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Eastern equine encephalitis virus (EEEV; family Togaviridae, genus Alphavirus) is a mosquito-borne pathogen found in eastern North America that causes severe disease in humans and horses. The mosquito Culiseta melanura (Coquillett) (Diptera: Culicidae) is the primary enzootic vector of EEEV throughout eastern North America while several mosquito species belonging to diverse genera serve as bridge vectors. The ecology of EEEV differs between northern and southern foci, with respect to phenology of outbreaks, important vertebrate hosts, and bridge vector species. Active transmission is limited to roughly half of the year in northern foci (New York, New Hampshire, Massachusetts, Connecticut), while year-round transmission occurs in the southeastern region (particularly Florida). Multiple phylogenetic analyses indicate that EEEV strains circulating in northern foci are likely transported from southern foci by migrating birds. Bird species that overwinter or migrate through Florida, are bitten by Cs. melanura in late spring, and arrive at northern breeding grounds in May are the most likely candidates to disperse EEEV northward. Available data indicate that common yellowthroat and green heron satisfy these criteria and could serve as virus dispersers. Understanding the factors that drive the phenology of Cs. melanura reproduction in the south and the timing of avian migration from southern foci could provide insight into how confluence of these biological phenomena shapes outbreaks of EEE throughout its range. This information could be used to develop models predicting the likelihood of outbreaks in a given year, allowing vector control districts to more efficiently marshal resources necessary to protect their stakeholders.

The mosquito Culiseta melanura (Coquillett) is the primary enzootic vector of eastern equine encephalitis virus (EEEV), a zoonotic Alphavirus endemic to eastern North America. In its northern range, Cs. melanura is considered a strict avian biter, transmitting EEEV among susceptible birds in a cycle of enzootic amplification. In its southern range, however, Cs. melanura is more general in host use, feeding heavily upon birds but also reptiles and mammals. The goal of this study was to better understand how host use of Cs. melanura changes throughout the year in Florida, where year-round EEEV transmission is observed. Mosquitoes were sampled in 2018 from nine sites across three central Florida counties. In total, 213 Cs. melanura bloodmeals were identified by PCR consisting of 39 species of birds, reptiles, and mammals. Avian bloodmeals were prominent throughout the year (range = 30–85%), and songbirds were a large portion of identified bloodmeals (37.1%). Reptiles surpassed birds only in spring (April–June), and brown anole (Anolis sagrei Duméril and Bibron, 1837 [Reptilia: Dactyloidae]) was the most commonly detected single host species (22.1% overall). Mammalian bloodmeals were mainly observed in summer, with humans being the most fed on mammal (12.7% overall). This study reveals that in southern foci of EEEV transmission, Cs. melanura host use varies throughout the year with reptiles providing the majority of blood meals in spring (51.3%), and birds are fed on more than other host groups during all other seasons (50.6–70.1%). In addition, feeding on mammals increases during summer months, which may implicate Cs. melanura in epizootic transmission in Florida.

In the western United States, this virus may have been mediated via migrating infected birds from southern South America, where it reemerged most recently in 2002., We summarize and analyze historical and current data regarding the reemergence of St. Louis encephalitis virus (SLEV; genus Flavivirus) in the Americas. Historically, SLEV caused encephalitis outbreaks in the United States; however, it was not considered a public health concern in the rest of the Americas. After the introduction of West Nile virus in 1999, activity of SLEV decreased considerably in the United States. During 2014–2015, SLEV caused a human outbreak in Arizona and caused isolated human cases in California in 2016 and 2017. Phylogenetic analyses indicate that the emerging SLEV in the western United States is related to the epidemic strains isolated during a human encephalitis outbreak in Córdoba, Argentina, in 2005. Ecoepidemiologic studies suggest that the emergence of SLEV in Argentina was caused by the introduction of a more pathogenic strain and increasing populations of the eared dove (amplifying host).

Richard Floyd Darsie, Jr. (1915-2014) is the 2015 American Mosquito Control Association Memorial Lecture Honoree. He was one of the greatest mosquito taxonomists of the 20th century and died peacefully on April 10, 2014, in Grove City, PA, at the age of 99 after a professional career that spanned eight decades. Dick's broad areas of interest and training made him a versatile scientist, teacher, and researcher. His intense interest in adult and immature mosquito morphology and taxonomy, as well as mosquito distribution and bionomics, started early in his career at two early academic postings: Franklin and Marshall College (1949-54) and the University of Delaware (1954-62). Dick would take his mosquito interests with him to postings and research projects around the world: Nepal, the Philippines, Atlanta, El Salvador, Guatemala, Fort Collins, South Carolina, Argentina, and Florida. His travels and studies would make him an international expert on mosquito taxonomy. Dick's legacy lives on in the hundreds of students from across the globe who learned mosquito identification skills from this world-renowned mosquito taxonomist. All will proudly profess that, "I learned mosquito identification from Dr. Darsie." And that is all that is needed to prove one's credentials in the field, learning the art from the best there is.

