USING ENVIRONMENTAL FACTORS TO PREDICT MOSQUITO-BORNE DISEASE TRANSMISSION IN FLORIDA

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: TERMINATED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 0212020
• Project No.: FLA-FME-004678
• Project Start Date: Oct 1, 2007
• Project End Date: Sep 30, 2013

Project Director
Day, J.

Recipient Organization
UNIVERSITY OF FLORIDA
G022 MCCARTY HALL
GAINESVILLE,FL 32611

Performing Department
FL Medical Entomology Lab, Vero Beach

Non Technical Summary
Arboviral surveillance is an important component of the Florida Medical Entomology Laboratory's (FMEL) legislatively mandated mission to conduct research to serve Florida residents and mosquito control programs. The economic impact of mosquito-borne diseases on Florida Counties cannot be easily measured. The confusion, expense, and panic associated with an epidemic that seemingly arises out of nowhere, similar to the 1999 New York City WN epidemic, is unacceptable. Epidemics of some mosquito-borne viruses are predicable. For example, the FMEL and Florida surveillance programs indicated the risk of epidemic SLE transmission in south Florida in the early summer of 1990, eight weeks prior to the first human case. While it is impossible to prevent all arboviral cases in humans, domestic animals, and wildlife, it is possible, through early warning, to mitigate the impact that these important pathogens have on the economy of Florida and to more appropriately manage the health and well-being of Florida residents. The purpose of this proposal is to continue the University of Florida, FMEL research dealing with the monitoring and prediction of mosquito-borne disease outbreaks within the state.

Animal Health Component

85%

Research Effort Categories

Basic

(N/A)

Applied

(N/A)

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
722	0320	1130	25%
722	0320	2050	25%
722	3110	1130	20%
722	3110	2050	30%

Knowledge Area
722 - Zoonotic Diseases and Parasites Affecting Humans;

Subject Of Investigation
0320 - Watersheds; 3110 - Insects;

Field Of Science
1130 - Entomology and acarology; 2050 - Hydrology;

Keywords

arboviral epidemics

water table depth

hydrologic monitoring

st. louis encephalitis virus

west nile virus

Goals / Objectives
1. Continue the real-time quantification and monitoring of biotic and abiotic factors responsible for driving arboviral transmission in Florida. 2. Use a Topographically Based Hydrology model technology to develop a Modeled Water Table Depth surveillance system and surveillance protocol for counties located in North and Panhandle Florida. 3. Create real-time GIS models and risk maps that can be used by mosquito control and public health officials to track and predict vector-born disease outbreaks in humans, domestic animals, and wildlife in Florida.

Project Methods
We will use the dynamic hydrology model described by Stieglitz and colleagues (1997), referred to as the Topographically-Based Hydrology (TBH) model, to simulate variations in WTD at all GEWEX recording sites located north of 29,30 North Latitude in Florida. Each of the counties north of the 29th parallel has multiple GWEX recording stations the data from which are available to us for the studies proposed as part of this CRIS project. The TBH model combines a soil column model, which simulates the vertical movement of water and heat within the soil and between the soil surface plus vegetation and the atmosphere, with the TOPMODEL approach (Beven and Kirkby 1979), which incorporates the statistics of topography to track the horizontal movement of shallow groundwater from the uplands to the lowlands. The model soil column consists of ten soil layers. Diffusion and a modified tipping bucket model govern heat and water flow, respectively. The prognostic variables, heat and water content, are updated at each time step. Transpiration and other surface energy balance calculations use a standard vegetation model (Pitman et al. 1991) that includes bare soil evaporation and canopy interception loss. The Pitman et al. model was updated by Shaman et al. (2002a) to account for the effects of shallow subsurface storm-flow and local variability in depth-to-bedrock readings. Consistent with the TOPMODEL approach, the depth of the soil column water table (WTD) and a probability density function for soil moisture deficit derived from topographic statistics are used to determine the saturated fraction within the watershed (partial contributing area) and groundwater flow discharge at each recording station. This use of TOPMODEL formulations permits the partitioning of runoff and surface water and energy fluxes without the need to model the landscape explicitly. The combined model produces a three-dimensional picture of soil moisture distribution within a catchment. Mean area WTD, as calculated with the TOPMODEL approach, provides an integrated measure of near surface soil wetness. Modeled WTD is measured in meters below the surface. During periods of drought, the WTD is further below the surface (more negative). It is the rise and fall of the water table that determines where and when pools of water form at the land surface, thus creating mosquito larval habitats. As part of this CRIS project we will construct historical and daily real-time WTD profiles for all the GEWEX recording sites in North and Peninsular Florida. This approach is similar to the WTD modeling and arboviral surveillance that we already conduct in Peninsular Florida (Shaman et al., 2005). By constructing a historical WTD data set for the Florida counties that do not already have one, we will be able to more accurately access the risk of arboviral amplification and transmission in the northern half of the state. This will enhance arboviral surveillance programs already in place in North and Panhandle Florida.

