harvested for food and tissues collected from these individuals were analyzed using histopathology. From 2015 to 2019, hunters conducted 127 necropsies across seven species of primates. Of this sample, 82 primates (between 2015 and 2017) were submitted for histopathological screening. Our histopathology data revealed that KAPA primates had little evidence of underlying disease. Of the tissue abnormalities observed, the majority were either due to diet (e.g., hepatocellular pigment), degenerative changes resulting from aging (e.g., interstitial nephritis, myocyte lipofusion), or nonspecific responses to antigenic stimulation (renal and splenic lymphoid hyperplasia). In our sample, 7.32% of individuals had abnormalities that were consistent with a viral etiology, including myocarditis and hepatitis. Internal parasites were observed in 53.66% of individuals and is consistent with what would be expected from a free-ranging primate population. This study represents the importance of baseline data for long-term monitoring of primate populations hunted for food. More broadly, this research begins to close a critical gap in zoonotic disease risk related to primate harvesting in Amazonia, while also demonstrating the benefits of partnering with Indigenous hunters and leveraging hunting practices in disease surveillance and primate population health assessment.

A new cryptic species of Imparfinis (Siluriformes: Heptapteridae) from the Orinoco River basin, revealed by an iterative approach.

An iterative analysis of Imparfinis, combining phylogenetic analysis based on cytochrome oxidase gene and multivariate morphometrics, revealed a new cryptic species from the Andean tributaries of the Orinoco River basin, which is described here. The new species is sister to a clade constituted by Imparfinis hasemani and Imparfinis pijpersi, both from the river basins of the Guiana Shield, being also the most geographically proximate species. Nonetheless, the new species is most similar in general appearance to Imparfinis guttatus from the Madeira and Paraguay River drainages, being almost undistinguishable by conventional characters of external morphology, differing only by morphometric attributes overall. The new species can be distinguished from the remaining congeners by a unique combination of characters, including lower lobe of caudal fin darker than upper lobe, maxillary barbel reaching or surpassing pelvic-fin insertion, 12-15 gill rakers on first gill arch, 40-42 total vertebrae and 9-10 ribs. The new species constitutes the only representative from the Orinoco River basin belonging to Imparfinis sensu stricto.

Socioeconomic and home educational resource risk factors and Children's literacy and social skills in Guyanese families: Mediating role of parental cognitive engagement and parental guidance.

This study examined the mediating role of parental cognitive engagement and parental guidance on the associations between family socioeconomic and home environment resource risk factors and children's literacy and social skills in Guyana. The sample consisted of 1208 families from diverse ethnic and socioeconomic backgrounds drawn from the 2019 to 2020 country-level UNICEF MICS data. Caregivers provided assessments of socioeconomic conditions, educational resources in the home environment, cognitive engagement, parental guidance and children's literacy and social skills. Family socioeconomic risk had an indirect association with social skills through cognitive engagement. Home environment educational resource risk had indirect associations with children's literacy and social skills through parental guidance. Findings are discussed in terms of identifying protective factors within families in low- and middle-income Caribbean countries that can better inform intervention efforts geared at reducing risks to childhood development.

A nowcasting framework for correcting for reporting delays in malaria surveillance.

Time lags in reporting to national surveillance systems represent a major barrier for the control of infectious diseases, preventing timely decision making and resource allocation. This issue is particularly acute for infectious diseases like malaria, which often impact rural and remote communities the hardest. In Guyana, a country located in South America, poor connectivity among remote malaria-endemic regions hampers surveillance efforts, making reporting delays a key challenge for elimination. Here, we analyze 13 years of malaria surveillance data, identifying key correlates of time lags between clinical cases occurring and being added to the central data system. We develop nowcasting methods that use historical patterns of reporting delays to estimate occurred-but-not-reported monthly malaria cases. To assess their performance, we implemented them retrospectively, using only information that would have been available at the time of estimation, and found that they substantially enhanced the estimates of malaria cases. Specifically, we found that the best performing models achieved up to two-fold improvements in accuracy (or error reduction) over known cases in selected regions. Our approach provides a simple, generalizable tool to improve malaria surveillance in endemic countries and is currently being implemented to help guide existing resource allocation and elimination efforts.

Malaria care-seeking and treatment ideation among gold miners in Guyana.

