- Retired professor, medical entomology, Colorado State Universityedit
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Ae. albopictus occurrences 1960-201
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This datafile contains a comprehensive list of occurrences of Ae. aegypti and Ae. albopictus from 1960-2014
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Aedes aegypti and Ae. albopictus are the main vectors transmitting dengue and chikungunya viruses. Despite being pathogens of global public health importance, knowledge of their vectors’ global distribution remains patchy and sparse. A... more
Aedes aegypti and Ae. albopictus are the main vectors transmitting dengue and chikungunya viruses. Despite being pathogens of global public health importance, knowledge of their vectors’ global distribution remains patchy and sparse. A global geographic database of known occurrences of Ae. aegypti and Ae. albopictus between 1960 and 2014 was compiled. Herein we present the database, which comprises occurrence data linked to point or polygon locations, derived from peer-reviewed literature and unpublished studies including national entomological surveys and expert networks. We describe all data collection processes, as well as geo-positioning methods, database management and quality-control procedures. This is the first comprehensive global database of Ae. aegypti and Ae. albopictus occurrence, consisting of 19,930 and 22,137 geo-positioned occurrence records respectively. Both datasets can be used for a variety of mapping and spatial analyses of the vectors and, by inference, the di...
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A laboratory study of selected factors important to competitive displacement showed that the yellow-fever mosquito, Aedes (Stegomyia) aegypti (L.) (Diptera: Culicidae), was uniformly more vigorous than a competitor species, A. (S.)... more
A laboratory study of selected factors important to competitive displacement showed that the yellow-fever mosquito, Aedes (Stegomyia) aegypti (L.) (Diptera: Culicidae), was uniformly more vigorous than a competitor species, A. (S.) albopictus (Skuse). After a single flooding period, egg hatch of A. aegypti was 95% vs. 60–85% in A. albopictus. If eggs were continuously Hooded for 5 days, 50% of A. aegypti eggs hatched in 2 hours, while nearly 2 days were needed for 50% hatch of A. albopictus eggs. Egg mortality was greater in A. albopictus in all cases. Species population ratios of 10:90, 50:50, and 90:10, plus control groups of each species were reared at densities of 0.1 larva per milliliter and 0.8 larva per milliliter. A. aegypti development time was consistently more rapid than that of A. albopictus, particularly at low density. At high density, larval development time was longer in both species, the relative increase being greater in A. aegypti than in A. albopictus. Density and species ratio effects were essentially the same for males as for females. Competition between A. aegypti and A. albopictus larvae in various stages was clearly shown. Larval mortality was consistently higher when the species were reared together than in single species controls. If A. albopictus and A. aegypti were reared together at high density, larval development time of both was proportional to percent A. aegypti. The increased larval development period was shown to be caused by a heat-stable distillable metabolite of A. aegypti larvae.
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In order to understand adquately the dynamics of vector-borne disease, one must understand how and why vector populations change over time. We describe a long-term, cooperative study of seasonal fluctuation in populations of the Aedes... more
In order to understand adquately the dynamics of vector-borne disease, one must understand how and why vector populations change over time. We describe a long-term, cooperative study of seasonal fluctuation in populations of the Aedes aegypti mosquito in Puerto Rico. During each month of the first 3 years of the project, A. aegypti was found breeding in all five communities studied. Mosquito density was positively correlated with rainfall, the relationship being more marked in the dry, south-coastal part of the island. Discarded tires and animal watering pans were the two most common larval breeding sites. In general, houses in Puerto Rico harbor more potential A. aegypti breeding sites than those in other tropical locations, probably because Puerto Rico is relatively more affluent.
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The National Ecological Observatory Network (NEON) intends to monitor mosquito populations across its broad geographical range of sites because of their prevalence in food webs, sensitivity to abiotic factors, and relevance for human... more
The National Ecological Observatory Network (NEON) intends to monitor mosquito populations across its broad geographical range of sites because of their prevalence in food webs, sensitivity to abiotic factors, and relevance for human health. We describe the design of mosquito population sampling in the context of NEON's long‐term continental scale monitoring program, emphasizing the sampling design schedule, priorities, and collection methods. Freely available NEON data and associated field and laboratory samples, will increase our understanding of how mosquito abundance, demography, diversity, and phenology are responding to land use and climate change.