Progress 10/01/07 to 09/30/13

Outputs
Target Audience: Target audiences for this project included scientists dealing with medical entomology, vector control, arboviral amplification and transmission, and vector-borne disease transmission cycles; vector control specialists; public health personnel; and government officials (local, regional, statewide, and national) dealing with public health policy determination and implementation; and graduate and undergraduate students interested in vectors and vector-borne disease transmission. The target audience included scientists, vector control specialists, public health officials, and government officials in developing countries, especially in equatorial Central and South America, Africa, India and Pakistan, the Middle East, and the Orient, where vector-borne diseases have a severe impact on the health and well-being of residents and visitors. Efforts to reach the target audience included publishing data generated through this project in peer-reviewed scientific journals, newsletters, and web-based presentations. In addition, presentations at scientific meetings, seminars, and workshops helped to disseminate pertinent information resulting from the studies undertaken as part of this project. Finally, formal classroom lectures, lectures through Distance Education formats, undergraduate mentoring and training and graduate student mentoring and training resulted in the dissemination of new knowledge generated by this project. Changes/Problems: No major changes were implemented or undertaken during the lifetime of this project. What opportunities for training and professional development has the project provided? Formal classroom lectures, lectures through Distance Education formats, undergraduate mentoring and training and graduate student mentoring and training resulted in the dissemination of new knowledge generated by this project. How have the results been disseminated to communities of interest? Target audiences for this project included scientists dealing with medical entomology, vector control, arboviral amplification and transmission, and vector-borne disease transmission cycles; vector control specialists; public health personnel; and government officials (local, regional, statewide, and national) dealing with public health policy determination and implementation; and graduate and undergraduate students interested in vectors and vector-borne disease transmission. The target audience included scientists, vector control specialists, public health officials, and government officials in developing countries, especially in equatorial Central and South America, Africa, India and Pakistan, the Middle East, and the Orient, where vector-borne diseases have a severe impact on the health and well-being of residents and visitors. Efforts to reach the target audience included publishing data generated through this project in peer-reviewed scientific journals, newsletters, and web-based presentations. In addition, presentations at scientific meetings, seminars, and workshops helped to disseminate pertinent information resulting from the studies undertaken as part of this project. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The ability to accurately track mosquito-borne viruses that are transmitted to humans, domestic animals, and wildlife is a critically important component of arboviral surveillance and risk assessment in Florida. The CRIS project for which this termination report is being written was designed to continue a previously developed arboviral surveillance program with the goal of predicting where and when significant numbers of human encephalitis cases would appear in Florida. The FMEL arboviral surveillance protocol focuses on tracking and documenting biotic (arboviruses, mosquito vectors, and avian amplification hosts) and abiotic (rainfall and temperature) factors that are used to predict the spatial and temporal risk of local arboviral transmission. The activities associated with this CRIS project (2008-2013) included the real time tracking of biotic factors including arboviral transmission rates (sentinel chicken, equine, and human seroconversions and cases of disease), vector mosquito abundance and population age structure, and wild avian amplification host abundance, reproductive rate, and population age structure). Abiotic factors including rainfall, water table levels, and surface moisture important to arboviral amplification and transmission were also tracked in real time throughout the study period. During the project 18 training events were conducted by FMEL faculty and staff. This training was designed to convey newly developed arboviral surveillance information to vector control workers and public health personnel primarily from Florida. This project yielded a number of arboviral surveillance-related products designed to modernize the prediction of arboviral outbreaks. Long term collaborations with climatologists and hydrologists at Columbia University resulted from the work done as part of this project. New techniques for tracking and for the visual presentation of surveillance data resulted from this project. Information transfer concerning historical data sets and the real time risk assessment of arboviral transmission in Florida was facilitated through data sets and risk maps that are updated regularly at The Florida Medical Entomology Laboratory Mosquito Information Page Water Table Depth GIS Model: http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm Finally, six University of Florida graduate students were associated with this project. The outreach component of this project included newsletter articles, peer reviewed scientific publications, book chapters, presentations as scientific meetings, and presentations at local, regional, and national workshops. This project represents a multiyear commitment by FMEL researchers and has resulted in a change in the way arbovirus transmission risk is monitored, tracked, and reported. Knowledge transfer about the risk of arboviral transmission during this project occurred at many levels from professionals (University, vector control, and public health) to the citizens of Florida. Surveillance technologies developed during this project resulted in new and improved methods of tracking dangerous viruses and reporting when and where transmission risk was the highest. This increased efficiency at tracking and predicting arboviral outbreaks has had an effect on governmental decision making at the local, regional, and state levels. An improved ability to forecast the spatio-temporal dynamics of arboviral transmission results in a more efficient utilization of vector control efforts and public health strategies to manage these outbreaks. Improved surveillance techniques and strategies result in improved decision making at all levels of government. West Nile virus (WNV) continues to pose a threat to Florida residents and visitors. The WNV was introduced into the US in 1999 and rapidly spread across the country. The virus was first detected in Florida in 2001. Major epidemics caused by WNV have been reported throughout the US (North and South Dakota, Colorado, Texas, California, and Arizona). To date, Florida has been spared from a WN epidemic. The ecology, climate, and seasonal meteorological conditions in Florida place the state at high risk for a major West Nile disease epidemic. Ongoing arboviral surveillance programs are essential for tracking WNV and predicting where and when epidemic risk is the highest. The work conducted as part of this project directly impacts the health and well-being of Florida residents and visitors. By implementing the surveillance technologies developed as part of this project it is possible to reduce the risk of human epidemics; a change in knowledge leads to a change in action which leads to a change in how epidemic risk is monitored, reported, and ultimately confronted.