BACKGROUND: Although miners are a priority population in malaria elimination in Guyana, scant literature exists on the drivers of malaria-related behaviour. This study explores the relationship between gold miners' malaria-related ideation and the adoption of malaria care-seeking and treatment behaviours including prompt care-seeking, malaria testing, and self-medication. METHODS: Data are from a cross-sectional quantitative survey of 1685 adult miners between the ages of 18-59 years who live in mining camps in Regions 1, 7, and 8. The analysis focused on miners who reported an episode of fever in the past year (n = 745). Malaria care-seeking and treatment ideation was defined as a composite additive score consisting of the following variables: general malaria knowledge, perceived severity, perceived susceptibility, beliefs, perceived self-efficacy, perceived norms, interpersonal communication, and perceived response efficacy. Multivariable logistic regressions explored the relationship between ideation on care-seeking/treatment behaviours, controlling for confounding variables. RESULTS: Most miners with a recent episode of fever had perceived risk (92%), self-efficacy (67%), susceptibility (53%) and high malaria knowledge (53%). Overall, miners' care-seeking/treatment ideation score ranged from 0 to 8 with a mean of 4.1. Ideation scores were associated with higher odds of care-seeking for fever (aOR: 1.19; 95% CI 1.04-1.36), getting tested for malaria (aOR: 1.22; 95% CI 1.07-1.38) and lower odds of self-medication (aOR: 0.87; 95% CI 0.77-0.99). CONCLUSIONS: A national community case management initiative is using study findings as part of its scale-up, using volunteers to make testing and treatment services more accessible to miners. This is complemented by a multi-channel mass media campaign to improve miners' ideation. Communication messages focus on increasing miners' knowledge of malaria transmission and symptoms, encourage positive beliefs about malaria testing and volunteer testers, promote evidence about the effectiveness of testing, and reminders of how quick and easy it is to get a malaria test with the community case management initiative. Study findings also have implications for efforts to eliminate malaria across the Guiana Shield.

Evidence that a national REDD+ program reduces tree cover loss and carbon emissions in a high forest cover, low deforestation country.

Reducing emissions from deforestation and forest degradation (REDD+) is a climate change mitigation policy in which rich countries provide payments to developing countries for protecting their forests. In 2009, the countries of Norway and Guyana entered into one of the first bilateral REDD+ programs, with Norway offering to pay US$250 million to Guyana if annual deforestation rates remained below 0.056% from 2010 to 2015. To quantify the impact of this national REDD+ program, we construct a counterfactual times-series trajectory of annual tree cover loss using synthetic matching. This analytical approach allows us to quantify tree cover loss that would have occurred in the absence of the Norway-Guyana REDD+ program. We found that the Norway-Guyana REDD+ program reduced tree cover loss by 35% during the implementation period (2010 to 2015), equivalent to 12.8 million tons of avoided CO2 emissions. Our analysis indicates that national REDD+ payments attenuated the effect of increases in gold prices, an internationally traded commodity that is the primary deforestation driver in Guyana. Overall, we found strong evidence that the program met the additionality criteria of REDD+. However, we found that tree cover loss increased after the payments ended, and therefore, our results suggest that without continued payments, forest protection is not guaranteed. On the issue of leakage, which is complex and difficult to quantify, a multinational REDD+ program for a region could address leakage that results from differences in forest policies between neighboring countries.

Positive Effect of Ecological Restoration with Fabaceous Species on Microbial Activities of Former Guyanese Mining Sites.

Understanding ecological trajectories after mine site rehabilitation is essential to develop relevant protocols adapted for gold mining sites. This study describes the influence of a range of mine site rehabilitation and revegetation protocols on soil physicochemical parameters and microbial activities related to carbon, nitrogen and phosphorus cycles. We sampled soil from six rehabilitated mining sites in French Guiana with different plant cover (herbaceous, Cyperaceous, monoculture of Clitoria racemosa and Acacia mangium and association of C. racemosa and A. mangium). We measured the mineralization potential of organic matter by estimating the mineralization of carbon, nitrogen and phosphorus and the microbial catabolic diversity balance. The results showed an improvement in the quality of organic matter on revegetated sites with tree cover. On restored sites with fabaceous species, the microbial biomass is three times higher than non-restored sites, improving the rates of organic matter mineralization and restoring the catabolic diversity to the level of natural Guyanese soils. These results confirm that the establishment of fabaceous species under controlled conditions significantly improves the restoration of microbial communities in mining soils.

Cross-border malaria in Northern Brazil.

