ZooTraits: An R shiny app for exploring animal trait data for ecological and evolutionary research.

Animal trait data are scattered across several datasets, making it challenging to compile and compare trait information across different groups. For plants, the TRY database has been an unwavering success for those ecologists interested in addressing how plant traits influence a wide variety of processes and patterns, but the same is not true for most animal taxonomic groups. Here, we introduce ZooTraits, a Shiny app designed to help users explore and obtain animal trait data for research in ecology and evolution. ZooTraits was developed to tackle the challenge of finding in a single site information of multiple trait datasets and facilitating access to traits by providing an easy-to-use, open-source platform. This app combines datasets centralized in the Open Trait Network, raw data from the AnimalTraits database, and trait information for animals compiled by Gonçalves-Souza et al. (2023, Ecology and Evolution 13, e10016). Importantly, the ZooTraits app can be accessed freely and provides a user-friendly interface through three functionalities that will allow users to easily visualize, compare, download, and upload trait data across the animal tree of life-ExploreTrait, FeedTrait, and GetTrait. By using ExploreTrait and GetTrait, users can explore, compare, and extract 3954 trait records from 23,394 species centralized in the Open Traits Network, and trait data for ~2000 species from the AnimalTraits database. The app summarizes trait information for numerous taxonomic groups within the Animal Kingdom, encompassing data from diverse aquatic and terrestrial ecosystems and various geographic regions worldwide. Moreover, ZooTraits enables researchers to upload trait information, serving as a hub for a continually expanding global trait database. By promoting the centralization of trait datasets and offering a platform for data sharing, ZooTraits is facilitating advancements in trait-based ecological and evolutionary studies. We hope that other trait databases will evolve to mirror the approach we have outlined here.

Forest cover percentage drives the peak biting time of Nyssorhynchus darlingi (Diptera: Culicidae) in the Brazilian Amazon.

BACKGROUND: Deforestation is an important driver of malaria dynamics, with a relevant impact on mosquito ecology, including larval habitat availability, blood-feeding behaviour, and peak biting time. The latter is one of several entomological metrics to evaluate vectorial capacity and effectiveness of disease control. This study aimed to test the effect of forest cover percentage on the peak biting time of Plasmodium-uninfected and infected Nyssorhynchus darlingi females. METHODS: Mosquitoes were captured utilizing human landing catch (HLC) in the peridomestic habitat in field collections carried out in the wet, wet-dry transition, and dry seasons from 2014 to 2017 in areas with active malaria transmission in Amazonian Brazil. The study locations were in rural settlements in areas with the mean annual malaria parasite incidence (Annual Parasite Incidence, API ≥ 30). All Ny. darlingi females were tested for Plasmodium spp. infection using real time PCR technique. Forest cover percentage was calculated for each collection site using QGIS v. 2.8 and was categorized in three distinct deforestation scenarios: (1) degraded, < 30% forest cover, (2) intermediate, 30-70% forest cover, and (3) preserved, > 70% forest cover. RESULTS: The highest number of uninfected female Ny. darlingi was found in degraded landscape-sites with forest cover < 30% in any peak biting time between 18:00 and 0:00. Partially degraded landscape-sites, with (30-70%) forest cover, showed the highest number of vivax-infected females, with a peak biting time of 21:00-23:00. The number of P. falciparum-infected mosquitoes was highest in preserved sites with > 70% forest cover, a peak biting at 19:00-20:00, and in sites with 30-70% forest cover at 22:00-23:00. CONCLUSIONS: Results of this study show empirically that degraded landscapes favour uninfected Ny. darlingi with a peak biting time at dusk (18:00-19:00), whereas partially degraded landscapes affect the behaviour of Plasmodium-infected Ny. darlingi by shifting its peak biting time towards hours after dark (21:00-23:00). In preserved sites, Plasmodium-infected Ny. darlingi bite around dusk (18:00-19:00) and shortly after (19:00-20:00).

Mutations Linked to Insecticide Resistance Not Detected in the Ace-1 or VGSC Genes in Nyssorhynchus darlingi from Multiple Localities in Amazonian Brazil and Peru.

