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1. Aedes albopictus host odor preference does not drive observed variation in feeding patterns across field populations

   https://doi.org/10.1038/s41598-022-26591-3  

   Fikrig, Kara; Rose, Noah; Burkett-Cadena, Nathan; Kamgang, Basile; Leisnham, Paul T.; Mangan, Jamie; Ponlawat, Alongkot; Rothman, Sarah E.; Stenn, Tanise; McBride, Carolyn S.; et al (December 2023, Scientific Reports)

   Abstract Laboratory and field-based studies of the invasive mosquito Aedes albopictus demonstrate its competency to transmit over twenty different pathogens linked to a broad range of vertebrate hosts. The vectorial capacity of Ae. albopictus to transmit these pathogens remains unclear, partly due to knowledge gaps regarding its feeding behavior. Blood meal analyses from field-captured specimens have shown vastly different feeding patterns, with a wide range of anthropophagy (human feeding) and host diversity. To address this knowledge gap, we asked whether differences in innate host preference may drive observed variation in Ae. albopictus feeding patterns in nature. Low generation colonies (F2–F4) were established with field-collected mosquitoes from three populations with high reported anthropophagy (Thailand, Cameroon, and Florida, USA) and three populations in the United States with low reported anthropophagy (New York, Maryland, and Virginia). The preference of these Ae. albopictus colonies for human versus non-human animal odor was assessed in a dual-port olfactometer along with control Ae. aegypti colonies already known to show divergent behavior in this assay. All Ae. albopictus colonies were less likely (p < 0.05) to choose the human-baited port than the anthropophilic Ae. aegypti control, instead behaving similarly to zoophilic Ae. aegypti . Our results suggest that variation in reported Ae. albopictus feeding patterns are not driven by differences in innate host preference, but may result from differences in host availability. This work is the first to compare Ae. albopictus and Ae. aegypti host preference directly and provides insight into differential vectorial capacity and human feeding risk. 

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2. The effects of urbanization, temperature, and rainfall on Aedes aegypti and Aedes albopictus mosquito abundance across a broad latitudinal gradient in Central Africa

   https://doi.org/10.1186/s13071-025-06764-5  

   Montgomery, Matthew_J; Harwood, James_F; Yougang, Aurelie_P; Wilson-Bahun, Théodel_A; Tedjou, Armel_N; Keumeni, Christophe_Rostand; Wondji, Charles_S; Kamgang, Basile; Kilpatrick, A_Marm (April 2025, Parasites & Vectors)

   Abstract BackgroundUrbanization can influence disease vectors by altering larval habitat, microclimates, and host abundance. The global increase in urbanization, especially in Africa, is likely to alter vector abundance and pathogen transmission. We investigated the effect of urbanization and weather on the abundance of two mosquitoes,Aedes aegyptiandAedes albopictus, and infection with dengue, chikungunya, and Zika viruses at 63 sites in six cities spanning a 900-km latitudinal range in Cameroon, Central Africa. MethodsWe used human landing catches and backpack-mounted aspirators to sample mosquitoes and collected larval habitat, host availability, and weather (temperature, precipitation, humidity) data for each site in each city. We analyzed land use and land cover information and satellite photos at varying radii around sites (100 m to 2 km) to quantify the extent of urbanization and the number of structures around each site. We used a continuous urbanization index (UI; range 0–100) that increased with impermeable surface and decreased with forest cover. ResultsUrbanization increased larval habitat, human host availability, andAe. aegyptimosquito abundance.Aedes aegyptiabundance increased 1.7% (95% CI 0.69–2.7%) with each 1 unit increase in the urbanization index in all six cities (Douala, Kribi, Yaounde, Ngaoundere, Garoua, and Maroua) with a 5.4-fold increase from UI = 0 to UI = 100, and also increased with rainfall. In contrast,Ae. albopictusabundance increased with urbanization in one city, but showed no influence of urbanization in two other cites. Across three cities,Ae. albopictusabundance increased with rainfall, temperature, and humidity. Finally, we did not detect Zika, dengue, or chikungunya viruses in any specimens, and found weak evidence of interspecific competition in analyses of adult population growth rates. ConclusionsThese results show that urbanization consistently increasesAe. aegyptiabundance across a broad range of habitats in Central Africa, while effects onAe. albopictuswere more variable and the abundance of both species were influenced by rainfall. Future urbanization of Africa will likely increaseAe. aegyptiabundance, and climate change will likely alter abundance of both species through changes in precipitation and temperature. Graphical Abstract 

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3. Aedes albopictus Body Size Differs Across Neighborhoods With Varying Infrastructural Abandonment

   https://doi.org/10.1093/jme/tjz170  

   Katz, Grace; Leisnham, Paul T; LaDeau, Shannon L; Fonseca, Dina (October 2019, Journal of Medical Entomology)

   Abstract Mosquitoes pose an increasing risk in urban landscapes, where spatial heterogeneity in juvenile habitat can influence fine-scale differences in mosquito density and biting activity. We examine how differences in juvenile mosquito habitat along a spectrum of urban infrastructure abandonment can influence the adult body size of the invasive tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae). Adult Ae. albopictus were collected across 3 yr (2015–2017) from residential blocks in Baltimore, MD, that varied in abandonment level, defined by the proportion of houses with boarded-up doors. We show that female Ae. albopictus collected from sites with higher abandonment were significantly larger than those collected from higher income, low abandonment blocks. Heterogeneity in mosquito body size, including wing length, has been shown to reflect differences in important traits, including longevity and vector competence. The present work demonstrates that heterogeneity in female size may reflect juvenile habitat variability across the spatial scales most relevant to adult Aedes dispersal and human exposure risk in urban landscapes. Previous work has shown that failure to manage abandonment and waste issues in impoverished neighborhoods supports greater mosquito production, and this study suggests that mosquitoes in these same neighborhoods could live longer, produce more eggs, and have different vector potential. 