West Nile virus (WNV) was first detected in North America in New York City during the late summer of 1999 and was first detected in Florida in 2001. Although WNV has been responsible for widespread and extensive epidemics in human populations and epizootics in domestic animals and wildlife throughout North America, comparable epidemics have never materialized in Florida. Here, we review some of the reasons why WNV has yet to cause an extensive outbreak in Florida. The primary vector of mosquito-borne encephalitis virus in Florida is Culex nigripalpus Theobald. Rainfall, drought, and temperature are the primary factors that regulate annual populations of this species. Cx. nigripalpus is a competent vector of WNV, St. Louis encephalitis virus, and eastern equine encephalitis virus in Florida, and populations of this species can support focal amplification and transmission of these arboviruses. We propose that a combination of environmental factors influencing Cx. nigripalpus oviposition, blood-feeding behavior, and vector competence have limited WNV transmission in Florida to relatively small focal outbreaks and kept the state free of a major epidemic. Florida must remain vigilant to the danger from WNV, because a change in these environmental factors could easily result in a substantial WNV epidemic rivaling those seen elsewhere in the United States.

Few studies have assessed arthropods associated with carrion in salt marsh environments. Arthropods attracted to animal carcasses in a salt marsh environment were surveyed in southeastern Florida during four seasons from September 2009 to July 2010. A total of 2,324 arthropod specimens were collected from carcasses (coyote, opossum, raccoon, bobcat, and otter) and 4 orders, 23 families, 28 genera, and 24 species were identified. Specimens were most frequently encountered from the order Diptera (85% of total), and Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae) and Musca domestica (L.) (Diptera: Muscidae) represented 50% of specimens collected. We observed seasonal variation in abundance of dipterans. The information presented here may be useful for future studies identifying arthropods having wildlife forensic entomology significance within subtropical Florida salt marsh habitats.

Aims In the HORIZONS trial, in-hospital treatment with bivalirudin reduced bleeding and mortality in primary percutaneous coronary intervention (PCI) compared with heparin and routine glycoprotein IIb/IIIa inhibitors (GPI). It is unknown whether this advantage of bivalirudin is observed in comparison with heparins only with GPI used as bailout. Methods and results In the EUROMAX study, 2198 patients with ST-segment elevation myocardial infarction (STEMI) were randomized during transport for primary PCI to bivalirudin or to heparins with optional GPI. Primary and principal outcome was the composites of death or non-CABG-related major bleeding at 30 days. This pre-specified analysis compared patients receiving bivalirudin ( n = 1089) with those receiving heparins with routine upstream GPI ( n = 649) and those receiving heparins only with GPI use restricted to bailout ( n = 460). The primary outcome death and major bleeding occurred in 5.1% with bivalirudin, 7.6% with heparin plus routine GPI (HR 0.67 and 95% CI 0.46–0.97, P = 0.034), and 9.8% with heparins plus bailout GPI (HR 0.52 and 95% CI 0.35–0.75, P = 0.006). Following adjustment by logistic regression, bivalirudin was still associated with significantly lower rates of the primary outcome (odds ratio 0.53, 95% CI 0.33–0.87) and major bleeding (odds ratio 0.44, 95% CI 0.24–0.82) compared with heparins alone with bailout GPI. Rates of stent thrombosis were higher with bivalirudin (1.6 vs. 0.6 vs. 0.4%, P = 0.09 and 0.09). Conclusion Bivalirudin, started during transport for primary PCI, reduces major bleeding compared with both patients treated with heparin only plus bailout GPI and patients treated with heparin and routine GPI, but increased stent thrombosis.

The epidemiology of vector-borne pathogens is determined by mechanisms and interactions at different scales of biological organization, from individual-level cellular processes to community interactions between species and with the environment. Most research, however, focuses on one scale or level with little integration between scales or levels within scales. Understanding the interactions between levels and how they influence our perception of vector-borne pathogens is critical. Here two examples of biological scales (pathogen transmission and mosquito mortality) are presented to illustrate some of the issues of scale and to explore how processes on different levels may interact to influence mosquito-borne pathogen transmission cycles. Individual variation in survival, vector competence, and other traits affect population abundance, transmission potential, and community structure. Community structure affects interactions between individuals such as competition and predation, and thus influences the individual-level dynamics and transmission potential. Modeling is a valuable tool to assess interactions between scales and how processes at different levels can affect transmission dynamics. We expand an existing model to illustrate the types of studies needed, showing that individual-level variation in viral dose acquired or needed for infection can influence the number of infectious vectors. It is critical that interactions within and among biological scales and levels of biological organization are understood for greater understanding of pathogen transmission with the ultimate goal of improving control of vector-borne pathogens.