Indoor residual spray (IRS), mainly employing pyrethroid insecticides, is the most common intervention for preventing malaria transmission in many regions of Latin America; the use of long-lasting insecticidal nets (LLINs) has been more limited. Knockdown resistance (kdr) is a well-characterized target-site resistance mechanism associated with pyrethroid and DDT resistance. Most mutations detected in acetylcholinesterase-1 (Ace-1) and voltage-gated sodium channel (VGSC) genes are non-synonymous, resulting in a change in amino acid, leading to the non-binding of the insecticide. In the present study, we analyzed target-site resistance in Nyssorhynchus darlingi, the primary malaria vector in the Amazon, in multiple malaria endemic localities. We screened 988 wild-caught specimens of Ny. darlingi from three localities in Amazonian Peru and four in Amazonian Brazil. Collections were conducted between 2014 and 2021. The criteria were Amazonian localities with a recent history as malaria hotspots, primary transmission by Ny. darlingi, and the use of both IRS and LLINs as interventions. Fragments of Ace-1 (456 bp) and VGSC (228 bp) were amplified, sequenced, and aligned with Ny. darlingi sequences available in GenBank. We detected only synonymous mutations in the frequently reported Ace-1 codon 280 known to confer resistance to organophosphates and carbamates, but detected three non-synonymous mutations in other regions of the gene. Similarly, no mutations linked to insecticide resistance were detected in the frequently reported codon (995) at the S6 segment of domain II of VGSC. The lack of genotypic detection of insecticide resistance mutations by sequencing the Ace-1 and VGSC genes from multiple Ny. darlingi populations in Brazil and Peru could be associated with low-intensity resistance, or possibly the main resistance mechanism is metabolic.

Biodiversity is overlooked in the diets of different social groups in Brazil.

Food biodiversity is essential for improving nutrition and reducing hunger in populations worldwide. However, in middle and low-income countries, the biodiversity of food production does not necessarily represent food consumption patterns by population. We used Brazil, one of the world's megabiodiverse countries, as a case study to investigate the following questions: what is the prevalence of consumption of biodiverse foods in Brazil, and what are the socioeconomic factors that influence their consumption throughout the country? We used data from a Brazilian representative national dietary survey to estimate the frequency of food consumption of unconventional food plants, edible mushrooms, and wild meat, in according to socioeconomic variables. Thus, we investigated the socioeconomic predictors of Unconventional Food Plants consumption using methods of Machine Learning (ML) and multiple zero-inflated Poisson (ZIP) regression. We showed that biodiverse food consumption in Brazil is low, just related by 1.3% of the population, varying in according to area, ethnicity, age, food insecurity, sex, and educational level. Our findings of low utilization of biodiversity suggest an important mismatch between the rich biodiversity of the country and its representation in the human diet.

Bringing light onto the Raunkiæran shortfall: A comprehensive review of traits used in functional animal ecology.

Trait-based approaches elucidate the mechanisms underlying biodiversity response to, or effects on, the environment. Nevertheless, the Raunkiæran shortfall-the dearth of knowledge on species traits and their functionality-presents a challenge in the application of these approaches. We conducted a systematic review to investigate the trends and gaps in trait-based animal ecology in terms of taxonomic resolution, trait selection, ecosystem type, and geographical region. In addition, we suggest a set of crucial steps to guide trait selection and aid future research to conduct within and cross-taxon comparisons. We identified 1655 articles using virtually all animal groups published from 1999 to 2020. Studies were concentrated in vertebrates, terrestrial habitats, the Palearctic realm, and mostly investigated trophic and habitat dimensions. Additionally, they focused on response traits (79.4%) and largely ignored intraspecific variation (94.6%). Almost 36% of the data sets did not provide the rationale behind the selection of morphological traits. The main limitations of trait-based animal ecology were the use of trait averages and a rare inclusion of intraspecific variability. Nearly one-fifth of the studies based only on response traits conclude that trait diversity impacts ecosystem processes or services without justifying the connection between them or measuring them. We propose a guide for standardizing trait collection that includes the following: (i) determining the type of trait and the mechanism linking the trait to the environment, ecosystem, or the correlation between the environment, trait, and ecosystem, (ii) using a "periodic table of niches" to select the appropriate niche dimension to support a mechanistic trait selection, and (iii) selecting the relevant traits for each retained niche dimension. By addressing these gaps, trait-based animal ecology can become more predictive. This implies that future research will likely focus on collaborating to understand how environmental changes impact animals and their capacity to provide ecosystem services and goods.