Publications

• Type: Journal Articles Status: Published Year Published: 2013 Citation: Day, J.F., G.K. Ross and C.R. Connelly. 2013. The biology of arvoviral transmission in Florida. Technical Bulletin of the Florida Mosquito Control Association 9:3-12
• Type: Journal Articles Status: Published Year Published: 2012 Citation: Qualls, W.A., J.F. Day, R. Xue, and B.F. Bowers. 2012. Altered behavioral responses of Sindbis virus-infected Aedes aegypti (Diptera: Culicidae) to DEET and non-DEET based insect repellents. Acta Tropica 122:284-290, doi: 10.1016/j.actatropica.2012.01.012.
• Type: Book Chapters Status: Published Year Published: 2013 Citation: Tabachnick, W.J. and J.F. Day. 2013. The impact of climate change on vector-borne arboviral episystems, Chapter ?. In Sunit Singh (editor), Viral Infections and Climate Change. John Wiley &Sons/Wiley Blackwell Press. Pages 21-34. ISBN 978-953-307-344-6.
• Type: Websites Status: Published Year Published: 2012 Citation: Day, J. F., G. K. Ross, and C. Roxanne Connelly. May 3, 2012. The First 2012 Florida Medical Entomology Laboratory Arboviral Epidemic Risk Assessment for Florida can be viewed at:http://mosquito.ifas.ufl.edu/Documents/MWTD/FMEL_AERA_2012_01.pdf General information about the FMEL AERM and archived assessments can be found at: http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm
• Type: Websites Status: Published Year Published: 2012 Citation: Day, J. F., G. K. Ross, and C. Roxanne Connelly. June 15, 2012. The Second 2012 Florida Medical Entomology Laboratory Arboviral Epidemic Risk Assessment for Florida can be viewed at:http://mosquito.ifas.ufl.edu/Documents/MWTD/FMEL_AERA_2012_02.pdf General information about the FMEL AERM and archived assessments can be found at: http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm
• Type: Websites Status: Published Year Published: 2012 Citation: Day, J. F., G. K. Ross, and C. Roxanne Connelly. July 11, 2012. The Third 2012 Florida Medical Entomology Laboratory Arboviral Epidemic Risk Assessment for Florida can be viewed at:http://mosquito.ifas.ufl.edu/Documents/MWTD/FMEL_AERA_2012_03.pdf General information about the FMEL AERM and archived assessments can be found at: http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm
• Type: Websites Status: Published Year Published: 2012 Citation: Day, J. F., G. K. Ross, and C. Roxanne Connelly. August 22, 2012. The Fouth 2012 Florida Medical Entomology Laboratory Arboviral Epidemic Risk Assessment for Florida can be viewed at:http://mosquito.ifas.ufl.edu/Documents/MWTD/FMEL_AERA_2012_04.pdf General information about the FMEL AERM and archived assessments can be found at: http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm
• Type: Websites Status: Published Year Published: 2013 Citation: Day, J. F., G. K. Ross, and C. Roxanne Connelly. April 3, 2013. The First 2013 Florida Medical Entomology Laboratory Arboviral Epidemic Risk Assessment for Florida can be viewed at:http://mosquito.ifas.ufl.edu/Documents/MWTD/FMEL_AERA_2013_01.pdf General information about the FMEL AERM and archived assessments can be found at: http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm