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Aedes albopictus, the Asian "tiger mosquito," was found in Houston, Texas, in 1985. Aedes albopictus is primarily a forest edge inhabiting species that has readily adapted to the container habitats produced by humans. Although... more
Aedes albopictus, the Asian "tiger mosquito," was found in Houston, Texas, in 1985. Aedes albopictus is primarily a forest edge inhabiting species that has readily adapted to the container habitats produced by humans. Although not yet incriminated in the spread of any disease in the Americas, it has been repeatedly implicated in epidemic dengue and dengue hemorrhagic fever transmission in Asia. It is a competent laboratory vector of La Crosse, yellow fever and other viruses, and can transovarially transmit at least 15 viruses. In 1986, Ae. albopictus was found in many other Texas counties, and in Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Louisiana, Mississippi, Missouri, Ohio, and Tennessee. In 1987, infestations were discovered in Delaware, Kentucky, Maryland, and North Carolina. Aedes albopictus and other exotic species were intercepted in shipments of used tires entering the United States from Asia. All such tires must now be free of mosquitoes before ente...
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Extensive surveys were conducted in 1987 in Baytown, TX; Lafayette, Shreveport and Baton Rouge, LA; Memphis, TN; Kansas City, MO; Evansville, IN; and Jacksonville, FL. The program objective was to determine the intensity of Aedes... more
Extensive surveys were conducted in 1987 in Baytown, TX; Lafayette, Shreveport and Baton Rouge, LA; Memphis, TN; Kansas City, MO; Evansville, IN; and Jacksonville, FL. The program objective was to determine the intensity of Aedes albopictus infestations, to evaluate the degree to which Ae. albopictus had spread into residential areas, to document habitat selection and to obtain background information for possible suppression or eradication projects. This report describes the survey methods and presents a preliminary analysis of the data. Larvae, pupae and adult mosquitoes were collected from container habitats in a randomized selection of urban premises as well as at and around sites known to be at high risk for introduction of Ae. albopictus. Adult or larval mosquitoes were collected from 24.4% of 5,728 premises inspected, and there were an average of 3.27 positive containers per positive premise. Several known disease vectors, especially Culex pipiens (s.l.), were frequently found...
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Parasites and pathogens are increasingly recognized as significant drivers of ecological and evolutionary change in natural ecosystems. Concurrently, transmission of infectious agents among human, livestock, and wildlife populations... more
Parasites and pathogens are increasingly recognized as significant drivers of ecological and evolutionary change in natural ecosystems. Concurrently, transmission of infectious agents among human, livestock, and wildlife populations represents a growing threat to veterinary and human health. In light of these trends and the scarcity of long‐term time series data on infection rates among vectors and reservoirs, the National Ecological Observatory Network (NEON) will collect measurements and samples of a suite of tick‐, mosquito‐, and rodent‐borne parasites through a continental‐scale surveillance program. Here, we describe the sampling designs for these efforts, highlighting sampling priorities, field and analytical methods, and the data as well as archived samples to be made available to the research community. Insights generated by this sampling will advance current understanding of and ability to predict changes in infection and disease dynamics in novel, interdisciplinary, and co...
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This Article was mistakenly not made Open Access when originally published; this has now been amended, and information about the Creative Commons Attribution 4.0 International License has been added into the ‘Additional information’... more
This Article was mistakenly not made Open Access when originally published; this has now been amended, and information about the Creative Commons Attribution 4.0 International License has been added into the ‘Additional information’ section.