Treatment patterns, healthcare resource utilization and costs of HER2-negative gastric/gastroesophageal junction cancer.

Aim: To describe treatment patterns, healthcare resource utilization and costs in HER2-negative gastric/gastroesophageal (G/GEJ) cancer in the USA. Methods: Retrospective IQVIA Adjudicated Closed Claims database analysis; patients with HER2-negative G/GEJ cancer initiating systemic therapy between October 2016 and December 2019 were identified. Results: Among 1317 patients, platinum plus taxane regimens (54%) were common in neoadjuvant/adjuvant settings. Platinum-taxane (41%) and platinum-fluoropyrimidine (36%) regimens were common first-line therapies in the metastatic setting. Treatment regimens were heterogeneous in later lines. Hospitalization rates ranged from 39% (first-, second-line metastatic settings) to 61% (neoadjuvant/adjuvant setting). High healthcare resource utilization was driven by high outpatient costs. Mean per-patient per-month outpatient costs combining physician office and hospital visits ranged from US$10,944 to $12,582 (representing 52-70% of total costs). Conclusion: For G/GEJ cancer, systemic regimens varied across lines of therapy with variation increasing with subsequent therapy lines; high healthcare costs persist for systemic treatment, particularly outpatient services.

The cost impact of disease progression to metastatic castration-sensitive prostate cancer.

BACKGROUND: Metastatic prostate cancer (PC) is associated with declining survival rates and increased health care expenditure. However, there are few studies quantifying these increased costs. OBJECTIVE: To estimate overall health care resource utilization and costs associated with progression to metastatic disease in Medicare or commercially insured patients with nonmetastatic castration-sensitive PC (nmCSPC) or previously undiagnosed PC. METHODS: In this retrospective, observational cohort study, we used data from the IBM MarketScan Commercial and MarketScan Medicare Supplemental Databases. Included patients were aged 18 years or older, had 2 or more health care claims associated with a diagnosis of PC, and had a diagnosis of metastatic disease (index date) between January 1, 2014, and December 31, 2016. Patients with PC were identified at index as either progressing from a localized disease state (nmCSPC) without evidence of castration resistance (progressors) or de novo metastatic without a prior PC diagnosis. Unadjusted all-cause direct health care costs for the 2-year pre-index period and up to 2 years post-index were summarized. Metastasis-related incremental all-cause direct health care costs were estimated using regression modeling to adjust for patient baseline characteristics, follow-up duration, and possible selection bias. RESULTS: We identified 3,854 patients who met the criteria for CSPC at metastasis: 2,766 Medicare patients (mean age 78.8 ± 7.6 years) and 1,088 commercial patients (mean age 57.6 ± 4.3 years), with de novo patients accounting for 28.9% and 34.5% of the 2 analysis populations, respectively. Mean unadjusted total all-cause health care costs over the 24-month pre-index period among progressors were $52,661 (Medicare) and $43,111 (commercial); those among de novo patients were $39,756 (Medicare) and $22,090 (commercial). Mean unadjusted post-index costs for progressors were $100,331 (Medicare) and $127,374 (commercial) over a mean follow-up duration of 14.63 and 18.41 months, respectively, and $124,538 (Medicare) and $173,408 (commercial) over a mean follow-up duration of 14.14 and 17.29 months for patients with de novo disease. After multivariate adjustment, incremental cost increases due to metastasis in patients with CSPC pre-index were estimated at $104,051 (Medicare) and $93,334 (commercial), assuming data are available for 24 months post-index. Allowing for variation in the postindex observation period, estimates were $71,308 (Medicare) and $82,336 (commercial). Among de novo patients, cost increases due to metastasis were estimated at $180,932 (Medicare) and $215,397 (commercial), assuming all patients have data for 24 months postindex. Allowing for variable follow-up, estimates were $113,253 (Medicare) and $161,714 (commercial). CONCLUSIONS: Development of metastatic CSPC is associated with considerable costs over a 24-month follow-up period. Cost increases are greater for de novo patients than for those who progressed from localized disease. DISCLOSURES: Q.-D. Trinh received personal fees from Astellas, Bayer, and Janssen and grants from Intuitive Surgical. L. Passos Chaves, Q. Feng, J. Zhu, and T. Abbott are employees of Astellas Pharma Global Development, Inc. R. Sandin is an employee of, and holds stock in, Pfizer AB. This study was funded by Astellas Pharma Inc. (Northbrook, IL) and Pfizer Inc., the codevelopers of enzalutamide. Astellas Pharma Inc. was involved in the study design, data collection, analysis, interpretation of data, and decision to present these results.

