Interpreting mosquito feeding patterns in Australia through an ecological lens; an analysis of blood meal studies.

Mapping Intimacies ◽

10.1101/492934 ◽

2018 ◽

Author(s):

Eloise B Stephenson ◽

Amanda Murphy ◽

Cassie C Jansen ◽

Alison J Peel ◽

Hamish McCallum

Keyword(s):

Blood Meal ◽

Disease Transmission ◽

Disease Ecology ◽

Mosquito Species ◽

Meta Analysis ◽

Feeding Patterns ◽

Larval Habitats ◽

Culex Annulirostris ◽

Species Specific ◽

The Impact

Mosquito-borne pathogens contribute significantly to the global burden of disease, infecting millions of people each year. Mosquito feeding is critical to the transmission dynamics of pathogens, and thus it is important to understanding and interpreting mosquito feeding patterns. In this paper we explore mosquito feeding patterns and their implications for disease ecology through a meta-analysis of published blood meal results collected across Australia from more than 12,000 blood meals from 22 species. To assess mosquito-vertebrate associations and identify mosquitoes on a spectrum of generalist or specialist feeders, we analysed blood meal data in two ways; first using a novel odds ratio analysis, and secondly by calculating Shannon diversity scores. We find that each mosquito species had a unique feeding association with different vertebrates, suggesting species-specific feeding patterns. Broadly, mosquito species could be grouped broadly into those that were primarily ornithophilic and those that fed more often on livestock. Aggregated feeding patterns observed across Australia were not explained by intrinsic variables such as mosquito genetics or larval habitats. We discuss the implications for disease transmission by vector mosquito species classified as generalist-feeders (such as Aedes vigilax and Culex annulirostris), or specialists (such as Aedes aegypti) in light of potential influences on mosquito host choice. Overall, we find that whilst existing blood meal studies in Australia are useful for investigating mosquito feeding patterns, standardisation of blood meal study methodologies and analyses, including the incorporation of vertebrate surveys, would improve predictions of the impact of vector-host interactions on disease ecology. Our analysis can also be used as a framework to explore mosquito-vertebrate associations, in which host availability data is unavailable, in other global systems.

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Rapid ageing and species identification of natural mosquitoes for malaria surveillance

10.1101/2020.06.11.144253 ◽

2020 ◽

Author(s):

Doreen J. Siria ◽

Roger Sanou ◽

Joshua Mitton ◽

Emmanuel P. Mwanga ◽

Abdoulaye Niang ◽

...

Keyword(s):

Mosquito Species ◽

Natural Populations ◽

Cost Effective ◽

Malaria Vectors ◽

Sampling Effort ◽

Malaria Surveillance ◽

Vector Borne Diseases ◽

Vector Borne ◽

Species Specific ◽

The Impact

AbstractThe malaria parasite, which is transmitted by several Anopheles mosquito species, requires more time to reach its human-transmissible stage than the average lifespan of a mosquito. Monitoring the species-specific age structure of mosquito populations is critical to evaluating the impact of vector control interventions on malaria risk. We developed a rapid, cost-effective surveillance method based on deep learning of mid-infrared spectra of mosquitoes’ cuticle that simultaneously identifies the species and the age of three main malaria vectors, in natural populations. Using over 40,000 ecologically and genetically diverse females, we could speciate and age grade An. gambiae, An. arabiensis, and An. coluzzii with up to 95% accuracy. Further, our model learned the age of new populations with minimal sampling effort and detected the impact of control interventions on simulated mosquito populations, measured as a shift in their age structures. We anticipate our method to be applied to other arthropod vector-borne diseases.

