key: cord-0882146-2ox8708a authors: Stone, Chris M title: Highlights of Medical Entomology, 2020 date: 2021-08-03 journal: J Med Entomol DOI: 10.1093/jme/tjab103 sha: dba62979110ecbaafa978c3a958c15d69bf42473 doc_id: 882146 cord_uid: 2ox8708a Medical Entomology as a field is inherently global – thriving on international and interdisciplinary collaborations and affected dramatically by arthropod and pathogen invasions and introductions. This past year also will be remembered as the year in which the SARS-CoV-2 COVID-19 pandemic affected every part of our lives and professional activities and impacted (or changed, sometimes in good ways) our ability to collaborate and detect or respond to invasions. This incredible year is the backdrop for the 2020 Highlights in Medical Entomology. This article highlights the broad scope of approaches and disciplines represented in the 2020 published literature, ranging from sensory and chemical ecology, population genetics, impacts of human-mediated environmental change on vector ecology, life history and the evolution of vector behaviors, to the latest developments in vector surveillance and control. The 2020 Annual Meeting of the Entomological Society of America and the Medical, Urban, and Veterinary Entomology section meetings were held virtually as a consequence of the ongoing SARS-CoV-2 pandemic. The effects of the pandemic on our field have been profound and will likely play out for years to come, as a result of demands on public health stakeholders' time (and in some cases, funding) being diverted to the COVID-19 response, and the broader implications of the impact on researcher's wellbeing and time. Reduced ability to continue with laboratory and fieldwork will affect research output in coming years, potentially with a shift to reviews and other types of analytical publications that are more conducive to working-from-home. Due to demands on the health care system, it is also possible that reported case numbers of vector-borne diseases will appear to dip. Repercussions of people spending more time in and around their home due to stay-at-home orders on vector-borne disease transmission are still unclear. Studies that have reported effects of lockdowns on dengue transmission appear to be quite variable (Brady and Wilder-Smith 2021) . Control and elimination programs of vector-borne diseases will be affected to varying extents (Toor et al. 2021) . In other words, challenges to medical entomology have only become more pronounced. It appears especially worthwhile then to survey our field in 2020, with much of the output reflecting research projects that were started before the pandemic, and highlight a subset of publications that represent particularly exciting steps forward. This article is by no means exhaustive or comprehensive, and is strongly biased toward papers I personally thought were exciting, elegant, and noteworthy. The screening of articles was likewise not systematic. Although for certain journals (e.g., the Journal of Medical Entomology) the table of contents of each issue were inspected, many other articles were discovered via regular reading or social media. Articles were selected that either appeared in print in final form in 2020, or that became available online that year, following peer-review and acceptance (although the final citation may be published in 2021). The highlighted articles fit within themes of ticks and tick-borne diseases, from surveillance to understanding environmental determinants of range expansions; biology and genetics of invasive Aedes species; mosquito host choice and feeding behavior; effects of vector diversity on pathogen transmission; novel vector control approaches; and studies highlighting impacts of human-mediated environmental change on vector behavior and vectorial capacity. considerably exceed the currently known distributions of ticks. This may be due to a lack of systematic, long-term surveillance efforts in certain locations, or reflect that the ranges of the most important vectors will continue to expand in the future (Eisen and Paddock 2020) . This highlights the need for tick and tick-borne pathogen surveillance, not just in established Lyme foci, but also in areas that are on the invasive edge of one or more important vector species. The spatial and temporal changes in human Lyme borreliosis cases in the United States between 2000 and 2017 were investigated using a statistical model to understand environmental drivers of the spread of this disease (Bisanzio et al. 2020) . Counties reporting the first case of Lyme Disease were found to be related to several factors: 1) established Ixodes scapularis Say (Ixodida: Ixodidae) populations, 2) a higher proportion of forest coverage and proportion of residents living near the urban-wildland interface, and 3) neighboring counties that had already reported cases. This study also highlighted the South and East North Central regions of the United States as having high rates of active spread or geographic expansion. In addition to range expansion, transmission patterns have undergone alterations in established, high Lyme Disease incidence areas. To understand how nymphal I. scapularis populations changed in Maine between 1990 and 2013 , Elias et al. (2021 used a long-term passive tick surveillance dataset to disentangle the effects of changes in deer density and climate. Deer density had a strongly nonlinear effect on tick abundance, with