Vector role and human biting activity of Anophelinae mosquitoes in different landscapes in the Brazilian Amazon.

BACKGROUND: Environmental disturbance, deforestation and socioeconomic factors all affect malaria incidence in tropical and subtropical endemic areas. Deforestation is the major driver of habitat loss and fragmentation, which frequently leads to shifts in the composition, abundance and spatial distribution of vector species. The goals of the present study were to: (i) identify anophelines found naturally infected with Plasmodium; (ii) measure the effects of landscape on the number of Nyssorhynchus darlingi, presence of Plasmodium-infected Anophelinae, human biting rate (HBR) and malaria cases; and (iii) determine the frequency and peak biting time of Plasmodium-infected mosquitoes and Ny. darlingi. METHODS: Anopheline mosquitoes were collected in peridomestic and forest edge habitats in seven municipalities in four Amazon Brazilian states. Females were identified to species and tested for Plasmodium by real-time PCR. Negative binomial regression was used to measure any association between deforestation and number of Ny. darlingi, number of Plasmodium-infected Anophelinae, HBR and malaria. Peak biting time of Ny. darlingi and Plasmodium-infected Anophelinae were determined in the 12-h collections. Binomial logistic regression measured the association between presence of Plasmodium-infected Anophelinae and landscape metrics and malaria cases. RESULTS: Ninety-one females of Ny. darlingi, Ny. rangeli, Ny. benarrochi B and Ny. konderi B were found to be infected with Plasmodium. Analysis showed that the number of malaria cases and the number of Plasmodium-infected Anophelinae were more prevalent in sites with higher edge density and intermediate forest cover (30-70%). The distance of the drainage network to a dwelling was inversely correlated to malaria risk. The peak biting time of Plasmodium-infected Anophelinae was 00:00-03:00 h. The presence of Plasmodium-infected mosquitoes was higher in landscapes with > 13 malaria cases. CONCLUSIONS: Nyssorhynchus darlingi, Ny. rangeli, Ny. benarrochi B and Ny. konderi B can be involved in malaria transmission in rural settlements. The highest fraction of Plasmodium-infected Anophelinae was caught from midnight to 03:00 h. In some Amazonian localities, the highest exposure to infectious bites occurs when residents are sleeping, but transmission can occur throughout the night. Forest fragmentation favors increases in both malaria and the occurrence of Plasmodium-infected mosquitoes in peridomestic habitat. The use of insecticide-impregnated mosquito nets can decrease human exposure to infectious Anophelinae and malaria transmission.

Malaria transmission in landscapes with varying deforestation levels and timelines in the Amazon: a longitudinal spatiotemporal study.

The relationship between deforestation and malaria is a spatiotemporal process of variation in Plasmodium incidence in human-dominated Amazonian rural environments. The present study aimed to assess the underlying mechanisms of malarial exposure risk at a fine scale in 5-km2 sites across the Brazilian Amazon, using field-collected data with a longitudinal spatiotemporally structured approach. Anopheline mosquitoes were sampled from 80 sites to investigate the Plasmodium infection rate in mosquito communities and to estimate the malaria exposure risk in rural landscapes. The remaining amount of forest cover (accumulated deforestation) and the deforestation timeline were estimated in each site to represent the main parameters of both the frontier malaria hypothesis and an alternate scenario, the deforestation-malaria hypothesis, proposed herein. The maximum frequency of pathogenic sites occurred at the intermediate forest cover level (50% of accumulated deforestation) at two temporal deforestation peaks, e.g., 10 and 35 years after the beginning of the organization of a settlement. The incidence density of infected anophelines in sites where the original forest cover decreased by more than 50% in the first 25 years of settlement development was at least twice as high as the incidence density calculated for the other sites studied (adjusted incidence density ratio = 2.25; 95% CI, 1.38-3.68; p = 0.001). The results of this study support the frontier malaria as a unifying hypothesis for explaining malaria emergence and for designing specific control interventions in the Brazilian Amazon.