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School reopening and risks accelerating the COVID-19 pandemic: A systematic review and meta-analysis protocol

PLoS ONE ◽

10.1371/journal.pone.0260189 ◽

2021 ◽

Vol 16 (11) ◽

pp. e0260189

Author(s):

Luís Carlos Lopes-Júnior ◽

Priscila Carminati Siqueira ◽

Ethel Leonor Noia Maciel

Keyword(s):

Systematic Review ◽

Potential Risk ◽

Disease Transmission ◽

Meta Analysis ◽

Random Effect ◽

Random Effect Model ◽

Cochrane Library ◽

British Library ◽

The Impact ◽

Analysis Protocol

Background One of the most recent concerns of this pandemic regards the role of schools reopening in disease transmission, as well as the impact of keeping schools closed. While school reopening seems critical for the education and mental health of children, adolescents, and adults, so far the literature has not systematically reached a consensus whether to recommend the return to schools in a way that would be safe for students and staff. Objective To synthesize and critically evaluate the scientific evidence on the potential risk of accelerating the Coronavirus Disease 2019 (COVID-19) pandemic among children, adolescents, young adults, and adults with school reopening. Methods This systematic review and meta-analysis protocol was elaborated following the PRISMA-P. We will include all observational study designs, which report on the potential risk of accelerating the COVID-2019 pandemic with school reopening. Electronic databases included were MEDLINE/PubMed, Cochrane Library, EMBASE, Web of Science, SCOPUS and CNKI. Additional sources will be also retrieved, including Clinical trials.gov-NIH, The British Library, Pro Quest Dissertations Database, Public Health Gray Literature Sources and Health Evidence, Google Scholar, and pre-prints [medRXiv]. No restriction to language or date will be used as search strategy. In an independently manner, two investigators will select studies, perform data extraction, as well as perform a critical appraisal of the risk of bias and overall quality of the selected observational studies, based on their designs. The heterogeneity among the studies will be assessed using the I2 statistic test. According to the results of this test, we will verify whether a meta-analysis is feasible. If feasibility is confirmed, a random-effect model analysis will be carried out. For data analysis, the calculation of the pooled effect estimates will consider a 95% CI and alpha will be set in 0.05 using the R statistical software, v.4.0.4. In addition, we will rate the certainty of evidence based on Cochrane methods and in accordance with the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Expected results This systematic review and meta-analysis will provide better insights into safety in the return to school in the context of the COVID-2019 pandemic, at a time when vaccination advances unevenly in several countries around the world. Hence, consistent data and robust evidence will be provided to help decision-makers and stakeholders in the current pandemic scenario. PROSPERO registration number CRD42021265283; https://clinicaltrials.gov.

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Chemical parameters and bacterial communities associated with larval habitats of Anopheles, Culex and Aedes mosquitoes (Diptera: Culicidae) in western Kenya

International Journal of Tropical Insect Science ◽

10.1017/s1742758416000096 ◽

2016 ◽

Vol 36 (03) ◽

pp. 146-160 ◽

Cited By ~ 11

Author(s):

Thomas Ogao Onchuru ◽

Yvonne Ukamaka Ajamma ◽

Marion Burugu ◽

Martin Kaltenpoth ◽

Daniel Masiga ◽

...

Keyword(s):

Disease Transmission ◽

Bacterial Communities ◽

Mosquito Species ◽

Species Abundance ◽

Larval Habitat ◽

Mosquito Vector ◽

Endemic Region ◽

Western Kenya ◽

Larval Habitats ◽

16S Rrna Pyrosequencing

AbstractAquatic larval habitat conditions influence the development, fitness and vectorial capacity of mosquitoes. In turn, human activities can influence these conditions and shape mosquito vector distribution, thus affecting pathogen circulation and transmission. We measured environmental factors (chemical and microbial) in mosquito larval habitats and evaluated their potential as predictors for the occurrence of different mosquito species in an arbovirus and malaria endemic region of western Kenya. We found significantly greater proportions ofAedes aegyptimosquito larvae in ammonium and phosphate rich habitats, suggesting that fertilizer usage could potentially increase aquatic habitat suitability andAedesvectored disease transmission.Anopheles gambiaelarval habitats correlated significantly with higher temperatures. However, none of theCulexspecies’ habitats correlated with investigated variables, indicating greater larval plasticity compared toAedesorAnopheles. Profiling of bacterial communities by 16S rRNA pyrosequencing revealed Proteobacteria, Bacterioidetes and Firmicutes as the major bacteria phyla present in mosquito aquatic microhabitats. Although there were no correlations between microbiota composition or diversity and larval species abundance, the dominant genera of microbes detected in larval habitats were reported in larval and adult mid-guts, suggesting that bacteria acquired from the larval habitats are transmitted to adult stages. This study identified the chemical and bacterial composition of aquatic microhabitats that are conducive to the development of different mosquito vectors in western Kenya. This information can inform potential vector control strategies by assessing management of breeding sites based on likely exposure to fertilizer, light and bacterial fauna.