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Aedes (Stegomyia) aegypti (L.) and Aedes (Stegomyia) albopictus (Skuse) transmit arboviruses that are increasing threats to human health in the Americas, particularly dengue, chikungunya, and Zika viruses. Epidemics of the associated... more
Aedes (Stegomyia) aegypti (L.) and Aedes (Stegomyia) albopictus (Skuse) transmit arboviruses that are increasing threats to human health in the Americas, particularly dengue, chikungunya, and Zika viruses. Epidemics of the associated arboviral diseases have been limited to South and Central America, Mexico, and the Caribbean in the Western Hemisphere, with only minor localized outbreaks in the United States. Nevertheless, accurate and up-to-date information for the geographical ranges of Ae. aegypti and Ae. albopictus in the United States is urgently needed to guide surveillance and enhance control capacity for these mosquitoes. We compiled county records for presence of Ae. aegypti and Ae. albopictus in the United States from 1995-2016, presented here in map format. Records were derived from the Centers for Disease Control and Prevention ArboNET database, VectorMap, the published literature, and a survey of mosquito control agencies, university researchers, and state and local heal...
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Page 1. November 1966] FORCE : REACTIONS OF GREEN DOCK BEETLE 1125 were most suprising. Downey (1962) found that local populations of the lycaenid butterfly Plebejus tear hides (Boisduval) used only 1 species ...
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Research Interests: Geography, Biology, Medicine, Dengue Virus, Humans, and 6 moreAnimals, Dengue, Scientific Data, Chikungunya Virus, Aedes, and Insect Vectors
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Dengue and chikungunya are increasing global public health concerns due to their rapid geographical spread and increasing disease burden. Knowledge of the contemporary distribution of their shared vectors, Aedes aegypti and Ae. albopictus... more
Dengue and chikungunya are increasing global public health concerns due to their rapid geographical spread and increasing disease burden. Knowledge of the contemporary distribution of their shared vectors, Aedes aegypti and Ae. albopictus remains incomplete and is complicated by an ongoing range expansion fuelled by increased global trade and travel. Mapping the global distribution of these vectors and the geographical determinants of their ranges is essential for public health planning. Here we compile the largest contemporary database for both species and pair it with relevant environmental variables predicting their global distribution. We show Aedes distributions to be the widest ever recorded; now extensive in all continents, including North America and Europe. These maps will help define the spatial limits of current autochthonous transmission of dengue and chikungunya viruses. It is only with this kind of rigorous entomological baseline that we can hope to project future heal...
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Adult female density, parity status, and wing length were determined weekly for a population of Coquillettidia perturbans in an area enzootic for eastern equine encephalitis virus in central Ohio. Samples were collected in CO2-baited CDC... more
Adult female density, parity status, and wing length were determined weekly for a population of Coquillettidia perturbans in an area enzootic for eastern equine encephalitis virus in central Ohio. Samples were collected in CO2-baited CDC miniature light traps from the first week in June through the 2nd week of September 1992. Population density indicated a single emergence peak during the 2nd week in July. However, parity rates showed 2 peaks, occurring in the first week of August (70.9% parous) and the 2nd week of September (55.3% parous), which suggested that there was a relatively small 2nd generation. Average wing length declined significantly over the season. The decline in size was negatively correlated with average air temperature occurring at least 6 wk before the time of emergence. Despite the seasonal decline in wing length, the low coefficient of variation for the average wing length (5.5) indicated relatively little variation in size. Comparison of parous and nulliparous...
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Potosi (POT) virus, a recently characterized Bunyamwera serogroup virus, was discovered when it was isolated from Aedes albopictus collected at a waste-tire site in Potosi, Washington County, Missouri, during 1989. During the following... more
Potosi (POT) virus, a recently characterized Bunyamwera serogroup virus, was discovered when it was isolated from Aedes albopictus collected at a waste-tire site in Potosi, Washington County, Missouri, during 1989. During the following year, POT virus was not isolated from 39,048 mosquitoes, including 17,519 Ae. albopictus, collected in Washington County. In 1991, mosquito collections from South Carolina, Ohio, and Michigan yielded 8 strains of POT virus: 6 from Coquillettidia perturbans and one each from Culex restuans and Psorophora columbiae. Additional collections of Ae. albopictus from several states during 1990-93 failed to yield further isolates of POT virus. In 1994, POT virus was isolated from Ae. albopictus and Anopheles punctipennis in North Carolina and from Ae. albopictus in Illinois. These represent the first virus isolations of any type for Ae. albopictus in those states. Thus far, POT virus has been isolated from 5 mosquito species in different genera in 6 states. Th...