Changes in the time to first bite (TFB) and the bloodfeeding behavior of adult female Aedes aegypti (L.) mosquitoes following dissemination of Sindbis virus (SINV) were observed after exposure to repellents with the active ingredients (AI) DEET, picaridin, 2-undecanone (2-U), and oil of lemon eucalyptus. Dissemination of SINV significantly decreased (P0.0001) the TFB of DEET (15%) and picaridin (15%) by 46% and 37%, respectively. Significant (P0.0001) changes in activation, probing, and engorgement times were observed in SINV infected mosquitoes after exposure to the four repellents compared to uninfected mosquitoes. Taken together, a decrease in TFB and time to complete the four bloodfeeding stages will lessen the prey-status, and enhance both the chances of mosquito survival and arbovirus transmission.

To determine whether a Sindbis virus (family Togaviridae, genus Alphavirus, SINV) infection in Aedes aegypti (L.) (Diptera: Culicidae) affected its response to the repellent DEET, we orally exposed Ae. aegypti to an artificial bloodmeal containing SINV or diluent and then allowed to feed on a 10% sucrose suspension containing 3% DEET. When tested seven or more days after the initial bloodmeal, although none of the diluent-exposed mosquitoes fed on the DEET-sucrose suspension, at least 60% of the SINV-exposed mosquitoes fed on the suspension. When legs from the SINV-exposed mosquitoes were tested to determine dissemination status, 89% of those that fed on the DEET-sucrose suspension contained virus. In contrast, only 34% of the nonfeeders had a disseminated infection. When offered a choice between sucrose with or without DEET, a significantly higher percentage of the SINV-exposed mosquitoes than the control mosquitoes fed on the sucrose containing 3% DEET. Together, these results indicate that mosquitoes with a disseminated SINV infection may be less responsive to DEET than uninfected mosquitoes. Therefore, repellent use may be less effective in deterring infected mosquitoes from biting than previously believed.

Understanding the transmission patterns of West Nile and St. Louis encephalitis viruses (family Flaviviridae, genus Flavivirus, WNV and SLEV) could result in an increased ability to predict transmission risk to humans. To examine transmission patterns between vector and host, we trapped mosquitoes in three Florida counties from June to November 2005 by using chicken-baited lard can mosquito traps. These traps were used to monitor for presence of WNV and SLEV in mosquitoes and subsequent transmission of these viruses to chickens. In total, 166,615 female mosquitoes were sorted into 4,009 pools based on species and bloodfed status, and they were tested for presence of WNV and SLEV. Sera from 209 chickens were tested for WNV and SLEV antibodies. We detected eight WNV-positive Culex nigripalpus Theobald mosquito pools; SLEV was not detected in any pools. Six positive pools were collected in August and September from Duval County, one pool in September from Manatee County, and one pool in November from Indian River County. Of the eight chickens potentially exposed to WNV, antibodies were detected in only one chicken, indicating a low rate of transmission relative to the observed mosquito infection rates. Low virus transmission rates relative to infection rates would suggest that using sentinel chicken seroconversion data as a means of arbovirus surveillance may underestimate the prevalence of WNV in the mosquito population. However, using mosquito infection rates may overestimate the risk of arboviral transmission. A variety of factors might account for the observed low level of transmission including a lack of viral dissemination in mosquito vectors.

Overdosing of parenteral antithrombotic therapies can increase the risk of bleeding. Cangrelor is a potent intravenous platelet P2Y12 receptor antagonist with rapid onset and offset of action. In patients undergoing percutaneous coronary interventions (PCI), compared with control, cangrelor (30 µg/kg bolus, followed immediately by a 4 µg/kg per minute infusion for 2–4 h or until the conclusion of the index PCI, whichever was longer) reduces periprocedural thrombotic complications without an increase in major bleeding complications, although minor bleeding is increased. The impact of cangrelor overdosing on bleeding is unknown and represented the aim of this analysis. Patients with cangrelor overdosing were identified among safety population patients enrolled in the CHAMPION program (n = 25,107). Overdose was defined as administration of an excess >20 % of the bolus dose (30 μg/kg) and/or infusion rate (4 μg/kg per min). Bleeding complications were assessed. Among the safety analysis population in the CHAMPION program, 12,565 patients received cangrelor. A total of 36 overdosed cangrelor patients (0.29 %) were identified in this pooled analysis (20 with both bolus and infusion, 5 with bolus only, and 11 with infusion only). In the majority of patients, the dose did not exceed 2.5 times the recommended dose. Bleeding events were balanced between treatment arms and were consistent with those in the overall CHAMPION program. Only one overdosed patient experienced a serious bleed. There was no correlation between bleeding and magnitude of cangrelor overdose. In a large clinical trial program of patients undergoing PCI, cangrelor overdosing was rare and not associated with an increase in bleeding complications, an observation that may be attributed to its very short-half life and rapid offset of action.

Mark-release-recapture experiments were conducted in 2001 and 2002 to determine whether Ochlerotatus taeniorhynchus, black salt marsh mosquitoes, were dispersing from uninhabited islands in the Key Deer National Wildlife Refuge to inhabited islands within Monroe County, Florida. An estimated 1,658,000 mosquitoes were marked during 2001, and an estimated 300,000 mosquitoes were marked during 2002. Recapture rates were 0.0061% and 0.0117%, respectively. Oc. taeniorhynchus disperse from uninhabited islands to other uninhabited islands and also to inhabited islands, namely, Big Pine Key and No Name Key.