an increase in nymphs occurring up to a density of 5 deer/km 2 , whereas warmer winters and more rapid degree-day accumulation were associated with greater tick abundance, but only occurred in areas with at least 2 deer/km 2 , highlighting the need to consider climatic drivers in concert with environmental factors related to deer populations. In addition to the primary causative agent of Lyme, Borrelia burgdorferi s.s., Ixodes spp. also transmit a variety of other pathogens, including the emerging pathogen that causes hard tick relapsing fever, Borrelia miyamotoi. This pathogen can be vertically transmitted from female ticks to their offspring, but much of the transmission ecology remains unclear, including the relative importance of vertical and horizontal transmission. In Ixodes pacificus (Cooley and Kohls) populations in California, the infection prevalence was found to increase with each life stage from 0.11% in larvae to 8.74% in adults, pointing to the importance of horizontal transmission in this region (Sambado et al. 2020) . The potential importance of vertical transmission from a public health perspective was noted by Han et al. (2021) , who investigated the prevalence of infection with B. miyamotoi and the density of infected ticks in Wisconsin and Massachusetts. Despite a lower prevalence of infection, the greater density of larvae suggests this life stage may pose a significant risk of exposure to this pathogen, depending on their contact rate with humans, potentially affecting the seasonal risk profile of this emerging pathogen. Another tick species that appears to be undergoing a rapid range expansion in recent years is the Gulf Coast tick, Amblyomma maculatum (Koch), whose distribution was originally confined to the Gulf Coast and Southeastern states. Established populations have been reported in a wider range of states in recent years (e.g., Phillips et al. 2020) . In Delaware, this tick was first reported in 2013, but a recent study there found established populations in three counties, with decreasing densities along a north-south gradient, and 21% infection prevalence with Rickettsia parkeri (Maestas et al. 2020 ). The population genetic structure of newly established populations of this species in Virginia indicated that different populations were genetically distinct, with little evidence of gene flow among them, pointing to multiple distinct introductions leading to establishment (Benham et al. 2021 ). It could be that the northern edge of the humid subtropical zone in the United States is expanding and leading to favorable conditions for Gulf Coast tick establishment further north than previously recognized. Lone star ticks, Amblyoma americanum (L.), likewise appear to be expanding their range northwards. For instance, in recent years they have displaced I. scapularis as the most commonly encountered tick in New Jersey. These ticks were found to have a high prevalence of Rickettsia amblyommatis infection, a bacterium of unknown pathogenicity which may be implicated in milder cases of spotted fever group rickettsial disease (Egizi et al. 2020a ). The body of knowledge related to the invasive Asian longhorned tick, Haemaphysalis longicornis (Neuman), also has continued to expand. A comprehensive laboratory study evaluated the ability of this species to acquire and transmit the agent of Rocky Mountain Spotted Fever, Rickettsia rickettsii. Larvae and nymphs were shown to become infected after feeding on infected guinea pigs, carry the infection transstadially across life stages, and transmit to naïve hosts, suggesting further assessment under field conditions will be necessary to evaluate to what extent this species may become involved in R. rickettsii transmission cycles (Stanley et al. 2020) . Insight into the possible origins of H. longicornis populations in the United States came from a study investigating mitochondrial cox1 sequences of populations from nine states in the Unites States and several countries that potentially might have served as sources. The haplotypes found present in the United States all clustered with other known parthenogenetic phenotypes, and a northeast Asian source appeared most likely (Egizi et al. 2020b ). One of the most important arbovirus vectors globally, Aedes aegypti, L. (Diptera: Culicidae) is thought to have originated in continental Africa. A new study by Soghigian et al. (2020) explored the evolutionary relationship of populations of Aedes aegypti formosus (continental populations with a broader host range) and Aedes aegypti aegypti (populations from outside Africa) to aegypti group species found in islands of the Indian Ocean. This analysis suggests that an ancestral Stegomyia lineage diversified in the Indian Ocean islands around 16 million years ago, and that this group was basal and gave rise to Ae. aegypti s.s. in continental Africa (Soghigian et al. 2020) . Further insights into the evolution of anthropophagic behavior in Ae. aegypti came from a study that investigated the host choice of this species for human versus other animal odor and tied this to environmental factors at the 27 sites in sub-Saharan Africa from which populations were assessed. The majority of the variation in host preference was related to the intensity of the dry season and, to a lesser extent, human population density, pointing to a reliance on water storage by humans in strongly seasonal environments as a potential selective