Anthropogenic landscape decreases mosquito biodiversity and drives malaria vector proliferation in the Amazon rainforest.

Inter-relationships among mosquito vectors, Plasmodium parasites, human ecology, and biotic and abiotic factors, drive malaria risk. Specifically, rural landscapes shaped by human activities have a great potential to increase the abundance of malaria vectors, putting many vulnerable people at risk. Understanding at which point the abundance of vectors increases in the landscape can help to design policies and interventions for effective and sustainable control. Using a dataset of adult female mosquitoes collected at 79 sites in malaria endemic areas in the Brazilian Amazon, this study aimed to (1) verify the association among forest cover percentage (PLAND), forest edge density (ED), and variation in mosquito diversity; and to (2) test the hypothesis of an association between landscape structure (i.e., PLAND and ED) and Nyssorhynchus darlingi (Root) dominance. Mosquito collections were performed employing human landing catch (HLC) (peridomestic habitat) and Shannon trap combined with HLC (forest fringe habitat). Nyssorhynchus darlingi abundance was used as the response variable in a generalized linear mixed model, and the Shannon diversity index (H') of the Culicidae community, PLAND, and the distance house-water drainage were used as predictors. Three ED categories were also used as random effects. A path analysis was used to understand comparative strengths of direct and indirect relationships among Amazon vegetation classes, Culicidae community, and Ny. darlingi abundance. Our results demonstrate that Ny. darlingi is negatively affected by H´ and PLAND of peridomestic habitat, and that increasing these variables (one-unit value at ß0 = 768) leads to a decrease of 226 (P < 0.001) and 533 (P = 0.003) individuals, respectively. At the forest fringe, a similar result was found for H' (ß1 = -218; P < 0.001) and PLAND (ß1 = -337; P = 0.04). Anthropogenic changes in the Amazon vegetation classes decreased mosquito biodiversity, leading to increased Ny. darlingi abundance. Changes in landscape structure, specifically decreases in PLAND and increases in ED, led to Ny. darlingi becoming the dominant species, increasing malaria risk. Ecological mechanisms involving changes in landscape and mosquito species composition can help to understand changes in the epidemiology of malaria.

Host feeding patterns of Nyssorhynchus darlingi (Diptera: Culicidae) in the Brazilian Amazon.

Nyssorhynchus darlingi (Root) is the dominant malaria vector in the Brazilian Amazon River basin, with additional Anophelinae Grassi species involved in local and regional transmission. Mosquito blood-feeding behavior is an essential component to define the mosquito-human contact rate and shape the transmission cycle of vector-borne diseases. However, there is little information on the host preferences and blood-feeding behavior of Anophelinae vectors in rural Amazonian landscapes. The barrier screen sampling (BSS) method was employed to sample females from 34 peridomestic habitats in 27 rural communities from 11 municipalities in the Brazilian Amazon states of Acre, Amazonas, Pará and Rondônia, from August 2015 to November 2017. Nyssorhynchus darlingi comprised 97.94% of the females collected resting on barrier screens, and DNA sequence comparison detected 9 vertebrate hosts species. The HBI index ranged from 0.03-1.00. Results revealed the plasticity of Ny. darlingi in blood-feeding on a wide range of mainly mammalian hosts. In addition, the identification of blood meal sources using silica-dried females is appropriate for studies of human malaria vectors in remote locations.

The risk of malaria infection for travelers visiting the Brazilian Amazonian region: A mathematical modeling approach.

BACKGROUND: Human mobility between malaria endemic and malaria-free areas can hinder control and elimination efforts in the Amazon basin, maintaining Plasmodium circulation and introduction to new areas. METHODS: The analysis begins by estimating the incidence of malaria in areas of interest. Then, the risk of infection as a function of the duration of stay after t0 was calculated as the number of infected travelers over the number of arrived travelers. Differential equations were employed to estimate the risk of nonimmune travelers acquiring malaria in Amazonian municipalities. Risk was calculated as a result of the force of the infection in terms of local dynamics per time of arrival and duration of visit. RESULTS: Maximum risk occurred at the peak or at the end of the rainy season and it was nonlinearly (exponentially) correlated with the fraction of infected mosquitoes. Relationship between the risk of malaria and duration of visit was linear and positively correlated. Relationship between the risk of malaria and the time of arrival in the municipality was dependent on local effects of seasonality. CONCLUSIONS: The risk of nonimmune travelers acquiring malaria is not negligible and can maintain regional circulation of parasites, propagating introductions in areas where malaria has been eliminated.