Sampling indoor resting African malaria vectors is traditionally done by hand catches with oral or mechanical aspirators and pyrethrum spray catches (PSCs). In this study, we designed and briefly evaluated an inexpensive but practical alternative by using a cloth resting box or wicker resting basket and a ceiling net. Evaluations were performed in greenhouse and field situations in rural Kenya by comparing capture rates of Anopheles gambiae s.l. and Anopheles funestus (Giles) in these traps to hand collections and PSCs. A resting box and a ceiling net when used together collected more mosquitoes than a single collector using a hand-held aspirator but only one-third the number collected by PSCs. At sites where PSCs are impractical, a resting box and ceiling net can be effectively used as an alternative to hand catches in malaria surveillance.

We present a method for the ensemble seasonal prediction of human St. Louis encephalitis (SLE) incidence and SLE virus transmission in Florida. We combine empirical relationships between modeled land surface wetness and the incidence of human clinical cases of SLE and modeled land surface wetness and the occurrence of SLE virus transmission throughout south Florida with a previously developed method for generating ensemble, seasonal hydrologic forecasts. Retrospective seasonal forecasts of human SLE incidence are made for Indian River County, Florida, and forecast skill is demonstrated for 2–4 months. A sample seasonal forecast of human SLE incidence is presented. This study establishes the skill of a potential component of an operational SLE forecast system in south Florida, one that provides information well in advance of transmission and may enable early interventions that reduce transmission. Future development of this method and operational application of these forecasts are discussed. The methodology also will be applied to West Nile virus monitoring and forecasting.

The crested auklet, Aethia cristatella, emits a class of aldehydes shown to be potent invertebrate repellents when used by heteropterans against their predators. Our aim was to determine the efficacy of these aldehydes against mosquitoes in the laboratory. Synthetic analogues of the auklet odorant were strongly repellent to mosquitoes in controlled laboratory trials. Furthermore, the efficacy was similar to previous reports for commercial mosquito repellents. These results, in combination with a previously published study, show that constituents of the aldehyde odorant are broad spectrum in efficacy against ectoparasitic arthropods of birds. Our report is the first empirical evidence for an endogenous mosquito repellent in birds.

We show that the spatial-temporal variability of human West Nile (WN) cases and the transmission of West Nile virus (WNV) to sentinel chickens are associated with the spatial-temporal variability of drought and wetting in southern Florida. Land surface wetness conditions at 52 sites in 31 counties in southern Florida for 2001-2003 were simulated and compared with the occurrence of human WN cases and the transmission of WNV to sentinel chickens within these counties. Both WNV transmission to sentinel chickens and the occurrence of human WN cases were associated with drought 2-6 mo prior and land surface wetting 0.5-1.5 mo prior. These dynamics are similar to the amplification and transmission patterns found in southern Florida for the closely related St. Louis encephalitis virus. Drought brings avian hosts and vector mosquitoes into close contact and facilitates the epizootic cycling and amplification of the arboviruses within these populations. Southern Florida has not recorded a severe, widespread drought since the introduction of WNV into the state in 2001. Our results indicate that widespread drought in the spring followed by wetting during summer greatly increase the probability of a WNV epidemic in southern Florida.

Disease transmission forecasts can help minimize human and domestic animal health risks by indicating where disease control and prevention efforts should be focused. For disease systems in which weather-related variables affect pathogen proliferation, dispersal, or transmission, the potential for disease forecasting exists. We present a seasonal forecast of St. Louis encephalitis virus transmission in Indian River County, Florida. We derive an empirical relationship between modeled land surface wetness and levels of SLEV transmission in humans. We then use these data to forecast SLEV transmission with a seasonal lead. Forecast skill is demonstrated, and a real-time seasonal forecast of epidemic SLEV transmission is presented. This study demonstrates how weather and climate forecast skill verification analyses may be applied to test the predictability of an empirical disease forecast model.

We analyzed the prevalence of hemagglutination inhibition (HI) antibodies to St. Louis encephalitis (SLE) virus in wild birds during the 1990 SLE epidemic in Indian River County. The initial presence of SLE HI antibody was associated significantly with modeled drought 15 wk prior, wetting conditions 1 wk prior, and the emergence of the Florida SLE virus vector, Culex nigripalpus, 5 wk prior. Our findings indicated that three factors conspired to create the 1990 epidemic: (1) a large population of susceptible wild birds; (2) severe springtime drought, which facilitated amplification of the SLE virus among the Cx. nigripalpus and a portion of the wild bird population; and (3) continued rainfall and wetting of the land surface in the summer and early fall, which sustained a large, host-seeking Cx. nigripalpus population. The continued biting and reproductive activity of Cx. nigripalpus maintained epizootic transmission throughout the summer and early fall in Indian River County. The high level of SLE virus amplification resulted in spillover transmission to humans. We hypothesize that without the continued reproductive activity of the vector mosquito, brought about by excessive summer and fall wetness, the unprecedented SLE virus amplification and consequent transmission to humans would not have been realized in 1990.