Progress 10/01/11 to 09/30/12

Outputs
OUTPUTS: Surveillance protocols developed at the University of Florida, Florida Medical Entomology Laboratory (FMEL) and designed to forecast mosquito-borne disease transmission risk in Florida were monitored and results were published as four unique updates released by the FMEL between 10-1-11 and 9-30-12. The first update (http://mosquito.ifas.ufl.edu/Documents/MWTD/FMEL_AERA_2012_01.pdf) was released on May 3, 2012 and indicated that there were multiple areas throughout Florida of moderate to high risk for the amplification and transmission of mosquito-borne Flaviviruses including West Nile virus (WNV) and St. Louis encephalitis virus (SLEV). In addition, several high risk areas for the amplification and transmission of encephalitis virus (EEEV) appeared in the western and central Florida Panhandle. The second update (http://mosquito.ifas.ufl.edu/Documents/MWTD/FMEL_AERA_2012_02.pdf) was released on June 15, 2012 and indicated that the same high to moderate risk areas identified in the first update had persisted in Florida through mid-year. It is important to note that the high risk areas identified by the FMEL Arboviral Risk Assessment maps are regions of the state where environmental (rainfall and temperature) and biological (mosquito and wild bird populations) cycle in a way that maximizes the potential of arboviral amplification resulting in epidemic or epizootic disease transmission. The Third FMEL Arboviral Epidemic Risk Assessment (released on 7/11/12) and the Fourth (released on 8/22/12) both indicated that the high risk arboviral amplification and transmission sites throughout Florida were rapidly waning. This led us to believe that the risk of an arboviral epidemic comparable to what was seen during the summer of 2012 in eastern Texas was unlikely to occur in Florida. The FMEL GIS model allows us to measure the spatial and temporal dynamics associated with mosquito reproduction and disease transmission. Four releases of model results were made during the reporting period. A more thorough discussion of arboviral transmission and the FMEL WTD and KBDI GIS models and links to the four 2012 model updates can be found at http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm. Additional information about mosquito-borne disease transmission in Florida including work with modeled Water Table Depth (WTD) for monitoring the risk of epidemic transmission, a summary of 2012 WNV, SLEV, and EEEV activity in Florida, and arboviral transmission animation maps can be viewed at http://mosquito.ifas.ufl.edu/Index.htm. Arboviral surveillance and the timely prediction of significant arboviral transmission events are critically important to the economy of Florida. Arboviral epidemics are disruptive, dangerous, and expensive and past mosquito-borne disease epidemics have severely impacted the Florida economy. Real-time arboviral surveillance and risk prediction is a top research priority at the University of Florida's FMEL. An active, accurate, and timely surveillance program is necessary to monitor continued arboviral transmission and the risk of infection for Florida residents and visitors. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Infection of humans, domestic animals, and wildlife by mosquito transmitted viruses and other pathogens poses a significant public health threat in Florida. The development of long term disease surveillance monitoring protocols at the UF, FMEL allows the real-time prediction and reporting (at http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm) of existing pre-epidemic conditions that suggest epidemic and epizootic transmission is possible. Knowledge and publication of these conditions early in the year provides sufficient time for appropriate public health responses including vector control, media contact, and the issuance of Medical Advisories and Medical Alerts prior to the onset of epidemic and epizootic disease transmission.