BACKGROUND: Cross-border malaria is a major barrier to elimination efforts. Along the Venezuela-Brazil-Guyana border, intense human mobility fueled primarily by a humanitarian crisis and illegal gold mining activities has increased the occurrence of cross-border cases in Brazil. Roraima, a Brazilian state situated between Venezuela and Guyana, bears the greatest burden. This study analyses the current cross-border malaria epidemiology in Northern Brazil between the years 2007 and 2018. METHODS: De-identified data on reported malaria cases in Brazil were obtained from the Malaria Epidemiological Surveillance Information System for the years 2007 to 2018. Pearson's Chi-Square test of differences was utilized to assess differences between characteristics of cross-border cases originating from Venezuela and Guyana, and between border and transnational cases. A logistic regression model was used to predict imported status of cases. RESULTS: Cross-border cases from Venezuela and Guyana made up the majority of border and transnational cases since 2012, and Roraima remained the largest receiving state for cross-border cases over this period. There were significant differences in the profiles of border and transnational cases originating from Venezuela and Guyana, including type of movement and nationality of patients. Logistic regression results demonstrated Venezuelan and Guyanese nationals, Brazilian miners, males, and individuals of working age had heightened odds of being an imported case. Furthermore, Venezuelan citizens had heightened odds of seeking care in municipalities adjacent Venezuela, rather than transnational municipalities. CONCLUSIONS: Cross-border malaria contributes to the malaria burden at the Venezuela-Guyana-Brazil border. The identification of distinct profiles of case importation provides evidence on the need to strengthen surveillance at border areas, and to deploy tailored strategies that recognize different mobility routes, such as the movement of refuge-seeking individuals and of Brazilians working in mining.

Understanding the distribution of bushmeat hunting effort across landscapes by testing hypotheses about human foraging.

Mitigating the massive impacts of defaunation on natural ecosystems requires understanding and predicting hunting effort across the landscape. But such understanding has been hindered by the difficulty of assessing the movement patterns of hunters in thick forests and across complex terrain. We statistically tested hypotheses about the spatial distribution of hunting with circuit theory and structural equation models. We used a data set of >7000 known kill locations in Guyana and hunter movement models to test these methods. Comparing models with different resistance layers (i.e., different estimates of how terrain and land cover influence human movement speed) showed that rivers, on average, limited movement rather than serving as transport arteries. Moreover, far more kills occurred close to villages than in remote areas. This, combined with the lack of support for structural equation models that included latent terms for prey depletion driven by past overhunting, suggests that kill locations in this system tended to be driven by where hunters were currently foraging rather than by influences of historical harvest. These analyses are generalizable to a variety of ecosystems, species, and data types, providing a powerful way of enhancing maps and predictions of hunting effort across complex landscapes.

Comprensión de la Distribución de los Esfuerzos por Obtener Carne de Caza a lo largo de un Paisaje Mediante la Comprobación de Hipótesis sobre el Forrajeo Humano Resumen La mitigación de los impactos masivos de la defaunación sobre los ecosistemas naturales requiere de comprensión y predicción de los esfuerzos de caza a lo largo del paisaje. Dicha comprensión se ha visto obstaculizada por la dificultad que representa la evaluación de los patrones de movimiento de los cazadores en bosques densos y a través de un terreno complejo. Analizamos estadísticamente las hipótesis sobre la distribución espacial de la cacería mediante una teoría de circuito y modelos de ecuaciones estructurales. Usamos un conjunto de datos de más de 7000 localidades conocidas de sacrificios en Guayana y los modelos de movimiento de los cazadores para probar estos modelos. La comparación entre modelos con diferentes capas de resistencia (es decir, diferentes estimaciones de cómo el terreno y la cobertura de suelo influyen sobre la velocidad del movimiento humano) mostró que los ríos, en promedio, limitaron el movimiento en lugar de funcionar como arterias de transporte. Además, ocurrieron mucho más sacrificios cerca de las aldeas que en las áreas remotas. Lo anterior, combinado con la falta de apoyo para los modelos de ecuaciones estructurales que incluyeron los términos latentes para la reducción de presas causada por la sobrecaza pasada, sugiere que las localidades de sacrificios en este sistema tendieron a ser seleccionadas por la ubicación actual en la que los cazadores se encontraban forrajeando y no por la influencia de la cosecha histórica. Estos análisis son generalizables para una variedad de ecosistemas, especies y tipos de datos, lo que proporciona una manera poderosa de mejorar los mapas y las predicciones de los esfuerzos de cacería a través de paisajes complejos.