force behind anthropophily in this species (Rose et al. 2020 ). An important question for invasive mosquitoes is whether and how their vector competence and other traits related to vectorial capacity change due to genetic changes during the invasion process. This topic was explored for Aedes albopictus (Skuse) populations from various continents, including their center of origin. Six distinct lineages were identified and tested for dissemination and transmission efficiency of the chikungunya virus. Two of these lineages, that were dominant in La Reunion and the Mediterranean region, showed greater levels of vector competence, highlighting that in newly invaded areas, the public health outcomes may be affected by the source of origin (Vega-Rua et al. 2020) . Gains also continued to be made in our understanding of the environmental and land use factors driving receptivity for invasion. In a study making use of data from 338 trap sites in New York State, the authors found that areas associated with low-and medium-level development, as well as low proportions of deciduous cover, were more likely to have increased numbers of Ae. albopictus, whereas the effects of precipitation on Ae. albopictus abundance was positive at lower levels, but then found to switch to a negative relationship above a threshold of ca. 70 mm during the preceding 28 d, perhaps due to flushing of habitats (Kache et al. 2020 ). Studies of mosquito blood-host preferences and feeding rates and plant-sugar feeding are critically important to understanding both vectorial capacity (VC) and, potentially, for the development and use of control measures that exploit mosquito feeding habits. How the proportion of hosts fed upon affects the vectorial capacity of Culiseta melanura (Coquillett) for Eastern equine encephalitis virus (EEEV) was investigated by West et al. (2020) . They found that spikes in equine cases of EEEV occurred in May and June in Florida, while their estimates of VC were highest from June to August (when abundance peaked). The peak in cases appeared to coincide with the increasing proportions of blood-fed and parous C. melanura and host use that included a mix of birds, reptiles, and mammals (West et al. 2020) . Whether and how these observed discrepancies were due to this being a zoonotic virus, with the possible involvement of additional bridge vectors, is worthy of further study. Nectar and bloodmeals serve different purposes for mosquitoes, trigger different metabolic pathways, and are shunted to different parts of the digestive tract, yet how mosquitoes tell these meals apart at a sensory level is not well understood, particularly given that glucose is a component of blood. A study using calcium-imaging identified four distinct neuron classes in the stylets of Ae. aegypti, which respond to specific components of blood and to glucose only when in the presence of other blood components. Further, these stylet neurons did not respond to nectar-specific sugars (Jove et al. 2020). Likewise, the sensory processing involved in nectar-source seeking remains understudied. This topic was addressed in a study using Ae. aegypti and other Aedes spp., and the orchid Platanthera obtusata, which is visited and pollinated by mosquitoes. P. obtusata was found to emit a blend of volatiles that included a pronounced level of nonanal, whereas other closely related orchids which do not elicit visitation by mosquitoes had odor profiles dominated by lilac aldehyde. Using calcium-imaging Lahondere et al. (2020) were able to show that both these volatiles activate antennal lobe glomeruli and that the ratio in which these occur appears to determine attractiveness and allow for discrimination between floral sources. Given the potential to harness mosquito's nectar-feeding habit for control or surveillance purposes, there is great value in improving our understanding of when, where, and how likely different species are to engage in this behavior. The rate at which Ae. albopictus feeds on sugar under field conditions in the northeastern U.S. was investigated. Approximately 42% of female Ae. albopictus were fructose positive, and positivity was greater when environmental conditions were dry and in locations where flowering plants were more abundant (Fikrig et al. 2020) . Sugar feeding under field conditions by Culex quinquefasciatus (Say) and Ae. aegypti was investigated in southern Texas (Olson et al. 2020 ). For Ae. aegypti, the sugar content of mosquitoes was greater from autumn collections than for those from the summer, suggesting a seasonal difference in sugar-feeding behavior. Overall approximately 43% of female Ae. aegypti were fructose positive, adding to the evidence that in certain environments this species does frequently feed on sugar. A challenge in medical entomology relates to accurately assessing the demography of natural vector populations. A literature review of survival estimates for field populations cautioned that different methodologies for estimating mosquito survival from field-collected populations can lead to different biases, and sometimes large differences in survival estimates (Matthews et al. 2020) . Another enduring question is whether and how infection with pathogens changes mosquito behavior and physiology. One such aspect, how infection changes mosquito behavior when exposed to repellents, was addressed using a systematic review and meta-analysis. Across all studies, the authors found