Publications

• Qualls, W.A., J.F. Day, R. Xue and B.F. Bowers. 2012. Altered behavioral responses of Sindbis virus-infected Aedes aegypti (Diptera: Culicidae) to DEET and non-DEET based insect repellents. ACTA Tropica 122:284-290.
• Qualls, W.A., J.F. Day, R. Xue and B.F. Bowers. 2012. Sindbis virus infection alters blood feeding responses and DEET repellency in Aedes aegypti (Diptera: Culicidae). Journal of Medical Entomology 49 (2): 418-423.

Progress 10/01/10 to 09/30/11

Outputs
OUTPUTS: Studies designed to forecast mosquito-borne disease transmission in Florida continued at the Florida Medical Entomology Laboratory (FMEL) from 10-1-10 through 9-30-11. For the first time since 2005 a concentrated outbreak of human West Nile cases caused by the transmission of West Nile virus (WNV) was reported in the state. The outbreak occurred in Duval County in residential areas surrounding the city of Jacksonville. In addition, a significant St. Louis encephalitis virus (SLEV) transmission event was reported in sentinel chickens maintained in and around St. Petersburg by Pinellas County Mosquito Control. Eastern equine encephalitis virus (EEEV) transmission was at a 10 year low in Florida during the study period. Autochthonous dengue transmission moved from the 2009 and 2010 transmission focus in Key West to many adjacent south Florida Counties including Dade, Broward, Hillsborough, and Martin. The greatly elevated transmission levels of WNV and SLEV along with the mild temperatures reported in Florida during the winter of 2011/2012 may be a precursor of elevated arboviral transmission throughout Florida during the 2012 transmission season. Future transmission events will be determined by environmental conditions, especially rainfall patterns, reported throughout the state during the first half of 2012. The spread of autochthonous dengue transmission to multiple south Florida counties is problematic. Florida has a history of significant dengue outbreaks, and the localized transmission of this dangerous virus in south Florida suggests that this region of the state may now be primed for a major outbreak. We have developed an FMEL GIS model to monitor and forecast mosquito-borne disease transmission throughout Florida. The FMEL GIS model allows us to measure the spatial and temporal dynamics associated with mosquito reproduction and disease transmission. Three releases of model results were made during the reporting period. A more thorough discussion of arboviral transmission and the FMEL WTD and KBDI GIS models and links to the three model updates can be found at http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm. Additional information about mosquito-borne disease transmission in Florida including work with modeled Water Table Depth (WTD) for monitoring the risk of epidemic transmission, a summary of 2011 WNV, SLEV, and EEEV activity in Florida, and arboviral transmission animation maps can be viewed at http://mosquito.ifas.ufl.edu/Index.htm. Arboviral surveillance and the timely prediction of significant arboviral transmission events are critically important to the economy of Florida. Arboviral epidemics are disruptive, dangerous, and expensive and past mosquito-borne disease epidemics have severely impacted the Florida economy. Real-time arboviral surveillance is a top research priority at the University of Florida's FMEL. An active, accurate, and timely surveillance program is necessary to monitor continued arboviral transmission and the risk of infection for Florida residents and visitors. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Infection of humans, domestic animals, and wildlife by mosquito transmitted viruses and other pathogens poses a significant public health threat in Florida. The development of long term disease surveillance protocols at the UF, FMEL allows the real-time prediction and reporting (at http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm) of pre-epidemic conditions providing sufficient time for appropriate public health responses including vector control, media contact, and the issuance of Medical Advisories and Medical Alerts prior to the onset of epidemic and epizootic disease transmission.