Human-centered design process and solutions to promote malaria testing and treatment seeking behavior in Guyana hinterlands.

BACKGROUND: Malaria is a persistent public health challenge among miners and other hard-to-reach populations in Guyana's hinterland, specifically in Regions 1, 7, 8, and 9. Despite an overall decrease in malaria prevalence throughout Guyana, it remains common among mining populations whose work conditions both contribute toward malaria transmission and make it difficult to seek timely, Ministry of Health (MoH) approved malaria testing and treatment services. In an effort to develop innovative approaches to address this public health challenge, an interdisciplinary team of public health professionals, designers, and mining organizations collaborated using a human-centered design (HCD) process facilitated by the USAID-funded Breakthrough ACTION Guyana project in partnership with the MoH. METHODS: This paper describes two phases: [1] Define and [2] Design & Test. In the Define phase, following a literature review, we conducted 108 qualitative interviews with miners, camp managers, trained malaria testers, health workers, and other key stakeholders to understand experiences and challenges when seeking malaria testing and treatment services. These interviews were synthesized into 11 insights on issues such as risk perception, malaria knowledge, preventive behaviors, traditional and self-treatment, adherence to the correct treatment, testing, and coordination and communication gaps. From these insights, during the Design & Test phase, we developed 33 "How might we…?" questions which led to 792 ideas, of which eight emergent concepts were prototyped and refined in the field with 145 miners, camp managers, and stakeholders. RESULTS: The five final prototypes included: "Little Mosquito, Big Problem" social behavior change campaign; rapid counseling cards; branded malaria testing and treatment services; innovations in treatment adherence; and a participants, content, and logistics approach. CONCLUSION: When applying HCD to public health issues, there are both opportunities and challenges to reconcile gaps that may exist between the two disciplines. However, HCD provides additional tools and mindsets to generatively work with migrant and mobile mining communities to encourage malaria testing and treatment services.

Barriers to Prostate Cancer Screening Among Indo-Guyanese.

Prostate cancer is one of the most common types of cancer in many industrialized countries and is among the leading causes of death. Ranking among one of the top three forms of cancer, it is unfortunate that prostate cancer screening is not routinely recommended. This study attempts to explore the barriers to prostate cancer screening among Indo-Guyanese men. We conducted in-depth, one on one interviews among 20 Indo-Guyanese men between the ages of 45 and 75 years old, residing in the New York City neighborhood of Queens. Qualitative analysis was performed using multiple coders. Detailed analysis of the data found four major themes to be the culprit associated with a decrease in prostate cancer screening in this population: (1) lack of knowledge about the disease, (2) fear of diagnosis, (3) embarrassment and, (4) personal reservations with the rectal exam. The findings of this research suggest that Indo-Guyanese immigrants are lacking the basic understanding of prostate cancer and the importance of screening. It is possible that this deficiency is also applicable to many other disease states. By collaborating with healthcare providers and other stakeholders, such as community leaders and elected officials, we can develop culturally appropriate services specific to this population, to address these barriers to healthcare services.

Range extension of the miniature pencil-catfish Potamoglanis wapixana (Siluriformes: Trichomycteridae) into the Essequibo River basin, Guyana.

Morphological examination of Potamoglanis specimens from three localities in the Essequibo River basin, Guyana, and one location in the Branco River basin, Brazil, confirmed their identification as Potamoglanis wapixana - a species originally described from only the Branco River basin. Morphological similarity of these miniature catfishes on opposite sides of the Rupununi savannah watershed divide and new records from lentic habitat suggest that either their modern populations predate the Pliocene division of the Branco and Essequibo rivers or the species is capable of living in and/or migrating across the Rupununi Portal - a seasonally flooded hydrological connection known to facilitate the movement of mostly much larger fishes between the Branco and Essequibo basins.

Loricaria cuffyi (Siluriformes: Loricariidae), a new species of loricariin catfish from the Guiana Shield.