West Nile virus (WNv) has spread through much of the eastern United States following its introduction in 1999, and arrived in Florida in 2001. Prior to its arrival, we anticipated that its transmission cycle was likely to be similar to that of St. Louis encephalitis virus (SLEv). However, high levels of avian mortality have been reported for WNv in the northeastern United States, and it was unknown how this would impact the transmission dynamics of WNv. Simulation models were used to compare the two viruses by considering the impact of bird mortality on the transmission dynamics of arboviruses in south Florida. Transmission models without disease-induced mortality (SLEv) were compared with models including disease-induced mortality (WNv). Disease-induced mortality depressed transmission, eliminating epizootics in two of 14 simulations that were epizootic without the additional mortality. In both models, the most important factor in the likelihood of epizootics was mosquito population size; the mosquito mortality rate was also important. The additional avian mortality altered the factors most important in the size and timing of epizootics, although it did not always directly affect the outcome of the simulations. In some cases, low-level transmission occurred prior to the epizootic peak. When disease-induced avian mortality was included in the simulations, appreciable numbers of dead birds occurred prior to high levels of infection in mosquitoes. This has implications for the use of dead birds as a surveillance tool monitoring the spread and transmission of WNv.

▪ Abstract St. Louis encephalitis virus was first identified as the cause of human disease in North America after a large urban epidemic in St. Louis, Missouri, during the summer of 1933. Since then, numerous outbreaks of St. Louis encephalitis have occurred throughout the continent. In south Florida, a 1990 epidemic lasted from August 1990 through January 1991 and resulted in 226 clinical cases and 11 deaths in 28 counties. This epidemic severely disrupted normal activities throughout the southern half of the state for 5 months and adversely impacted tourism in the affected region. The accurate forecasting of mosquito-borne arboviral epidemics will help minimize their impact on urban and rural population centers. Epidemic predictability would help focus control efforts and public education about epidemic risks, transmision patterns, and elements of personal protection that reduce the probability of arboviral infection. Research associated with arboviral outbreaks has provided an understanding of the strengths and weaknesses associated with epidemic prediction. The purpose of this paper is to review lessons from past arboviral epidemics and determine how these observations might aid our ability to predict and respond to future outbreaks.

Four general frequencies of human St. Louis encephalitis (SLE) virus (epidemic, focal, sporadic, and no transmission) occurred in Florida between 1990 and 1999. An epidemic with 226 clinical cases and 11 deaths was reported from 28 Florida counties between July 1990 and January 1991. During the autumn of 1993, a focal outbreak was reported from Lee (5 cases) and Collier (3) Counties in southwest Florida. During the autumn of 1997, sporadic transmission to nine humans was reported from five Florida counties (Brevard [1 case], Polk [3], Charlotte [1], Lee [2], and Palm Beach [2]). Human infection with SLE virus depends on a number of variables that drive virus transmission. These include vector, virus, and avian host abundance, and meteorological events, especially rainfall. We monitored the abundance and serological status of wild avian amplification hosts, virus isolations from Culex nigripalpus Theobald females, and SLE virus transmission to sentinel chickens during 1990, 1993, and 1997. The epidemic of 1990 was characterized by conditions that produced an unusual abundance of vector mosquitoes and avian amplification hosts early in the year. We propose that epidemics may result when a specific combination of biotic and abiotic conditions favor SLE virus minimum field infection rates that approach 1:1,000 in Cx. nigripalpus vectors.

Blood and serum from 3,915 wild and domestic birds (2,590 resident, 139 migrant, and 1,186 captive), representing 56 species collected in central Florida from 1989 through 1997, were analyzed for evidence of St. Louis encephalitis (SLE) virus transmission. All sera were tested for SLE hemagglutination inhibition (HI) antibody. Selected sera and bloods were tested for SLE neutralizing (NT) antibody and virus. The reproductive success of resident birds was highest from 1990-1992 and lowest from 1994-1997. Transmission of SLE to resident birds, especially mourning doves (Zenaida macroura), peaked during the summer of 1990, a year during which a widespread SLE epidemic was recorded in central Florida. The SLE antibody-positive resident birds 1st appeared during September of the epidemic year. Some SLE, HI antibody-positive resident birds were captured throughout 1991, but only 5% were yearlings, compared with 36% in 1990. By 1993, wild resident birds expressing HI and NT antibodies to SLE had nearly disappeared. None of the migrant birds tested were SLE-positive. Sentinel chickens maintained in Indian River County during the epidemic year seroconverted to SLE starting in early July with peak seroconversion rates in August, September, and October. High (or = 50%) SLE seroconversion rates in sentinel chickens preceded those in wild birds by 10 wk and preceded peak human SLE transmission by at least 8 wk. Major SLE epidemics in south Florida depend on abundant wild bird populations, especially during the amplification phase of the transmission cycle. We propose that hard winter freezes along the temperature-subtropical climatic zone interface in central Florida, at approximately 27 degrees 30' North Latitude, opens foraging and nesting habitats for ground-feeding birds, resulting in high reproductive success and an abundance of seronegative individuals that rapidly amplify the SLE later in the year.