a 62% reduction in repellency attributable to pathogen infection of the vector, but this effect was strongly dependent on several factors, including mosquito age and the pathogen studied. Notably, Plasmodium and dengue did not show an effect on repellency, whereas infection with Edhazardia aedis, Zika virus, or Sindbis virus did (Lajeunesse et al. 2020 ). The main theoretical underpinnings of medical entomology, from the development and refinement of Ross-Macdonald models to concepts such as vectorial capacity, have their basis in single vector and host systems. Interest is growing in understanding how the transmission ecology of multivector and multihost systems differ, and what these repercussions mean for surveillance and control. Differences among members of species complexes are also being studied. In Chicago, which experiences persistently high West Nile virus transmission, the host selection and genetic makeup of Culex pipiens (L.) complex mosquitoes was investigated during July and August in 2012. The vast majority (99%) of bloodmeals in this study came from avian hosts, with both northern cardinals and American robins being bitten more frequently than their abundance would suggest. There was a modest amount of introgression between Cx. pipiens f. pipiens and f. molestus, as well as between Cx. pipiens f. pipiens and Cx. quinquefasciatus (Say), but no evidence was found that hybridizations led to differences in feeding patterns (Kothera et al. 2020) . Differences in responses to host volatiles were shown between Cx. quinquefasciatus and Cx. pipiens molestus in laboratory behavioral assays comparing attraction to headspace volatiles of magpies, chickens, and pigeons, with or without CO 2 . Although the addition of CO 2 to the headspace volatiles led to an increase in responsiveness by Cx. quinquefasciatus, this was not the case for Cx. pipiens molestus, suggesting these species have developed different host-seeking strategies (Spanoudis et al. 2020) . The role of Culex species also was investigated in Andalusia, Spain, where both West Nile virus (WNV) and avian malaria are transmitted by Cx. pipiens, Culex perexiguus Theobald, and Culex modestus Ficalbi. The authors developed a multispecies R 0 model and used field-collected data to determine species-specific contributions to the transmission that suggested Cx. perexiguus was the main driver of WNV transmission in this region, whereas the R 0 of Plasmodium was higher when Cx. pipiens was present in the mosquito community (Ferraguti et al. 2020) . A reanalysis of mosquito and malaria surveys from Kilifi, Kenya, assessed various components of vector diversity and how this affected malaria transmission. There was a positive relationship between anopheline species richness and malaria prevalence in humans, and community composition influenced malaria prevalence as well, where a high ratio of Anopheles arabiensis Patton to Anopheles gambiae Giles led to a decrease in prevalence (Hoi et al. 2020 ). The dependency of vector control on approaches that rely on a handful of insecticides has become a liability due to the evolution of insecticide resistance and other constraints. Integrated approaches that use a wider variety of methods, based on a sound understanding of local ecology and guided by monitoring and evaluation have been promoted as a more sustainable way forward (Wilson et al. 2020) . It is also clear that additional, novel methods of control will be needed. A brief overview of some of exciting developments from this past year is described here. The potential to target the nectar-feeding behavior of mosquitoes for control has received a lot of attention in recent years. Another approach where this behavior could play a role is in microbial forms of control, where nectar-feeding could potentially be a means to transfer bacteria to mosquito populations. Asaia spp. have been investigated for their use in paratransgenesis, the genetic modification of this bacterium to impede the competence of mosquitoes for specific pathogens. A recent study isolated Asaia spp. from plants and mosquitoes in Senegal, and demonstrated that mosquitoes could inoculate flowers with Asaia, and subsequently these plants could transmit the bacterium to mosquitoes through nectarfeeding (Bassene et al. 2020) . The use of Wolbachia continues to show promise as a dengue control mechanism. In a field trial performed in Kuala Lumpur, Malaysia, the potential to use the wAlbB strain of Wolbachia for dengue control was investigated. Ae. aegypti carrying this strain were released at 6 sites with endemic dengue, and the persistence of Wolbachia and human dengue incidence were monitored (Nazni et al. 2019) . The prevalence of Wolbachia in mosquitoes rose quickly, and remained stable in some sites, while others required additional mosquito releases. Dengue incidence was estimated to decrease by approximately 40% following the releases (Nazni et al. 2019) . A newly detected vertically-transmitted symbiont, Microspodia MB, was found to be present in An. arabiensis populations in Kenya, and laboratory studies indicate infection with this microsporidian limits the development of Plasmodium falciparum, suggesting it could be investigated as an additional malaria control measure (Herren et al. 2020) . The development of transgenic mosquito lines carrying both an effector molecule to prevent the development of specific pathogens inside the mosquito, and a