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Assessing the blood meal hosts of Culex quinquefasciatus and Aedes taeniorhynchus in Isla Santa Cruz, Galápagos

Parasites & Vectors ◽

10.1186/s13071-019-3835-7 ◽

2019 ◽

Vol 12 (1) ◽

Author(s):

Samoa Asigau ◽

Sawsan Salah ◽

Patricia G. Parker

Keyword(s):

Feeding Behavior ◽

Culex Quinquefasciatus ◽

Blood Meal ◽

Disease Transmission ◽

Avian Malaria ◽

Mosquito Species ◽

Blood Feeding ◽

Santa Cruz ◽

Aedes Taeniorhynchus ◽

Blood Meals

Abstract Background Blood meal host selection by mosquito vectors is an important component in understanding disease dynamics of pathogens that threaten endemic fauna in isolated islands such as Galápagos. Research on the feeding behavior of mosquitoes can provide clues to the hosts and vectors involved in disease transmission. This information is particularly critical for endemic wildlife fauna in island systems that have evolved without resistance to novel diseases such as avian malaria. The aims of this study were to determine the blood-feeding patterns of two species of mosquitoes found in Galápagos and discuss how their feeding behavior may influence the transmission of pathogens such as avian malaria. Methods In the summer of 2015, we sampled two mosquito species (Aedes taeniorhynchus and Culex quinquefasciatus) across 18 different sites on Isla Santa Cruz, which is the second largest island in Galápagos and has the largest human population. We trapped mosquitoes using CDC light traps and CDC gravid traps and identified sources of blood meals for engorged mosquitoes by sequencing a portion of the vertebrate mitochondrial cytochrome b gene. Results Out of 947 female mosquitoes captured, 320 were blood-fed, and PCR amplifications were successful for 301 of the blood meals. Results revealed that both Aedes taeniorhynchus and Culex quinquefasciatus feed from a variety of vertebrate taxa, numerically dominated by humans on Isla Santa Cruz. Conclusions The high proportion of mammalian blood meals could represent locally available and abundant hosts on Santa Cruz. However, host surveys and estimates of relative abundances of vertebrate species will need to accompany mosquito trapping studies on non-inhabited and inhabited islands in Galápagos to further validate this.

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Dehydration bouts prompt increased activity and blood feeding by mosquitoes

10.1101/120741 ◽

2017 ◽

Author(s):

Richard W. Hagan ◽

Elise M. Szuter ◽

Andrew E. Rosselot ◽

Christopher J. Holmes ◽

Samantha C. Siler ◽

...

Keyword(s):