The pupa of Culex salinarius is redescribed with updated chaetotaxal nomenclature and a full illustration. The pupal chaetotaxy of Cx. salinarius and the similar species Culex nigripalpus is compared.

Background In patients with ST-segment elevation myocardial infarction (STEMI) triaged to primary percutaneous coronary intervention (PCI), anticoagulation often is initiated in the ambulance during transfer to a PCI site. In this prehospital setting, bivalirudin has not been compared with standard-of-care anticoagulation. In addition, it has not been tested in conjunction with the newer P2Y 12 inhibitors prasugrel or ticagrelor. Design EUROMAX is a randomized, international, prospective, open-label ambulance trial comparing bivalirudin with standard-of-care anticoagulation with or without glycoprotein IIb/IIIa inhibitors in 2200 patients with STEMI and intended for primary percutaneous coronary intervention (PCI), presenting either via ambulance or to centers where PCI is not performed. Patients will receive either bivalirudin given as a 0.75 mg/kg bolus followed immediately by a 1.75-mg/kg per hour infusion for ≥30 minutes prior to primary PCI and continued for ≥4 hours after the end of the procedure at the reduced dose of 0.25 mg/kg per hour, or heparins at guideline-recommended doses, with or without routine or bailout glycoprotein IIb/IIIa inhibitor treatment according to local practice. The primary end point is the composite incidence of death or non–coronary-artery-bypass-graft related protocol major bleeding at 30 days by intention to treat. Conclusion The EUROMAX trial will test whether bivalirudin started in the ambulance and continued for 4 hours after primary PCI improves clinical outcomes compared with guideline-recommended standard-of-care heparin-based regimens, and will also provide information on the combination of bivalirudin with prasugrel or ticagrelor.

The Report “Emerging vectors in the Culex pipiens complex” by D. M. Fonseca et al. (5 Mar., p. [1535][1]) advances sweeping extrapolations concerning mosquito blood-feeding behavior and West Nile virus (WNV) transmission. These findings led Fonseca to conclude ([1][2]) that a European

From January 1990 through March 1991, 189 armadillos (Dasypus novemcinctus) were collected from Brevard and Glades Counties in southern Florida (USA). The sera were analyzed for hemagglutination-inhibition (HAI) antibodies against St. Louis encephalitis (SLE) and eastern equine encephalomyelitis (EEE) viruses. None of the armadillos had detectable HAI antibody to EEE virus, but 59 (31%) had antibodies against SLE virus. Sera from 31 of the HAI-positive armadillos contained significant levels of neutralizing (NT) antibody to SLE virus. Armadillos captured during the 1990 SLE human epidemic in south Florida had a greater prevalence of HAI and NT antibody to SLE virus than did animals captured before the start of the epidemic. This is evidence that armadillos were fed on by mosquitoes infected with SLE virus. We propose that armadillos may be involved in the SLE amplification and transmission cycles in Florida.

Seventy-four species of mosquitoes are reported in Florida, some, including Aedes taeniorhynchus (Wiedemann), A. sollicitans (Walker), and A. vexans (Meigen), in such numbers periodically as to present a major nuisance. Yet only one, Culex nigripalpus Theobald, is involved in the epidemic transmission of St. Louis encephalitis (SLE) virus. Why? What is unusual about the biology and behavior of this species that makes it such an important vector of the virus? The purpose of this article is to review the natural history of C. nigripalpus and, in so doing, identify the physiological and biological factors that make it the most dangerous mosquito in Florida.

The classic approach to vector control where large tracts of land are treated with an insecticide has many shortcomings. These include high cost, chemical resistance of target species to many of the widely used insecticides, a lack of public acceptance, and the detrimental effect of sprays on nontarget species. Removal trapping, the use of visual, auditory, and olfactory attractants to lure target species into small areas where they are killed, has recently received well-deserved attention as a possible alternative to the broadcast application of chemicals for vector control. We briefly review the histories of four successful removal trapping programs; Hippelates eye gnats in the United States, tsetse flies in Africa, Stomoxys calcitrans flies in Australia, and tabanids in the United States. We then review the future prospects of removal trapping and evaluate its potential as a viable method for vector control.