coupled gene drive to allow this transgene to spread through populations even if the effector gene harbors a fitness cost has long been a goal in this field. With developments in Cas9 and guide RNA technology, major steps toward this goal are being taken. A gene drive strain was developed for An. gambiae which targets the cardinal gene and results in a red-eye phenotype. In small cage trials introduction of gene-drive males led to the full establishment within 6-10 generations, and, importantly, there were no fitness costs found (Carballar-Lejarazu et al. 2020) . Other transgenic approaches include the development of an autosomal sex ratio distorter. This was tested in a 4-month experiment in large indoor cages with overlapping generations to measure fitness costs associated with the transgene (in addition to the effects on sex ratio), which were present. Model simulations based on this suggested the transgene would be lost from populations within several years (Pollegiono et al. 2020 ). A number of studies have been investigating the circadian or seasonal rhythms of mosquitoes and how these may be affected by humanmediated changes in environmental light intensity. Additional work on the molecular basis of circadian rhythms is likewise advancing. For instance, a study of the regulation of circadian rhythms in diurnal and nocturnal mosquito species [Ae. aegypti and Anopheles coluzzii (Coetzee & Wilkerson)] found differences in daytime light avoidance behavior, and PERIOD proteins cycled in opposite phases between two species of mosquitoes, suggesting these circadian clock protein phases may underlie differences in nocturnal and diurnal behaviors (Baik et al. 2020) . Human changes to light patterns and disruptions of normal circadian rhythms due to 'artificial light at night' (ALAN) affect a wide range of animals. For Ae. aegypti, it appears ALAN may increase their tendency to bite humans at times when they normally would not, at least in laboratory cages (Rund et al. 2020) . Simulated artificial light at night was found to considerably reduce the induction of diapause in Ae. albopictus. In urban field sites, although populations showed differences in diapause induction in early September, later on, all populations reached high levels of diapause, suggesting that the effect of artificial light may be minimized due to vegetation or other factors (Westby and Medley 2020) . Other natural occurrences, such as inland flooding, are likely to occur more frequently with climate change and with changes in land use. Effects of such events on arboviral disease risk are not well understood. In a statistical analysis of Ross River virus (RRV) cases in New South Wales, Australia, it was found that Spring and Summer flooding in certain climate zones led to an increase in the probability of a summer RRV outbreak (Tall and Gatton 2020) . Effects of increasing temperatures have been studied extensively for malaria and dengue, but much less so for arboviruses transmitted in temperate settings. For WNV, a study that used trait-based models predicted peak transmission around summer temperatures of 24-25°C, which matched county-level data on West Nile disease incidence (Shocket et al. 2020) . This suggested that with increasing temperatures, climate effects on transmission will be strongly location-dependent and either positive or negative. The effects of temperature on adult mosquito survival differed in interesting ways from tropical vectors that have been assessed previously, with a linear decline in survival as a function of increasing temperature (Shocket et al. 2020) . In Coastal California, the use of spatio-temporal machine learning algorithms identified inhibitory, promoting, and transitional temperature bounds, and found that parts of the state where summer temperatures passed the transitionary zone more frequently saw the greatest expansion of West Nile positive mosquito pools over a ten-year period (Skaff et al. 2020 ). This could potentially help further pinpoint areas where climate change could lead to future increases in WNV transmission. Similar temperaturedependent models of vectorial capacity also may be used to understand variation in urban settings, where a mosaic of green space and impervious surface can lead to fine-scale temperature-driven variation in vector-borne disease risk. This was illustrated in Athens, GA, for Ae. albopictus, where urban areas with patches of trees led to the highest predicted vectorial capacity, a result of buffering in such areas against more extreme day-and night-time temperatures, resulting in temperatures that stay more closely to the thermal optimum of this species (Wimberley et al. 2020). The field of vector-borne diseases is continually changing as a result of many of the factors that have been highlighted in this review, including range expansions or shifts of vector species, changes in land use and host distributions due to human activity and development, and climate change and other human-mediated environmental changes. These shifts offer tremendous potential as natural experiments; for instance, by perturbing transmission cycles, as evidenced by many of the papers discussed here. It also highlights the need for multidisciplinary, collaborative approaches, increased funding, and continuing research on vector behavior, life history, genetics, and ecology, in order to improve our understanding of transmission cycles of established and