Loricaria cuffyi n. sp. is described based on 36 specimens from the Essequibo and upper Negro River drainages in western Guyana and the upper Orinoco River drainage in Venezuela. The new species can be distinguished from sympatric and geographically proximate congeners by a postorbital notch that is inconspicuous, shallow and rounded, odontode ridges on the dorsum of head and predorsal weakly developed, abdominal plates tightly joined and completely covering the median abdominal space and pectoral girdle, higher anterior lateral plate counts, and coloration characteristics. The distribution of the new species adds to an interesting and well-documented biogeographical pattern exhibited by other Guiana Shield loricariids influenced by the proto-Berbice during the Cenozoic and recent configuration of drainages in the Guiana Shield. We present an update on the taxonomy of Loricaria, and discuss the biogeography and conservation status of the new species.

Sorcery and well-being: bodily transformation at Beckeranta.

This paper examines bodily transformation and well-being within the context of a millenarian movement that emerged during the 1840s in the area surrounding Mount Roraima at the periphery of Brazil, Guyana (British Guiana at the time), and Venezuela. The site of this movement was Beckeranta - meaning 'Land of the Whites' - where up to 400 Amerindians were reportedly killed in a quest that is described in its sole historical account as centred around a goal of bodily transformation into white people. In examining this movement, the paper engages with longstanding debates in medical anthropology concerning the body, as well as conversations among Amazonianists concerning the social formation of bodies, and examines sorcery and shamanism as practices that go 'beyond the body'. Notions of bodily transformation in Amazonia, which are often activated by strong emotions, facilitate conceptual expansions of the body in medical anthropology. The paper suggests that bodily transformations tied to sorcery and shamanism are in some contexts, such as at Beckeranta, associated with desires for well-being.Supplemental data for this article is available online at https://doi.org/10.1080/13648470.2020.1807726.

[MRI of the axial skeleton for evaluation of prostate cancer extent in french Guyana]. / IRM du squelette axial pour le bilan du cancer de prostate en Guyane française.

INTRODUCTION: Spread evaluation of Prostate Cancer (PC) in French Guyana is bothered by the lack of bone scintigraphy. The availability of 4 MRI allows to develop alternatives using Axial Skeleton MRI (AS MRI). We report the related results. MATERIAL: AS MRI was done in patients with diagnosis of high risk PC: PSA>=10ng/ml and/or Gleason Score>=7 (predominant Gleason grade 4) and/or clinical T2b and/or T2b/T3 MRI and/or >50% positive biopsies. AS MRI was including spine, pelvis and skull assessement.The results were systematically compared to the clinical, biological and biopsy features. RESULTS: Amongst 163 AS MRI performed, 30 were positive and 133 negative. Of these 133 patients, 60 were submited to radical prostatectomy with or without lymphadenectomy. In these 133 patients with negative AS MRI, median PSA was 11ng/ml (1-51) and 27 (20,3%) had PSA>20ng/ml. In patients with positive AS MRI, only 1 had PSA<20ng/ml and predominant Gleason grade 3. CONCLUSION: Our study shows that AS MRI assessement is especially usefull in patients who are most likely to have bone metastasis that is to say those with PSA>20ng/ml and/or predominant Gleason grade 4. LEVEL OF EVIDENCE: 3.

The Cauxin-femme binary: Femme performativity as a response to violence in Guyana.

The Caribbean region has a long history of violence and conflict due to colonization and contemporary neocolonial policies and structures. The region's political, economic, and social climate is overshadowed by activism that centers legal repeal of homophobic laws left intact by colonial powers. These movements have created a polarization between the mainstream groups seeking legal changes, and those who are denied and erased from these discourses. This article is an examination of lesbian, bisexual, queer and gay women of mixed-race middle-class status in the city of Georgetown, Guyana as they negotiate racialized heteropatriarchal violence, a space that offers a unique place in which to understand how different queer subjects experience violence within Guyana. This article examines a set of interrelated questions: In what ways do women who love women perceive their gender performances? In what ways is femme-ness embodied to resist violence and yet is a site of violence? The analysis reveals the ways in which women embody a strategic femme-ness in a political, racial, class, and gender hierarchical society. As the country becomes increasingly incorporated into a global queer culture, divisions within the queer community are further sharpened, with racial, class, sexual, gender, and regional boundaries shifting and forging new lived realities for queer subjects.

Pseudoflowers produced by Fusarium xyrophilum on yellow-eyed grass (Xyris spp.) in Guyana: A novel floral mimicry system?