The environmental footprint of health care: a global assessment.

BACKGROUND: Health-care services are necessary for sustaining and improving human wellbeing, yet they have an environmental footprint that contributes to environment-related threats to human health. Previous studies have quantified the carbon emissions resulting from health care at a global level. We aimed to provide a global assessment of the wide-ranging environmental impacts of this sector. METHODS: In this multiregional input-output analysis, we evaluated the contribution of health-care sectors in driving environmental damage that in turn puts human health at risk. Using a global supply-chain database containing detailed information on health-care sectors, we quantified the direct and indirect supply-chain environmental damage driven by the demand for health care. We focused on seven environmental stressors with known adverse feedback cycles: greenhouse gas emissions, particulate matter, air pollutants (nitrogen oxides and sulphur dioxide), malaria risk, reactive nitrogen in water, and scarce water use. FINDINGS: Health care causes global environmental impacts that, depending on which indicator is considered, range between 1% and 5% of total global impacts, and are more than 5% for some national impacts. INTERPRETATION: Enhancing health-care expenditure to mitigate negative health effects of environmental damage is often promoted by health-care practitioners. However, global supply chains that feed into the enhanced activity of health-care sectors in turn initiate adverse feedback cycles by increasing the environmental impact of health care, thus counteracting the mission of health care. FUNDING: Australian Research Council, National eResearch Collaboration Tools and Resources project.

Evolutionary aspects that guide the cultural transmission pathways in a local medical system in Northeast Brazil.

Most of the studies with a focus on pathways and biases of cultural transmission in different domains show that vertical transmission predominates over horizontal and oblique transmission, especially in traits linked to traditions and survival skills, such as local medicine. However, overestimation of the importance of vertical transmission has been an object of methodological criticism. Therefore, a statistical analysis with diachronic perspective may obtain more accurate results. The present study uses an eight-year time frame, as well as synchronous analysis, to study evolutionary aspects that guide the transmission pathways of a local medical system in northeast Brazil. We find that even with vertical transmission being predominant in the learning of information in this cultural domain, the evolutionary implications of this predominance may not be the same as that expected by the theory of cultural evolution. There is a substantial updating of knowledge through horizontal and oblique routes, guided primarily by a model-based bias on prestige and success, which is quite adaptive. Moreover, even when the information is passed vertically, the transmission is much more diffusive than conservative. Indeed, there is a small set of information that remains over time, known as a "structural core," but new information is aggregated continuously, preparing the system to adapt to new events. By analyzing the transmission routes of knowledge about medicinal plants, this study presents a new perspective on the evolutionary implications of cultural transmission.

Hunters' preferences and perceptions as hunting predictors in a semiarid ecosystem.

Game meat is a resource widely exploited by rural populations in various parts of the world. In recent decades, the growth in the number of people living near conserved areas has increased the demand for game meat. In this work, based on the Social-ecological Theory of Maximization, we seek to verify the influence of cost-benefit ratio, availability, and subjective preferences (flavor) in the selection of hunted species. We interviewed game-eating people in seven communities in the Brazilian semiarid region, recording information on hunting strategies, flavor preferences, and relative abundance of game fauna. We found that people hunt for the most available species regardless of the cost-benefit of this choice. Also, flavor preference can increase the odds of a species being hunted almost 100%. Our data show that hunters may prefer species that require less capture effort, even though they have energy-efficient alternatives. We found that flavor preference is proportionally the variable with the most significant effect on the chances of a species being hunted, suggesting that traditional optimal foraging models are too simple to cover the complexity involved in the selection of game species.

Global consumption and international trade in deforestation-associated commodities could influence malaria risk.

Deforestation can increase the transmission of malaria. Here, we build upon the existing link between malaria risk and deforestation by investigating how the global demand for commodities that increase deforestation can also increase malaria risk. We use a database of trade relationships to link the consumption of deforestation-implicated commodities in developed countries to estimates of country-level malaria risk in developing countries. We estimate that about 20% of the malaria risk in deforestation hotspots is driven by the international trade of deforestation-implicated export commodities, such as timber, wood products, tobacco, cocoa, coffee and cotton. By linking malaria risk to final consumers of commodities, we contribute information to support demand-side policy measures to complement existing malaria control interventions, with co-benefits for reducing deforestation and forest disturbance.