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4. Ecological drivers of dog heartworm transmission in California

   https://doi.org/10.1186/s13071-022-05526-x  

   Couper, Lisa I.; Mordecai, Erin A. (October 2022, Parasites & Vectors)

   Abstract BackgroundEffectively controlling heartworm disease—a major parasitic disease threatening animal health in the US and globally—requires understanding the local ecology of mosquito vectors involved in transmission. However, the key vector species in a given region are often unknown and challenging to identify. Here we investigate (i) the key vector species associated with transmission of the parasite,Dirofilaria immitis, in California and (ii) the climate and land cover drivers of vector presence. MethodsTo identify key mosquito vectors involved in transmission, we incorporated long-term, finely resolved mosquito surveillance data and dog heartworm case data in a statistical modeling approach (fixed-effects regression) that rigorously controls for other unobserved drivers of heartworm cases. We then used a flexible machine learning approach (gradient boosted machines) to identify the climate and land cover variables associated with the presence of each species. ResultsWe found significant, regionally specific, positive associations between dog heartworm cases and the abundance of four vector species:Aedes aegypti(Central California),Ae. albopictus(Southern California),Ae. sierrensis(Central California), andCuliseta incidens(Northern and Central California). The proportion of developed land cover was one of the most important ecological variables predicting the presence or absence of the putative vector species. ConclusionOur results implicate three previously under-recognized vectors of dog heartworm transmission in California and indicate the land cover types in which each putative vector species is commonly found. Efforts to target these species could prioritize surveillance in these land cover types (e.g. near human dwellings in less urbanized settings forAe. albopictusandCs. incidens) but further investigation on the natural infection prevalence and host-biting rates of these species, as well as the other local vectors, is needed. Graphical Abstract 

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5. A regional One Health approach to the risk of invasion by Anopheles stephensi in Mauritius

   https://doi.org/10.1371/journal.pntd.0011827  

   Iyaloo, Diana P; Zohdy, Sarah; Carney, Ryan M; Mosawa, Varina Ramdonee; Elahee, Khouaildi B; Munglee, Nabiihah; Latchooman, Nilesh; Puryag, Surendra; Bheecarry, Ambicadutt; Bhoobun, Hemant; et al (September 2024, PLOS Neglected Tropical Diseases)

   Christofferson, Rebecca C (Ed.)

   BackgroundAnopheles stephensiis an invasive malaria vector in Africa that threatens to put an additional 126 million people at risk of malaria if it continues to spread. The island nation of Mauritius is highly connected to Asia and Africa and is at risk of introduction due to this connectivity. For early detection ofAn.stephensi, the Vector Biology and Control Division under the Ministry of Health in Mauritius, leveraged a well-establishedAedesprogram, asAn.stephensiis known to shareAedeshabitats. These efforts triggered multisectoral coordination and cascading benefits of integrated vector and One Health approaches. MethodsBeginning June 2021, entomological surveys were conducted at points of entry (seaport, airport) and on ships transporting livestock in collaboration with the Civil Aviation Department, the Mauritian Port Authority and National Veterinary Services.A total of 18, 39, 723 mosquito larval surveys were respectively conducted in the airport, seaport, and other localities in Mauritius while two, 20, and 26 adult mosquito surveys were respectively conducted in the airport, seaport, and twenty-six animal assembly points. Alongside adult mosquito surveys, surveillance of vectors of veterinary importance (e.g.-Culicoidesspp.) was also carried out in collaboration with National Parks and Conservation Service and land owners. ResultsA total of 8,428 adult mosquitoes were collected and 1,844 larval habitats were positive for mosquitoes. All collected mosquitoes were morphologically identified and 151Anophelesand 339Aedesmosquitoes were also molecularly characterized. Mosquito species detected wereAedes albopictus,Anopheles arabiensis,An.coustani,An.merus,Culex quinquefasciatus,Cx.thalassiusandLutzia tigripes.Anopheles stephensiwas not detected. The One Health approach was shared with the French Agricultural Research Centre for International Development (CIRAD), strengthening collaboration between Mauritius and Réunion Island on vector surveillance at entry points and insecticide resistance monitoring. The Indian Ocean Commission (IOC) was also alerted to the risk ofAn.stephensi, leading to regional efforts supporting trainings and development of a response strategy toAn.stephensibringing together stakeholders from Comoros, Madagascar, Mauritius, Réunion Island and Seychelles. ConclusionsMauritius is a model system showing how existing public health entomology capabilities can be used to enhance vector surveillance and control and create multisectoral networks to respond to any emerging public and veterinary health vector-borne disease threat. 

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