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The Asian "tiger mosquito" Aedes albopictus has become established in the southern United States. The Centers for Disease Control has taken a number of steps to respond to the problem. Appropriate state and international... more
The Asian "tiger mosquito" Aedes albopictus has become established in the southern United States. The Centers for Disease Control has taken a number of steps to respond to the problem. Appropriate state and international agencies have been informed, and data on biology, public health importance and identification have been prepared and distributed to state and local agencies. Studies on insecticide susceptibility and vector competence are in progress, as is surveillance throughout the southeast, in cooperation with state and local agencies. The introduction of Ae. albopictus presents a major challenge to the mosquito control community.
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Since its initial discovery in the continental USA in 1985, the Asian tiger mosquito, Aedes albopictus, has spread rapidly throughout the eastern part of the country. Infestations of Ae. albopictus now have been reported to the Centers... more
Since its initial discovery in the continental USA in 1985, the Asian tiger mosquito, Aedes albopictus, has spread rapidly throughout the eastern part of the country. Infestations of Ae. albopictus now have been reported to the Centers for Disease Control and Prevention from 919 counties in 26 states in the continental USA. This species is believed to be established in 911 counties in 25 states. Single individuals or small numbers of Ae. albopictus have been intercepted and destroyed in 3 additional states (California, New Mexico, and Washington). Five states (Florida, Georgia, North Carolina, South Carolina, and Tennessee) have reported infestations in all of their counties. The current reported distribution of Ae. albopictus was compared to ecoregions of the U.S. Environmental Protection Agency's Level III ecoregion map. Several areas are identified as probable candidates for extension of this species based on ecological characteristics of the landscape. In other areas, popula...
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An epidemic of St. Louis encephalitis (SLE) occurred in Jefferson County, Arkansas during July-August 1991. At least 26 human cases were involved, with 25 cases in the town of Pine Bluff. Twelve isolates of SLE virus were obtained from... more
An epidemic of St. Louis encephalitis (SLE) occurred in Jefferson County, Arkansas during July-August 1991. At least 26 human cases were involved, with 25 cases in the town of Pine Bluff. Twelve isolates of SLE virus were obtained from mosquitoes collected in Pine Bluff between August 13 and 24: 11 from pools of Culex pipiens quinquefasciatus, resulting in a minimum infection rate of 1.6 per 1,000 (n = 6,768) for this subspecies, and one isolate from a pool of 22 mosquitoes identified as Cx. (Culex) spp. Three of the SLE-positive pools, two from Cx. p. quinquefasciatus and one from Cx. (Cux.) spp., also yielded isolates of Flanders virus. Larval surveys resulted in the collection of seven species in four genera from 28 larva-positive habitats and the identification of one significant site of Cx. p. quinquefasciatus production. Ecologic assessments conducted at 12 randomly selected residences resulted in the identification of 17 larva-positive habitats, for an average mosquito-positi...
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Several factors that were suspected of affecting the development of syncytia in cultured Aedes pseudoscutellaris cells inoculated with dengue viruses were studied. The results indicated that fresh media (less than 1 week old), low cell... more
Several factors that were suspected of affecting the development of syncytia in cultured Aedes pseudoscutellaris cells inoculated with dengue viruses were studied. The results indicated that fresh media (less than 1 week old), low cell density at inoculation (2.8 x 10(5) cells/cm2), and low cell passage level (less than 52 passages) favored the development of syncytia. All three types (1, 2, and 3) of dengue viruses tested could be isolated from human sera by Aedes pseudoscutellaris cell culture by using syncytial development as an indicator, but the isolation rate was lower than that obtained by using intrathoracically inoculated Aedes aegypti mosquitoes.