Publications

• Tabachnick, W.J., W.R. Harvey, J.J. Becnel, G.G. Clark, R. Connelly, J.F. Day, P.J. Linser and K.J. Linthicum. 2011. Countering a bioterrorist introduction of pathogen-infected mosquitoes through mosquito control. Journal of the American Mosquito Control Association 27 (2): 175-177.
• Qualls, W.A., J.F. Day, R. Xue and B.F. Bowers. 2011. Altered response to DEET repellent after infection of Aedes aegypti (Diptera: Culicidae) with Sindbis virus. Journal of Medical Entomology 48 (6): 1226-1230.
• Day, J.F. and J. Shaman. 2011. Mosquito-borne arboviral surveillance and the prediction of disease outbreaks, Chapter 6. In Daneil Ruzek (editor), Flavivirus Encephalitis. InTech-Open Access Publisher, 478pp., ISBN 978-953-307-344-6.

Progress 10/01/09 to 09/30/10

Outputs
OUTPUTS: Studies designed to forecast mosquito-borne virus transmission in Florida continued at the Florida Medical Entomology Laboratory (FMEL) from 10-1-09 through 9-30-10. West Nile virus (WNV) transmission in Florida has been consistently low since 2004. However, transmission levels, as measured by WN antibody-positive sentinel chickens and WN-positive horses rebounded to levels not previously seen in central and south Florida during the autumn of 2010. The most likely reason for this is that environmental conditions that support the efficient amplification of WNV in mosquito vectors and wild avian amplification hosts were observed throughout the state in 2010. These environmental conditions include rainfall patterns that support mosquito and avian reproductive cycles and elevated ambient temperatures that accelerate WNV reproduction in mosquito vectors. Transmission of eastern equine encephalitis virus (EEEV) was also above normal during 2010. In addition, transmission of EEEV to Florida horses was shifted from north Florida to central and south Florida during the spring of 2010. The reasons for this unusual southern shift are unclear but may center on the impact of an unusually cold 2009/2010 winter and spring. The cold spring temperatures may have stopped migrating birds from Central and South America in south Florida where EEEV transmission foci were established in habitats where EEEV transmission has not previously been reported. As has been the case for the past 10 years, amplification and transmission of St. Louis encephalitis virus has remained at below normal levels. This is likely because the environmental conditions necessary to enhance the amplification of SLEV have been absent throughout Florida since the 2000. We have developed an FMEL GIS model to monitor and forecast arboviral transmission throughout Florida. The FMEL GIS model allows us to measure the spatial and temporal dynamics associated with arboviral transmission throughout Florida. Eight releases of model results were made during the reporting period. A more thorough discussion of arboviral transmission and the FMEL WTD GIS model and links to the eight model updates can be found at http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm. Additional information about mosquito-borne disease transmission in Florida including work with modeled Water Table Depth (WTD) for monitoring the risk of epidemic transmission, a summary of 2010 WNV and EEEV activity in Florida, and arboviral transmission animation maps can be viewed at http://mosquito.ifas.ufl.edu/Index.htm. Arboviral surveillance and the timely prediction of significant arboviral transmission events are critically important to the economy of Florida. Arboviral epidemics are disruptive, dangerous, and expensive and past mosquito-borne disease epidemics have severely impacted the Florida economy. Real-time arboviral surveillance is a top research priority at the University of Florida's FMEL. An active, accurate, and timely surveillance program is necessary to monitor continued arboviral transmission and the risk of infection for Florida residents and visitors. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Infection of humans, domestic animals, and wildlife by mosquito transmitted viruses poses a significant public health threat in Florida. The development of long-term surveillance protocols at the UF, FMEL allows the real-time prediction and reporting (at http://eis.ifas.ufl.edu) of pre-epidemic conditions allowing sufficient time for appropriate public health responses including vector control, media contact, and the issuance of Medical Advisories and Medical Alerts prior to the onset of epidemic and epizootic arboviral transmission.

Publications

• Shaman, J., J.F. Day and N. Komar. 2010. Hydrologic conditions describe West Nile virus risk in Colorado. International Journal of Environmental Research and Public Health 7:494-508; doi:10.3390/ijerph7020494.
• Day, J.F. 2010. A brief history of St. Louis encephalitis virus in Florida. Florida Journal of Environmental Health 205 (Spring 2010):21-25.
• Day, J.F. 2010. "Surveillance, prevention and control of vector-borne infections" In Edman, J. (ed.), Vector-Borne Diseases: The Biomedical & Life Sciences Collection, Henry Stewart Talks Ltd, London (http://hstalks.comt=BL1182831-Day).

