The Madagascar National Strategic Plan for Malaria Control 2018 (NSP) outlines malaria control pre-elimination strategies that include detailed goals for mosquito control. Primary surveillance ...protocols and mosquito control interventions focus on indoor vectors of malaria, while many potential vectors feed and rest outdoors. Here we describe the application of tools that advance our understanding of diversity, host choice, and Plasmodium infection in the Anopheline mosquitoes of the Western Highland Fringe of Madagascar.
We employed a modified barrier screen trap, the QUadrant Enabled Screen Trap (QUEST), in conjunction with the recently developed multiplex BLOOdmeal Detection Assay for Regional Transmission (BLOODART). We captured a total of 1252 female Anopheles mosquitoes (10 species), all of which were subjected to BLOODART analysis. QUEST collection captured a heterogenous distribution of mosquito density, diversity, host choice, and Plasmodium infection. Concordance between Anopheles morphology and BLOODART species identifications ranged from 93-99%. Mosquito feeding behavior in this collection frequently exhibited multiple blood meal hosts (single host = 53.6%, two hosts = 42.1%, three hosts = 4.3%). The overall percentage of human positive bloodmeals increased between the December 2017 and the April 2018 timepoints (27% to 44%). Plasmodium positivity was frequently observed in the abdomens of vectors considered to be of secondary importance, with an overall prevalence of 6%.
The QUEST was an efficient tool for sampling exophilic Anopheline mosquitoes. Vectors considered to be of secondary importance were commonly found with Plasmodium DNA in their abdomens, indicating a need to account for these species in routine surveillance efforts. Mosquitoes exhibited multiple blood feeding behavior within a gonotrophic cycle, with predominantly non-human hosts in the bloodmeal. Taken together, this complex feeding behavior could enhance the role of multiple Anopheline species in malaria transmission, possibly tempered by zoophilic feeding tendencies.
Anopheles mosquitoes employ complex behavioral and physiological strategies to adapt to their environment. Here we show how altering the number of bites a mosquito takes per gonotrophic cycle ...(gonotrophic discordance) could raise the transmission potential of a mosquito population far above model predictions.
Understanding how climate and land cover currently shape species distributions and community structure is crucial to inform conservation decisions. Unfortunately, limited information is available for ...the relative importance of climatic and land use variables in determining the distribution of amphibians and reptiles. Here, we studied amphibian and reptile communities from the Carpathian Mountains, asking (i) to what extent is the distribution of reptiles and amphibians determined by environmental gradients, (ii) does the response to these factors differ between amphibians and reptiles, and (iii) are reptile and amphibian communities at higher altitudes more similar to each other than communities from lower altitudes. We found that forests, pastures, and heterogeneous arable land best explain the composition of the herpetofauna, with mountain communities associated with coniferous forests, and lowland species with mixed or broad-leaved forests and pastures. Our results also suggest that reptiles and amphibians respond idiosyncratically to the influence of climate and land use. Reptiles responded more to land use and less to climate variables compared with amphibians. Of the three amphibian hybrids registered, one (
Bombina
) was associated with heterogeneous arable land. These results have potential implications for future conservation planning, especially in the light of global climate change and changes in land use. Hence, local and regional processes are important in shaping amphibian and reptile communities.
mosquitoes vary in habitat preference, feeding pattern, and susceptibility to various measures of vector control. Consequently, it is important that we identify reservoirs of disease, identify ...vectors, and characterize feeding patterns to effectively implement targeted control measures. Using 467 anopheline mosquito abdomen squashes captured in Madagascar, we designed a novel ligase detection reaction and fluorescent microsphere assay, dubbed Bloodmeal Detection Assay for Regional Transmission (BLOODART), to query the bloodmeal content, identify five
mosquito species, and detect
infection. Validation of mammalian bloodspots was achieved by preparation and analysis of known hosts (singular and mixed), sensitivity to degradation and storage method were assessed through mosquito feeding experiments, and quantification was explored by altering ratios of two mammal hosts. BLOODART identifications were validated by comparison with mosquito samples identified by sequenced portions of the internal transcribed spacer 2. BLOODART identification of control mammal bloodspots was 100% concordant for singular and mixed mammalian blood. BLOODART was able to detect hosts up to 42 hours after digestion when mosquito samples were stored in ethanol. A mammalian host was identified in every field-collected, blood-fed female
mosquito by BLOODART. The predominant mosquito host was cow (
= 451), followed by pig (
= 26) and human (
= 25). Mixed species bloodmeals were commonly observed (
= 33). A BLOODART molecular identification was successful for 318/467 mosquitoes, with an overall concordance of 60% with all field-captured, morphologically identified
specimens. BLOODART enables characterization of large samples and simultaneous pathogen detection to monitor and incriminate disease vectors in Madagascar.
Current malaria rapid diagnostic tests (RDTs) contain antibodies against
-specific histidine-rich protein 2 (PfHRP2),
lactate dehydrogenase (pLDH), and aldolase in various combinations. Low or high ...parasite densities/target antigen concentrations may influence the accuracy and sensitivity of PfHRP2-detecting RDTs. We analyzed the SD Bioline Malaria Ag P.f/Pan RDT performance in relation to
parasitemia in Madagascar, where clinical
malaria exists alongside
. Nine hundred sixty-three samples from patients seeking care for suspected malaria infection were analyzed by RDT, microscopy, and
species-specific, ligase detection reaction-fluorescent microsphere assay (LDR-FMA).
infection positivity by these diagnostics was 47.9%, 46.9%, and 58%, respectively.