emerging vector-borne diseases, the consequences of range expansions of invasive vectors, and to improve our surveillance capacity and develop sustainable, integrated vector control measures. Circadian regulation of light-evoked attraction and avoidance behaviors in daytime-versus nighttime-biting mosquitoes Role of plants in the transmission of Asaia sp., which potentially inhibit the Plasmodium sporogenic cycle in Anopheles mosquitoes Comparative population genetics of Amblyomma maculatum and Amblyomma americanum in the mid-Atlantic United States Current and future spatiotemporal patterns of lyme disease reporting in the northeastern United States What is the impact of lockdowns on dengue? Curr Next-generation gene drive for population modification of the malaria vector, Anopheles gambiae Infecting Lone Star Ticks (Amblyomma americanum) (Acari: Ixodidae) in Monmouth County, New Jersey First glimpse into the origin and spread of the Asian longhorned tick, Haemaphysalis longicornis, in the United States Tick and tickborne pathogen surveillance as a public health tool in the United States A generalized additive model correlating blacklegged ticks with white-tailed deer density, temperature, and humidity in maine The role of different Culex mosquito species in the transmission of West Nile virus and avian malaria parasites in Mediterranean areas Sugar feeding patterns of New York Aedes albopictus mosquitoes are affected by saturation deficit, flowers, and host seeking Seasonality of acarological risk of exposure to Borrelia miyamotoi from questing life stages of Ixodes scapularis collected from Wisconsin and A microsporidian impairs Plasmodium falciparum transmission in Anopheles arabiensis mosquitoes Deconstructing the impact of malaria vector diversity on disease risk Sensory discrimination of blood and floral nectar by Aedes aegypti mosquitoes Environmental Determinants of Aedes albopictus abundance at a northern limit of its range in the united States Bloodmeal, host selection, and genetic admixture analyses of Culex pipiens complex (Diptera: Culicidae) mosquitoes in Chicago, IL The olfactory basis of orchid pollination by mosquitoes Infected mosquitoes have altered behavior to repellents: a systematic review and meta-analysis Surveillance for Amblyomma maculatum (Acari: Ixodidae) and Rickettsia parkeri (Rickettsiales: Rickettsiaceae) in the state of Delaware, and their Public health implications An overview of malarial Anopheles mosquito survival estimates in relation to methodology Establishment of Wolbachia strain wAlbB in Malaysian populations of Aedes aegypti for dengue control Sugar feeding patterns for Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) mosquitoes in South Texas Documentation of the expansion of the Gulf Coast tick (Amblyomma maculatum) and Rickettsia parkeri: first report in Illinois Detecting the population dynamics of an autosomal sex ratio distorter transgene in malaria vector mosquitoes Climate and urbanization drive mosquito preference for humans Artificial light at night increases Aedes aegypti mosquito biting behavior with implications for arboviral disease transmission Mixed transmission modes promote persistence of an emerging tick-borne pathogen Transmission of West Nile and five other temperate mosquito-borne viruses peaks at temperatures between 23°C and 26°C Thermal thresholds heighten sensitivity of West Nile virus transmission to changing temperatures in coastal California Genetic evidence for the origin of Aedes aegypti, the yellow fever mosquito, in the southwestern Indian Ocean Behavioural response of the house mosquitoes Culex quinquefasciatus and Culex pipiens molestus to avian odours and its reliance on carbon dioxide The ability of the invasive Asian longhorned tick Haemaphysalis longicornis (Acari: Ixodidae) to acquire and transmit Rickettsia rickettsii (Rickettsiales: Rickettsiaceae), the agent of rocky mountain spotted fever, under laboratory conditions Flooding and arboviral disease: predicting ross river virus disease outbreaks across inland regions of south-eastern Australia Predicted impact of COVID-19 on neglected tropical disease programs and the opportunity for innovation Vector competence of Aedes albopictus populations for chikungunya virus is shaped by their demographic history Vectorial capacity of Culiseta melanura (Diptera: Culicidae) changes seasonally and is related to epizootic transmission of Eastern Equine Encephalitis virus in Central Florida Cold nights, city lights: artificial light at night reduces photoperiodically induced diapause in urban and rural populations of Aedes albopictus (Diptera: Culicidae) The importance of vector control for the control and elimination of vector-borne diseases Land cover affects microclimate and temperature suitability for arbovirus transmission in an urban landscape I am grateful to Drs. Dana Nayduch and Michael Reiskind, and other members of the Medical, Urban and Veterinary Entomology (MUVE) section, for the opportunity to present the 2020 Highlights in Medical Entomology at the annual meeting of the Entomological Society of America, Holly Tuten for edits and discussion, and Dr. Bill Reisen and two anonymous reviewers for their suggestions and comments. Chris Stone is a medical entomologist at the Illinois Natural History Survey at the University of Illinois at Urbana-Champaign. His interests include the behavior, ecology, life history, and control of vectors.