Pseudoflower formation is arguably the rarest outcome of a plant-fungus interaction. Here we report on a novel putative floral mimicry system in which the pseudoflowers are composed entirely of fungal tissues in contrast to modified leaves documented in previous mimicry systems. Pseudoflowers on two perennial Xyris species (yellow-eyed grass, X. setigera and X. surinamensis) collected from savannas in Guyana were produced by Fusarium xyrophilum, a novel Fusarium species. These pseudoflowers mimic Xyris flowers in gross morphology and are ultraviolet reflective. Axenic cultures of F. xyrophilum produced two pigments that had fluorescence emission maxima in light ranges that trichromatic insects are sensitive to and volatiles known to attract insect pollinators. One of the volatiles emitted by F. xyrophilum cultures (i.e., 2-ethylhexanol) was also detected in the head space of X. laxifolia var. iridifolia flowers, a perennial species native to the New World. Results of microscopic and PCR analyses, combined with examination of gross morphology of the pseudoflowers, provide evidence that the fungus had established a systemic infection in both Xyris species, sterilized them and formed fungal pseudoflowers containing both mating type idiomorphs. Fusarium xyrophilum cultures also produced the auxin indole-3-acetic acid (IAA) and the cytokinin isopentenyl adenosine (iPR). Field observations revealed that pseudoflowers and Xyris flowers were both visited by bees. Together, the results suggest that F. xyrophilum pseudoflowers are a novel floral mimicry system that attracts insect pollinators, via visual and olfactory cues, into vectoring its conidia, which might facilitate outcrossing of this putatively heterothallic fungus and infection of previously uninfected plants.

Digging for care-seeking behaviour among gold miners in the Guyana hinterland: a qualitative doer non-doer analysis of social and behavioural motivations for malaria testing and treatment.

BACKGROUND: Although Guyana has made significant progress toward malaria control, limited access to malaria testing and treatment services threatens those gains. Mining activities create breeding environments for mosquitoes, and the migrant and mobile mining populations are hard to reach with information and services. The Ministry of Public Health (MoPH) has trained volunteers to test and treat malaria cases in remote regions. However, it remains unclear how miners perceive these testers, the services they provide, or what their malaria care-seeking behaviour is in general. To better address these challenges, Breakthrough ACTION Guyana and MoPH conducted qualitative research from October to November 2018 in Regions 7 and 8 in Guyana. METHODS: A total of 109 individuals, 70 miners, 17 other mining camp staff, and 22 other key stakeholders (e.g. community health workers, pharmacists, and regional leadership), participated in semi-structured interviews and focus group discussions. Results were derived using a framework analysis, with an adjusted doer and non-doer analysis, and organized using the integrated behaviour framework. RESULTS: Miners sought MoPH-approved services because of close geographic proximity to testing services, a preference for public service treatment, and a desire to correctly diagnose and cure malaria rather than just treat its symptoms. Those who chose to initiate self-treatment-using unregulated medications from the private and informal sector-did so out of convenience and the belief that self-treatment had worked before. Miners who completed the full MoPH-approved treatment understood the need to complete the treatment, while those who prematurely stopped treatment did so because of medication side effects and a desire to feel better as soon as possible. CONCLUSION: Reasons why miners do and do not pursue malaria testing and treatment services are diverse. These results can inform better MoPH programming and new solutions to improve malaria outcomes in Guyana.

Anibamine and Its Analogues: Potent Antiplasmodial Agents from Aniba citrifolia.

In our continuing search for novel natural products with antiplasmodial activity, an extract of Aniba citrifolia was found to have good activity, with an IC50 value less than 1.25 µg/mL. After bioassay-directed fractionation, the known indolizinium alkaloid anibamine (1) and the new indolizinium alkaloid anibamine B (2) were isolated as the major bioactive constituents, with antiplasmodial IC50 values of 0.170 and 0.244 µM against the drug-resistant Dd2 strain of Plasmodium falciparum. The new coumarin anibomarin A (3), the new norneolignan anibignan A (5), and six known neolignans (7-12) were also obtained. The structures of all the isolated compounds were determined based on analyses of 1D and 2D NMR spectroscopic and mass spectrometric data, and the absolute configuration of anibignan A (5) was assigned from its ECD spectrum. Evaluation of a library of 28 anibamine analogues (13-40) indicated that quaternary charged analogues had IC50 values as low as 58 nM, while uncharged analogues were inactive or significantly less active. Assessment of the potential effects of anibamine and its analogues on the intraerythrocytic stages and morphological development of P. falciparum revealed substantial activity against ring stages for compounds with two C-10 side chains, while those with only one C-10 side chain exhibited substantial activity against trophozoite stages, suggesting different mechanisms of action.