Mosquito-borne viruses (arboviruses) have the capacity to cause widespread epidemics in humans, as well as epizootics in domestic animals and wildlife. These epidemics and epizootics can be extremely costly and disruptive. Because most mosquito-borne arboviruses can cause encephalitis and encephalomyelitis in host vertebrates, healthcare issues associated with human infections can result in significant economic impact on local economies and health care providers (Villari et al., 1995). Likewise, the loss of domestic animals to encephalitis infection can produce significant adverse financial impacts on local agricultural industries (Wilson et al., 1986; Anon, 2003). Recent mosquito-borne epidemics caused by West Nile virus (family Flaviviridae, genus Flavivirus, WNV) in North America and Chikungunya virus (family Togaviridae, genus Alphavirus, CHIKV) in the islands of the Indian Ocean are examples of how mosquito-borne viruses can severely impact local, regional, and national economies. All mosquito-borne virus disease transmission cycles are driven by four factors: 1) the annual cycle of the pathogen (the specific arbovirus), 2) the annual cycle of the mosquito vector, 3) the annual cycle of the amplification, reservoir, and secondary vertebrate hosts that are infected with a specific viral pathogen, and 4) the environmental factors that drive each biological cycle independently and at times cause these three cycles to synchronize in ways that produce epidemics and epizootics (Day, 2001). Because three biological cycles, pathogen, vector and host, inform the transmission dynamics of a specific arboviral disease, surveillance protocols have been developed to monitor each of these cycles in order to estimate the local risk of arboviral transmission for a specific region. For example, it is possible to use sentinel animals to detect and measure the spatial and temporal distributions of specific arboviruses. Sentinel chickens, pheasants, quail, pigeons, and hamsters have been successfully used to monitor the transmission of St. Louis encephalitis virus (family Flaviviridae, genus Flavivirus, SLEV), WNV, eastern equine encephalitis virus (family Togaviridae, genus Alphavirus, EEEV), and Venezuelan equine encephalitis virus (family Togaviridae, genus Alphavirus, VEEV). Likewise, competent mosquito vectors can be identified for each mosquito-borne arbovirus transmission cycle. Once regional mosquito vectors have been identified, their populations can be tracked and important factors such as abundance, population age structure, and infection status can be monitored and used to

Eastern equine encephalomyelitis virus (EEEV) has been a low-frequency, but serious human and veterinary health problem. Increased frequency of this mosquito-borne virus is anticipated as wetlands are maintained and re-established. Control of EEEV has depended on mosquito abatement in response to increasing frequency of EEEV in the environment. A coupled reverse transcription/polymerase chain reaction assay was designed to rapidly, sensitively, and specifically detect EEEV RNA. The assay successfully detected the viral RNA in a single-blind study of a set of field samples composed of either pooled mosquitoes or bird tissue. These results suggest that it would be practical to use this assay for deciding when and where to implement mosquito abatement.

Fecundity of mosquitoes can vary with many factors and can have a strong effect on population growth. This study reports the effects of body size, blood meal size, and age on the reproductive output of nulliparous Culex quinquefasciatus, a vector of arboviruses and other pathogens. Mated adult female mosquitoes from a colony were reared under standard conditions and fed on chickens at different ages post-eclosion. Blood meal size and wing length were recorded, as well as the number of eggs in the first-cycle egg raft. Each of these factors had a significant influence on fecundity considered in a simple regression context. Multiple regression analysis revealed a significant interaction effect between age and body size on fecundity. Up to 13 days of age, fecundity was positively correlated with body size, but in mosquitoes older than 13 days, this relationship was not significantly different from zero. These results are discussed in terms of the known physiology of this and other species.

Mosquito-borne arboviral epidemics tend to strike without warning. The driving force for these epidemics is a combination of biotic (vector, amplification host, and virus) and abiotic (meteorological conditions, especially rainfall and temperature) factors. Abiotic factors that facilitate the synchronization and interaction of vector and amplification host populations favor epidemic amplification and transmission. In Florida, epidemics of St. Louis encephalitis (SLE) virus (family Flaviviridae, genus Flavivirus, SLEV) have been preceded by major freezes one or two winters before the onset of human cases. Here, we analyze the relationship between severe winter freezes and epidemic SLEV transmission in peninsular Florida and show that there is a significant relationship between the transmission of SLEV and these severe freezes. We propose that by killing cold-sensitive understory vegetation in the mid-peninsular region of Florida, freezes enhance the reproductive success of ground-feeding avian amplification hosts, especially mourning doves and common grackles. In conjunction with other appropriate environmental signals, increased avian reproductive success may enhance SLEV and West Nile (WN) virus amplification and result in SLE and WN epidemics during years when all of the biological cycles are properly synchronized. The knowledge that winter freezes in Florida may enhance the amplification and epidemic transmission of SLE and WN viruses facilitates arboviral tracking and prediction of human risk of SLE and WN infection during the transmission season.

The objective of this study was to examine the extrinsic risk factors of West Nile virus (WNV) clinical disease in Florida horses as established from confirmed and negative horses tested within the state from 2001 to 2003. An Arboviral Case Information Form (ACF) was submitted by a referring veterinarian at the time of testing to the Florida Department of Agriculture and Consumer Services on every horse suspected of a viral encephalitis in Florida. A follow-up survey that focused on arbovirus prevention and farm ecology was created and mailed to the owner of each tested horse. Data from the follow-up survey indicated peak WNV prevalence in the late summer months in Florida. Quarter horses were the most commonly affected breed. The WNV vaccine was highly protective and natural water on the property also had a protective association. Factors that increased the risk of WNV to horses were the use of fans and a stable construction of solid wood or cement. Some risk indicators were dead birds on the property and other ill animals on the property. Data from this retrospective study have helped identify factors associated with WNV transmission in equines in Florida. Horses that have not been vaccinated and show clinical signs of arboviral infection from June to November should be tested for WNV. Horses that have been vaccinated and show clinical signs should be tested when the vaccination was administered within 1 month or greater than 6 months prior to the onset of clinical symptoms associated with WN infection.