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The largest and most extensive documented dengue epidemic in Puerto Rico struck an estimated 355,000 Puerto Rican residents from July-December 1977. The mixed epidemic of dengue types 2 and 3 coincided with a Caribbean pandemic of dengue... more
The largest and most extensive documented dengue epidemic in Puerto Rico struck an estimated 355,000 Puerto Rican residents from July-December 1977. The mixed epidemic of dengue types 2 and 3 coincided with a Caribbean pandemic of dengue type 1, first introduced into the western hemisphere in early 1977 and into Puerto Rico in the fall of that year. Health officials assembled a team to assess the epidemic and mounted a campaign to end it. Attempts to monitor the incidence and spread of dengue were confounded by simultaneous co-circulation of influenza virus, underscoring problems in formulating public health strategies dependent on nonspecific clinical and epidemiologic case criteria, and the need for rapid and reliable diagnostic capabilities. Despite co-circulation of multiple dengue serotypes, a risk factor associated with severe and fatal dengue hemorrhagic fever (DHF) in Southeast Asia, hospital and death certificate surveillance disclosed no cases of DHF in Puerto Rico. The ep...
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The impact of ULV resmethrin on urban Culex mosquitoes was evaluated in 4 field trials by monitoring daily oviposition rate. A well-defined oscillation of effect, with a period corresponding to the duration of the gonotrophic cycle, was... more
The impact of ULV resmethrin on urban Culex mosquitoes was evaluated in 4 field trials by monitoring daily oviposition rate. A well-defined oscillation of effect, with a period corresponding to the duration of the gonotrophic cycle, was observed. We postulate that this oscillation arises from changes in susceptibility following blood feeding and/or behavioral factors. The data indicate that a single treatment with ULV may be inadequate for the effective control of vector mosquitoes.
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Aedes albopictus was first detected in Houston, Texas, in 1985. Since then it has spread to 17 states and 122 counties. This exotic species from Asia appears to have arrived in the U.S. in imported used tire casings. Public health... more
Aedes albopictus was first detected in Houston, Texas, in 1985. Since then it has spread to 17 states and 122 counties. This exotic species from Asia appears to have arrived in the U.S. in imported used tire casings. Public health concerns have been raised regarding the potential of this species to serve as a vector of arboviruses indigenous to the U.S., such as La Crosse encephalitis, and also for imported dengue. The Division of Vector-Borne Viral Diseases, Centers for Disease Control, has actively pursued a program to determine the distribution of Ae. albopictus in the U.S., monitor the spread of the species and implement procedures that would eliminate the risk of further importation of exotic mosquitoes in used tire casings. The latter goal was achieved in large measure in 1988 with a 98% reduction in imported used tires containing water. The ultimate consequences of establishment of Ae. albopictus in the U.S. is unknown; however, because of its biologic characteristics and bro...
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In the absence of a vaccine for use in humans against West Nile virus (WNV), mosquito control and personal protection against mosquito bites are the only measures available to prevent disease. Improved spatial targeting is desirable for... more
In the absence of a vaccine for use in humans against West Nile virus (WNV), mosquito control and personal protection against mosquito bites are the only measures available to prevent disease. Improved spatial targeting is desirable for costly mosquito and WNV surveillance and control schemes. We used a multivariate regression modeling approach to develop spatial models predicting high risk of exposure to WNV in western and eastern Colorado based on associations between Geographic Information System-derived environmental data and zip code of residence for 3,659 human WNV disease cases from 2002 to 2006. Models were robust, with user accuracies for correct classification of high risk areas of 67-80%. The importance of selecting a suitable model development area in an ecologically and climatically diverse environment was shown by models based on data from the eastern plains landscape performing poorly in the mountainous western part of Colorado and vice versa.
Research Interests: Geography, Risk, Medicine, Multivariate Analysis, Humans, and 15 moreModels, Temperature, Incidence, Model development, Mosquito Control, Colorado, Risk Factor, Time Factors, Multivariate Regression, Geographic Information System, Logistic Models, Spatial Model, The American, High risk, and Medical and Health Sciences
Arbovirus surveillance was conducted during an epizootic of western equine encephalitis (WEE) during 1987 and during a nonepizootic year, 1991, in the same area in northern Colorado. Mosquitoes were collected in Larimer County, CO, during... more
Arbovirus surveillance was conducted during an epizootic of western equine encephalitis (WEE) during 1987 and during a nonepizootic year, 1991, in the same area in northern Colorado. Mosquitoes were collected in Larimer County, CO, during weeks 33-37 (10 August to 7 September) in 1987 and during weeks 26-35 (24 June to 26 August) in 1991. In total, 13,099 mosquitoes in 694 pools collected during 1987 and 8,672 mosquitoes in 242 pools collected during 1991 were tested for virus. WEE virus was isolated in both years from Culex tarsalis Coquillett and from Cx. pipiens L. in 1987. Infection rates and population levels of Cx. tarsalis were not significantly different in the 2 yr during weeks 33, 34, and 35 (12-26 August). St. Louis encephalitis virus was isolated in 1987 from Cx. tarsalis. Other viruses isolated included Hart Park, Turlock, and Jerry Slough, a variety of Jamestown Canyon virus.