Water Loss ◽

Disease Transmission ◽

Disease Modeling ◽

Mosquito Species ◽

Blood Feeding ◽

Dehydration Stress ◽

Terrestrial Invertebrates ◽

The Difference ◽

General Response ◽

The Impact

AbstractMosquitoes are prone to dehydration and respond to this stress through multiple mechanisms, but previous studies have examined very specific responses and fail to provide an encompassing view of the role that dehydration has on mosquito biology. This study examined underlying changes in biology of the northern house mosquito, Culex pipiens, associated with short bouts of dehydration. We show that dehydration increased blood feeding propensity of mosquitoes, which was the result of both enhanced activity and a higher tendency to land on a host. Mosquitoes exposed to dehydrating conditions with access to water or rehydrated individuals experience no water loss and failed to display behavioral changes. RNA-seq and metabolome analyses following dehydration indicated that factors associated with energy metabolism are altered, specifically the breakdown of trehalose to yield glucose, which likely underlies changes in mosquito activity. Suppression of trehalose breakdown by RNA interference reduced phenotypes associated with dehydration. Comparable results were noted for two other mosquito species, suggesting this is a general response among mosquitoes. Lastly, field-based mesocosm studies using C. pipiens revealed that dehydrated mosquitoes were more likely to host feed, and disease modeling indicates dehydration bouts may increase transmission of West Nile virus. These results suggest that periods of dehydration prompt mosquitoes to utilize blood feeding as a mechanism to obtain water. This dehydration-induced increase in blood feeding is likely to intensify disease transmission during periods of low water availability.SignificanceDehydration stress has substantial impacts on the biology of terrestrial invertebrates. To date, no studies have elucidated the difference between dehydration exposure and realized water loss in relation to mosquito behavior and physiology. Our experiments show that direct dehydration stress increases mosquito activity and subsequent blood feeding, likely as a mechanism to locate and utilize a bloodmeal for rehydration. These dehydration-induced phenotypes were linked to altered carbohydrate metabolism that acts as a source of energy. This study provides important insight into the impact of mosquito-dehydration dynamics on disease transmission that is likely general among mosquitoes.

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Infected Mosquitoes Have Altered Behavior to Repellents: A Systematic Review and Meta-analysis

Journal of Medical Entomology ◽

10.1093/jme/tjz209 ◽

2019 ◽

Vol 57 (2) ◽

pp. 542-550

Author(s):

Marc J Lajeunesse ◽

Daniel A Avello ◽

Morgan S Behrmann ◽

Thomas J Buschbacher ◽

Kayla Carey ◽

...

Keyword(s):

Systematic Review ◽

Plasmodium Berghei ◽

Disease Transmission ◽

Odds Ratio ◽

Sindbis Virus ◽

Protective Efficacy ◽

Mosquito Species ◽

Meta Analysis ◽

Human Contact ◽

Period Effects

Abstract Here we conducted a systematic review and meta-analysis to reach a consensus on whether infected and uninfected mosquitoes respond differently to repellents. After screening 2,316 published studies, theses, and conference abstracts, we identified 18 studies that tested whether infection status modulated the effectiveness of repellents. Thirteen of these studies had outcomes available for meta-analysis, and overall, seven repellents were tested (typically DEET with 62% of outcomes), six mosquito species had repellence behaviors measured (typically Aedes aegypti (L.) (Diptera: Culicidae) mosquitoes with 71% of outcomes), and a broad diversity of infections were tested including Sindbis virus (Togaviridae: Alphavirus) (33% of outcomes), Dengue (Flaviviridae: Flavivirus) (31%), malaria (Plasmodium berghei Vincke & Lips (Haemospororida: Plasmodiidae) or P. falciparum Welch (Haemospororida: Plasmodiidae); 25%), Zika (Flaviviridae: Flavivirus) (7%), and microsporidia (4%). Pooling all outcomes with meta-analysis, we found that repellents were less effective against infected mosquitoes—marking an average 62% reduction in protective efficacy relative to uninfected mosquitoes (pooled odds ratio = 0.38, 95% confidence interval = 0.22–0.66; k = 96). Older infected mosquitoes were also more likely to show altered responses and loss of sensitivity to repellents, emphasizing the challenge of distinguishing between age or incubation period effects. Plasmodium- or Dengue-infected mosquitoes also did not show altered responses to repellents; however, Dengue–mosquito systems used inoculation practices that can introduce variability in repellency responses. Given our findings that repellents offer less protection against infected mosquitoes and that these vectors are the most dangerous in terms of disease transmission, then trials on repellent effectiveness should incorporate infected mosquitoes to improve predictability in blocking vector–human contact.