Progress 10/01/08 to 09/30/09

Outputs
OUTPUTS: Studies designed to forecast mosquito-borne encephalitis transmission in Florida continued at the Florida Medical Entomology Laboratory (FMEL) from 10-1-08 through 9-30-09. West Nile virus (WNV) transmission in Florida has been consistently low since 2004. The most likely reason for this is that the environmental conditions necessary to enhance arboviral amplification to levels sufficient to support epidemic and epizootic transmission have been absent throughout Florida since the 2003 arboviral transmission season. However, WNV transmission to sentinel chickens and horses began to resurge during the autumn of 2009. In addition, three human WN cases were reported in Florida during 2009 (one each in Dade, Lee, and Clay Counties). This suggests that the environmental conditions conducive to WNV amplification and transmission may be cycling up and that this more efficient amplification of WNV may lead to an increase in the number of human cases during the coming year. Transmission of eastern equine encephalitis virus (EEEV) was slightly above normal during 2009. As has been the case for the past 10 years, amplification and transmission of St. Louis encephalitis virus has remained at below normal levels. This is likely because the environmental conditions necessary to enhance the amplification of SLEV have been absent throughout Florida since the 2000. In addition, the introduction of WNV into Florida in 2001 resulted in completion between SLEV and WNV for avian amplification hosts. As evidenced throughout much of North America, WNV out competes SLEV where the two are sympatric. We have developed an FMEL GIS model to monitor and forecast arboviral transmission throughout Florida. The FMEL GIS model allows us to measure the spatial and temporal dynamics associated with arboviral transmission throughout Florida. A more thorough discussion of arboviral transmission and the FMEL WTD GIS model can be found at http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm. The cumulative human WN epicurve for Florida (2001-2009) along with the 2009 FMEL Encephalitis Information System arboviral transmission risk maps can be viewed at http://eis.ifas.ufl.edu. Additional information about mosquito-borne disease transmission in Florida including work with modeled Water Table Depth (WTD) for monitoring the risk of epidemic transmission, a summary of 2009 EEEV activity in Florida, and arboviral transmission animation maps can be viewed at http://mosquito.ifas.ufl.edu/Index.htm. Arboviral surveillance and the timely prediction of significant arboviral transmission events are critically important to the economy of Florida. Arboviral epidemics are disruptive, dangerous, and expensive and past mosquito-borne disease epidemics have severely impacted the Florida economy. Real-time arboviral surveillance is a top research priority at the University of Florida's FMEL. An active, accurate, and timely surveillance program is necessary to monitor continued arboviral transmission and the risk of infection for Florida residents and visitors. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Infection of humans, domestic animals, and wildlife by mosquito transmitted viruses poses a significant public health threat in Florida. The development of long-term surveillance protocols at the UF, FMEL allows the real-time prediction and reporting (at http://eis.ifas.ufl.edu) of pre-epidemic conditions allowing sufficient time for appropriate public health responses including vector control, media contact, and the issuance of Medical Advisories and Medical Alerts prior to the onset of epidemic and epizootic arboviral transmission.

Publications

• Day, J.F. 2008. A brief history of dengue virus in Florida. Florida Journal of Environmental Health 201 (Winter 2008):7-10.
• Connelly, R., J.F. Day and C. Lord. 2008. Competition as a teaching tool. Wing Beats 19 (4):4-9.
• Day, J. F. 2009. Disease surveillance, outbreaks, and control in Florida, Chapter 8. In, C.R. Connelly and D.B. Carlson (Eds.), Florida Mosquito Control: The state of the mission as defined by mosquito controllers, regulators, and environmental managers, Florida Coordinating Council on Mosquito Control, University of Florida, Institute of Food and Agricultural Sciences, Florida Medical Entomology Laboratory, Vero Beach, Florida, 259pp.
• Day, J.F. and J. Shaman. 2009. Severe winter freezes enhance St. Louis encephalitis virus amplification and epidemic transmission in peninsular Florida. Journal of Medical Entomology 46(6):1498-1506.