Vector competence, vectorial capacity of Nyssorhynchus darlingi and the basic reproduction number of Plasmodium vivax in agricultural settlements in the Amazonian Region of Brazil.

BACKGROUND: Brazilian malaria control programmes successfully reduced the incidence and mortality rates from 2005 to 2016. Since 2017, increased malaria has been reported across the Amazon. Few field studies focus on the primary malaria vector in high to moderate endemic areas, Nyssorhynchus darlingi, as the key entomological component of malaria risk, and on the metrics of Plasmodium vivax propagation in Amazonian rural communities. METHODS: Human landing catch collections were carried out in 36 houses of 26 communities in five municipalities in the Brazilian states of Acre, Amazonas and Rondônia states, with API (> 30). In addition, data on the number of locally acquired symptomatic infections were employed in mathematical modelling analyses carried out to determine Ny. darlingi vector competence and vectorial capacity to P. vivax; and to calculate the basic reproduction number for P. vivax. RESULTS: Entomological indices and malaria metrics ranged among localities: prevalence of P. vivax infection in Ny. darlingi, from 0.243% in Mâncio Lima, Acre to 3.96% in Machadinho D'Oeste, Rondônia; daily human-biting rate per person from 23 ± 1.18 in Cruzeiro do Sul, Acre, to 66 ± 2.41 in Lábrea, Amazonas; vector competence from 0.00456 in São Gabriel da Cachoeira, Amazonas to 0.04764 in Mâncio Lima, Acre; vectorial capacity from 0.0836 in Mâncio Lima, to 1.5 in Machadinho D'Oeste. The estimated R0 for P. vivax (PvR0) was 3.3 in Mâncio Lima, 7.0 in Lábrea, 16.8 in Cruzeiro do Sul, 55.5 in São Gabriel da Cachoeira, and 58.7 in Machadinho D'Oeste. Correlation between P. vivax prevalence in Ny. darlingi and vector competence was non-linear whereas association between prevalence of P. vivax in mosquitoes, vectorial capacity and R0 was linear and positive. CONCLUSIONS: In spite of low vector competence of Ny. darlingi to P. vivax, parasite propagation in the human population is enhanced by the high human-biting rate, and relatively high vectorial capacity. The high PvR0 values suggest hyperendemicity in Machadinho D'Oeste and São Gabriel da Cachoeira at levels similar to those found for P. falciparum in sub-Saharan Africa regions. Mass screening for parasite reservoirs, effective anti-malarial drugs and vector control interventions will be necessary to shrinking transmission in Amazonian rural communities, Brazil.

Exploring malaria vector diversity on the Amazon Frontier.

BACKGROUND: Deforestation in the Amazon and the social vulnerability of its settler communities has been associated with increased malaria incidence. The feeding biology of the most important malaria vectors in the region, notably Nyssorhynchus darlingi, compounds efforts to control vectors and reduce transmission of what has become known as "Frontier Malaria". Exploring Anophelinae mosquito diversity is fundamental to understanding the species responsible for transmission and developing appropriate management and intervention strategies for malaria control in the Amazon River basin. METHODS: This study describes Anophelinae mosquito diversity from settler communities affected by Frontier Malaria in the states of Acre, Amazonas and Rondônia by analysing COI gene data using cluster and tree-based species delimitation approaches. RESULTS: In total, 270 specimens from collection sites were sequenced and these were combined with 151 reference (GenBank) sequences in the analysis to assist in species identification. Conservative estimates found that the number of species collected at these sites was between 23 (mPTP partition) and 27 (strict ABGD partition) species, up to 13 of which appeared to be new. Nyssorhynchus triannulatus and Nyssorhynchus braziliensis displayed exceptional levels of intraspecific genetic diversity but there was little to no support for putative species complex status. CONCLUSIONS: This study demonstrates that Anophelinae mosquito diversity continues to be underestimated in poorly sampled areas where frontier malaria is a major public health concern. The findings will help shape future studies of vector incrimination and transmission dynamics in these areas and support efforts to develop more effective vector control and transmission reduction strategies in settler communities in the Amazon River basin.