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Assessments of spatial risk of exposure to vector-borne pathogens that combine vector and human disease data are needed for areas encompassing large tracts of public land with low population bases. We addressed this need for West Nile... more
Assessments of spatial risk of exposure to vector-borne pathogens that combine vector and human disease data are needed for areas encompassing large tracts of public land with low population bases. We addressed this need for West Nile virus (WNV) disease in the northern Colorado Front Range by developing not only a spatial model for entomological risk of exposure to Culex tarsalis WNV vectors and an epidemiological risk map for WNV disease but also a novel risk-classification index combining data for these independently derived measures of entomological and epidemiological risk. Risk of vector exposure was high in the densely populated eastern plains portion of the Front Range but low in cooler montane areas to the west that are sparsely populated but used heavily for recreation in the summer. The entomological risk model performed well when applied to the western, mountainous part of Colorado and validated against epidemiologic data.
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Mosquitoes and wild birds were collected from three sites near locations in the New York City metropolitan area where single, West Nile (WN) virus-positive dead birds were found early in the 2000 transmission season. The mosquitoes were... more
Mosquitoes and wild birds were collected from three sites near locations in the New York City metropolitan area where single, West Nile (WN) virus-positive dead birds were found early in the 2000 transmission season. The mosquitoes were tested for the presence of infectious virus with a Vero cell culture assay and for WN viral RNA by using reverse transcriptase-polymerase chain reaction (RT-PCR) protocols. Serum samples from wild birds were tested for the presence of neutralizing antibodies against WN virus. Infectious WN virus and WN viral RNA were found in Culex species adult mosquitoes from each of the three sites, and a seropositive hatch-year house sparrow (Passer domesticus) was found in one of the three sites. Molecular techniques used to identify the species in the positive mosquito pools found that most of the pools contained a combination of Culex pipiens and Cx. restuans. The minimum infection rate in Culex species mosquitoes from the sites ranged from 0.2 to 6.0 per 1,00...
Research Interests: Aging, Cell Culture, Seasonality, New York City, Female, and 15 moreAnimals, Male, Songbirds, Culex, New York, House Sparrow, Passer domesticus, Culex pipiens, Neutralizing antibodies, The American, Insect Vectors, West Nile, reverse transcriptase polymerase chain reaction, Medical and Health Sciences, and Bird diseases
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Research Interests: Geography, Biology, Landscape, Medicine, Humans, and 15 moreAnimals, Regression Analysis, Population Density, Culex, Mosquito Control, West nile virus, Colorado, Ecosystem, Public health systems and services research, Larva, West Nile Fever, Seasons, Geographic Information System, Geographic Information Systems, and Insect Vectors
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In addition to their importance to human and animal health, vector-borne diseases are fascinating systems to study. The involvement of multiple species whose biologies and life cycles cover differing space and time scales makes it... more
In addition to their importance to human and animal health, vector-borne diseases are fascinating systems to study. The involvement of multiple species whose biologies and life cycles cover differing space and time scales makes it extremely difficult to predict epidemics. A single environmental factor may have opposite impacts on the system at different points in time. Patchiness at different geographical scales may have very different causes, so it is important to identify the proper scale for a particular study. New developments in remote sensing, GIS, and spatial analysis make it easier to tease out causes of observed patchiness. Interdisciplinary collaboration is essential for many of the projects we carry out, but this requires awareness of the differences between disciplines and the ability to effectively communicate with each other. It is only by forming multi-disciplinary groups to focus on specific vector-host-pathogen systems that we will be able to answer the most interesting (and pressing) problems in our field.