Progress 10/01/07 to 09/30/08

Outputs
OUTPUTS: Studies designed to forecast mosquito-borne encephalitis transmission in Florida continued at the Florida Medical Entomology Laboratory (FMEL) from 10-1-07 through 9-30-08. West Nile virus (WNV) transmission in Florida has been below normal since 2004. The most likely reason for this is that the environmental conditions necessary to enhance arboviral amplification to levels sufficient to support epidemic and epizootic transmission have been absent throughout Florida since the 2003 arboviral transmission season. Transmission of eastern equine encephalitis virus (EEEV) was above normal during the first two quarters of 2008. This led to an expanded EEEV surveillance effort at the FMEL during the summer of 2008. We dedicated much of the 07/08 fiscal year at the FMEL to monitoring EEEV amplification, transmission, and epidemic risk with the aid of a GIS model designed to evaluate the local risk of arboviral transmission throughout peninsular Florida. During 2008, the GIS model, which formally covered only peninsular Florida, was expanded to include north Florida and the Florida Panhandle allowing us to track EEEV transmission in real-time. This allowed us to accurately determine the spatial and temporal dynamics associated with the 2008 EEEV transmission event in Florida. By comparing the 2008 EEEV transmission data to historical data sets we were able to determine in mid-June that the highly elevated early season EEEV transmission was unlikely to continue into the summer months at the same rate observed early in the year. These data were presented at a meeting of the Florida West Nile Partner's group on June 23, 2008 where it was determined that the risk of a major EEE outbreak in Florida was low. The transmission of EEEV steadily abated through the summer and early autumn months and transmission levels remained normal throughout the remainder of the year. A more thorough discussion of arboviral transmission and the FMEL WTD GIS model can be found at http://mosquito.ifas.ufl.edu/MWTD_Risk_Model.htm. The cumulative human WN epicurve for Florida (2001-2008) along with the 2008 FMEL Encephalitis Information System arboviral transmission risk maps can be viewed at http://eis.ifas.ufl.edu. Additional information about mosquito-borne disease transmission in Florida including work with modeled Water Table Depth (WTD) for monitoring the risk of epidemic transmission, a summary of 2008 EEEV activity in Florida, and arboviral transmission animation maps can be viewed at http://mosquito.ifas.ufl.edu/Index.htm. Arboviral surveillance and the timely prediction of significant arboviral transmission events are critically important to the economy of Florida. Arboviral epidemics are disruptive, dangerous, and expensive and past mosquito-borne disease epidemics have severely impacted the Florida economy. Real-time arboviral surveillance is a top research priority at the University of Florida's FMEL. An active, accurate, and timely surveillance program is necessary to monitor continued arboviral transmission and the risk of infection for Florida residents and visitors. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
Infection of humans and domestic animals by mosquito transmitted viruses poses a significant public health threat in Florida. The development of long-term surveillance protocols at the FMEL allows the real-time prediction and reporting (at http://eis.ifas.ufl.edu) of pre-epidemic conditions, thus allowing sufficient time for appropriate public health responses including vector control, media contact, and issuance of Medical Advisories and Medical Alerts prior to the onset of epidemic and epizootic arboviral transmission.

Publications

• Shaman, J. and J.F. Day. 2007. Reproductive phase locking of mosquito populations in response to rainfall frequency. PloS One 2(3): e331. doi: 10.1371/journal.pone.0000331.
• Darsie, R.F. and J.F. Day. 2007. Redescription of the pupa of Culex restuans and a comparison with Culex nigripalpus. Journal of the American Mosquito Control Association 23(2):95-98.
• Day, J.F. and J. Shaman. 2008. Using hydrologic conditions to track the risk of focal and epidemic arboviral transmission in peninsular Florida. Journal of Medical Entomology 45(3):458-469.
• Vitek, C.J., S.L. Richards, C.N. Mores, J.F. Day and C.C. Lord. 2008. Arbovirus transmission by Culex nigripalpus Theobald in Florida, 2005. Journal of Medical Entomology 45(3):483-493. Day, J.F. 2008. In My Opinion: Chikungunya virus in Florida: Lessons from Italy, 2007. Florida Journal of Environmental Health 199 (Summer 2008):11-14.