The optical, fluorescent, and photoconductive properties of solution-processable functionalized pentacene and anthradithiophene (ADT) derivatives are presented. Considerable fluorescence quantum yields of ~ 70-75% and ~ 40 — 50% were observed in several ADT derivatives in toluene solutions and in thin films, respectively. Using conventional wide-field fluorescence microscopy, ADT derivatives were successfully imaged in the polymethylmethacrylate (PMMA) matrix on a single molecule level, at 532 nm at room temperature. All films exhibited fast charge carrier photogeneration upon 100 fs 400 nm excitation and power-law decay dynamics of the transient photocurrent over many orders of magnitude in time. In solution-deposited ADT thin films, effective charge carrier mobilities calculated from the space-charge-limited currents reached ~ 0.1 cm 2 /Vs. In the same films, bulk photoconductive gains of up to 130 were observed at 532 nm continuous wave (cw) excitation with light intensity of 0.58 mW/cm 2 at the applied electric field of 4 x 10 4 V/cm. Effects of metal-organic interfaces on the dark current and transient and cw photocurrent are also discussed.

Sentinel chicken flocks monitored arboviral transmission at 12 sites in Sarasota County, Fla., from 1978 through 1988. During this time, 3,452 serum samples were analyzed for hemagglutination inhibition antibody to St. Louis encephalitis virus (SLE) and eastern equine encephalomyelitis virus (EEE). Overall, 91 chickens seroconverted to SLE and three to EEE. The intensity of SLE transmission showed considerable year-to-year variation. Chickens from south-county flocks were more likely to seroconvert to SLE virus than chickens maintained at the north-county sites. The SLE seroconversion rate for midcounty sentinels was intermediate between north- and south-county sites. Chickens were caged in four habitat types: oak hammocks, slash pine-saw palmetto areas, pastures, and urban-residential areas. There was no significant difference in SLE seroconversion rates between habitats.

The accurate forecasting and tracking of arboviral transmission is becoming increasingly critical for the early recognition and management of arboviral epidemics. Meteorological factors, especially rainfall and temperature, drive arboviral epidemics, but monitoring rainfall and temperature alone is not predictive of increased levels of vector-borne disease transmission. In Florida, model simulations of water table depth (WTD) provide a measure of drought, and they have been shown to provide an accurate forecast of arboviral transmission. Here, we tracked WTD in two peninsular Florida regions where focal West Nile virus (family Flaviviridae, genus Flavivirus, WNV) transmission was reported during 2004 and 2005. We compared the resulting WTD profiles with historical WTD simulations for Indian River County (IRC), FL, where two peninsular Florida St. Louis encephalitis virus epidemics had their epicenters in 1977 and 1990. In both of the regions where focal WNV transmission was reported during 2004 and 2005, the local WTD profiles approached the 1977 and 1990 IRC WTD profiles; however, differences in the local temporal sequence of hydrologic conditions were observed. These differences seem in part to explain why the focal WNV transmission during 2004 and 2005 failed to reach epidemic levels in peninsular Florida. These findings suggest that hydrologic monitoring, specifically WTD, may help determine the geographic extent, timing, and intensity of WNV transmission. We speculate that a more precise sequence of drought and wetting, including a secondary summer drying and wetting cycle, as occurred in IRC during 1977 and 1990, may provide the optimal hydrologic conditions for the expansion of an arbovirus outbreak from focal to epidemic. This study documents that monitoring hydrologic conditions, along with vector, avian amplification host, and virus population data, increases our ability to track and predict significant levels of arboviral transmission.

We present optical, fluorescent and photoconductive temperature dependent properties of novel high-performance solution-processable functionalized anthradithiophene and dicyanomethylenedihydrofuran derivatives. Changes in fluorescence lifetime, fluorescence quantum yield, and photoconductivity with temperature are discussed.

The mean adult body size of male and nonblood-fed female Culex nigripalpus Theobald mosquitoes showed a highly significant negative correlation with water temperature in the field. Large females were more successful in obtaining blood and developing eggs during an extended period of drought from March through September 1987. Small females emerged from field-collected pupae but were less successful in blood feeding and developing eggs in the field during the period of drought.

The pupa of Culex restuans is redescribed in detail with a chaetotaxal table and a full illustration. The chaetotaxy of the pupa of Cx. restuans is compared with that of Cx. nigripalpus, the primary vector of St. Louis encephalitis and West Nile virus in Florida.