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Randomized trials of housing interventions to prevent malaria and Aedes-transmitted diseases: A systematic review and meta-analysis

PLoS ONE ◽

10.1371/journal.pone.0244284 ◽

2021 ◽

Vol 16 (1) ◽

pp. e0244284

Author(s):

Kok Pim Kua ◽

Shaun Wen Huey Lee

Keyword(s):

Systematic Review ◽

Disease Transmission ◽

Randomized Trials ◽

Meta Analysis ◽

Intervention Group ◽

Public Health Problem ◽

Future Research ◽

Cochrane Central Register ◽

Secondary Outcomes ◽

The Impact

Background Mosquito-borne diseases remain a significant public health problem in tropical regions. Housing improvements such as screening of doors and windows may be effective in reducing disease transmission, but the impact remains unclear. Objectives To examine whether housing interventions were effective in reducing mosquito densities in homes and the impact on the incidence of mosquito-borne diseases. Methods In this systematic review and meta-analysis, we searched 16 online databases, including NIH PubMed, CINAHL Complete, LILACS, Ovid MEDLINE, and Cochrane Central Register of Controlled Trials for randomized trials published from database inception to June 30, 2020. The primary outcome was the incidence of any mosquito-borne diseases. Secondary outcomes encompassed entomological indicators of the disease transmission. I2 values were used to explore heterogeneity between studies. A random-effects meta-analysis was used to assess the primary and secondary outcomes, with sub-group analyses for type of interventions on home environment, study settings (rural, urban, or mixed), and overall house type (traditional or modern housing), Results The literature search yielded 4,869 articles. After screening, 18 studies were included in the qualitative review, of which nine were included in the meta-analysis. The studies enrolled 7,200 households in Africa and South America, reporting on malaria or dengue only. The type of home environmental interventions included modification to ceilings and ribbons to close eaves, screening doors and windows with nets, insecticide-treated wall linings in homes, nettings over gables and eaves openings, mosquito trapping systems, metal-roofed houses with mosquito screening, gable windows and closed eaves, and prototype houses using southeast Asian designs. Pooled analysis depicted a lower risk of mosquito-borne diseases in the housing intervention group (OR = 0.68; 95% CI = 0.48 to 0.95; P = 0.03). Subgroup analysis depicted housing intervention reduced the risk of malaria in all settings (OR = 0.63; 95% CI = 0.39 to 1.01; P = 0.05). In urban environment, housing intervention was found to decrease the risk of both malaria and dengue infections (OR = 0.52; 95% CI = 0.27 to 0.99; P = 0.05).Meta-analysis of pooled odds ratio showed a significant benefit of improved housing in reducing indoor vector densities of both Aedes and Anopheles (OR = 0.35; 95% CI = 0.23 to 0.54; P<0.001). Conclusions Housing intervention could reduce transmission of malaria and dengue among people living in the homes. Future research should evaluate the protective effect of specific house features and housing improvements associated with urban development.

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Comparative account of energy reserves in four co-occurring mosquito species in Kolkata, India (Diptera: Culicidae)

Polish Journal of Entomology ◽

10.1515/pjen-2017-0004 ◽

2017 ◽

Vol 86 (1) ◽

pp. 49-67

Author(s):

Sushree Mohan ◽

Sampa Banerjee ◽

Soujita Pramanik ◽

Soumyajit Banerjee ◽

Goutam K. Saha ◽

...

Keyword(s):

Life History ◽

Disease Transmission ◽

Function Analysis ◽

Mosquito Species ◽

Resource Acquisition ◽

Life History Strategies ◽

Adult Survival ◽

Pupal Weight ◽

Energy Reserves ◽

Species Specific

AbstractEnergy reserves in mosquitoes are an indicator of fitness, linking larval effort in resource acquisition with adult survival and fecundity. In other words, life history strategies and disease transmission potential can be related to the amount of energy reserves. The energy reserves of four mosquitoes –Aedes aegypti, Aedes albopictus, Armigeres subalbatusandCulex quinquefasciatus(Diptera: Culicidae) – were calculated to justify species-specific differences in their life history strategies. Following repeated sampling of pupae from the respective larval habitats, the glycogen, sugar and lipid contents of individual mosquitoes were assessed and corroborated with pupal weight and adult wing length. Discriminant function analysis was used to acquire an initial reflection of the differences of the parameters among the sex and species of the mosquitoes considered in the study. Using logistic regression and ANOVA, the effects of species and sex as contributors to variations in energy reserves could be established. The results indicated that for all the mosquitoes, sex-specific differences were prominent with reference to the energy reserves. Species-specific differences in energy reserves reflect differences in resource acquisition and assimilation in the tissues, and thus the differences in the life history strategies of these four species.

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