-only infections were predominant (microscopy, 45.7%; LDR-FMA, 52.3%). In all, 16.3% of
, 70% of
, and all of
,
, and mixed-species infections were submicroscopic. In 423
mono-infections, confirmed by microscopy and LDR-FMA, the parasitemia in those who were positive for both the PfHRP2 and pan-pLDH test bands was significantly higher than that in those who were positive only for the PfHRP2 band (
< 0.0001).
parasitemia in those that were detected as
-only infections by microscopy but
mixed infections by LDR-FMA also showed similar outcome by the RDT band positivity. In addition, we used varying parasitemia (3-0.0001%) of the laboratory-maintained 3D7 strain to validate this observation. A positive pLDH band in high
-parasitemic individuals may complicate diagnosis and treatment, particularly when the microscopy is inconclusive for
, and the two infections require different treatments.
Anthropogenic activity often results in habitat fragmentation that can negatively impact biodiversity by destroying viable habitat and reducing the connectivity of the landscape. Anthropogenic ...features (such as rail ways) can also have the opposite effect, facilitating the expansion of certain species. Here we demonstrate such a case, wherein anthropogenic activity and structures facilitate the dispersal of a species whose capacity for territorial expansion is limited in the natural environment. Using habitat suitability and connectivity models, we show that the Common Wall Lizard (Podarcis muralis) most likely prefers railways as a means to disperse into new habitats and/or maintain population connectivity across a fragmented habitat (i.e. from their southern populations, moving north along rail way tracks to colonize new suitable habitats). Furthermore, we predict the route and location of future colonization events based on availability of viable habitats and corridors to them. The potential impact of this invasion is estimated to be relatively low.
•Fragmented landscapes are often passed by railways or roads.•Common Wall Lizards are able to use the railways to expand their range.•Rivers are also significant ecological corridors that aid species ranges shifts.•Active and passive dispersal means are jointly used in range expansions.
A recent targeted entomological survey in the Republic of Rwanda has produced two conspecific male and female specimens of an undescribed species of praying mantis (Mantodea). The specimens were ...collected in Nyungwe National Park in May of 2013. The species is closest morphologically to Dystacta alticeps (Schaum, 1853). Therefore, a new species is described, Dystacta tigrifrutex sp. n., along with the first instar nymphs and ootheca. In addition, the previously monotypic genus Dystacta Saussure, 1871 is re-described to provide a broader definition of the genus group. Habitus images, measurement data, a key to species, natural history information, and locality data are provided.
Malaria continues to be a persistent threat to the health of Madagascar’s people. Effective control necessitates efficient vector surveillance. Laxity has lethal consequences. Mosquito control across ...the island has historically focused on reduction of, and protection from, malaria vectors that feed and rest indoors. In spite of evidence suggesting that outdoor resting and feeding mosquitoes could be involved in malaria transmission in this county, surveillance protocols continue to emphasize endophilic vectors, leaving gaps in our understanding of the role of exophilic mosquitoes.We deployed a modified barrier screen trap, the QUEST (QUadrant Enabled Screen Trap), in conjunction with a novel assay we call BLOODART (BLOOdmeal Detection Assay for Regional Transmission) to sample exophilic vectors in the Madagascar Highland Fringe. We captured a total of 1252 female Anopheles mosquitoes (10 species), all of which were subjected to BLOODART analysis. QUEST collection produced a heterogenous distribution of mosquito density, diversity, host choice, and Plasmodium infection. The mosquitoes in this collection frequently exhibited multiple blood feeding behavior (MBF) (46.4%), and a shift in the overall percentage of humanpositive bloodmeals from December 2017 to April 2018 (27% to 44%). Plasmodium positivity (prevalence = 6%) was found primarily in vectors considered to be of secondary importance, indicating a need to account for these species in routine surveillance efforts.We modeled the potential impact of multiple blood feeding behavior on common transmission metrics, including the entomological inoculation rate, the vectorial capacity, and the proportion of living infectious vectors in a mosquito population. These models suggest that multiple host contact could act as a force multiplier for malaria transmission.
We report the results of two surveys targeting praying mantises in four localities in Rwanda, specifically Akagera National Park, Nyungwe National Park, Volcanoes National Park, and the Arboretum de ...Ruhande at the National University of Rwanda. Using an assortment of collecting techniques, including metal halide light traps, sweep netting vegetation and general searching, we obtained 387 adult and 352 juvenile specimens, representing 41 species. A total of 28 novel species records for Rwanda are added to the 18 previously recorded species for the country, in addition to 20 novel species records for the broader region, including neighbouring Uganda and Burundi. This study provides high resolution images of the dorsal habitus of both sexes of representative species, both pinned and living. Species distribution records are presented and discussed. With a 155% increase in species recorded from Rwanda, this survey illustrates the need for further taxonomic work in the region.
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