1 Tick Activity during on the Texas A&M International Campus (Webb County, Texas) David L. Beck, Josué Zavala, Fernando Quintana Webb County, Texas Amblyomma cajennense

2 Presentation Tick Life Cycle Tick Collection Methods Ticks Identified Correlation with Weather Activity Future Directions

3 Tick Life Cycle Tick life cycle includes three stages:  Six Legged Larval  Eight Legged Nymph  Eight Legged Adult Image taken from: J. Zavala

4 Location of Tick Collection Figure 2: Satellite Image of TAMIU Best L. Nunez, D. Beck

5 Tick Collection Methods A. Tick CO 2 Traps Tick traps also know as carbon dioxide (CO 2 ) traps are a white cloth (1m by 0.5m). About 0.25 kg of dry ice is placed in the center of the cloth. The trap is set for three hours. B. Tick Walk/ Drags C. Collection from dogs, hogs, deer, etc.

6 Presentation Tick Life Cycle Tick Collection Methods Ticks Identified Correlation with Weather Activity Future Directions

7 Tick Identification Identification of each tick depends on the following structures: anal groove, palpi (mouth parts), and the spiracle. Each tick is individually examined under the microscope. Figure 8: Tick Identification J. Zavala, J. Perez, S. Mata, E. Montalvo, G. Daves

8 Tick Identification: Genera J. Zavala Note the difference in the anal groove of the Ixodes and non-Ixodes Non-IxodesIxodes Photographs taken by S.J. Upton, Kansas State University

9 Tick Identification: Genus of Non-Ixodid ticks Photographs Taken by S.J. Upton, Kansas State University * Amblyomma eye spots present; Aponomma eye spots absent *Rhipicephalus with festoons; Boophilus festoons absent J. Zavala HaemaphysalisRhipicephalus or Boophilus Amblyomma or Aponomma Dermacentor

10 Ticks Identified March 2005-Nov 2008 No. Found 1. unidentified chigger shown for size comparison. N/A 2. unidentified flea shown for size comparison Amblyomma cajennense Larva Amblyomma cajennense full engorged Larva 5. Amblyomma cajennense Nymph Amblyomma cajennense Adult Male Amblyomma cajennense Adult Female Amblyomma cajennense partially engorged Adult Female 9. Amblyomma inornatum Nymph Amblyomma inornatum Adult Male 55 No. Found 11. Amblyomma inornatum Adult Female Amblyomma inornatum partially engorged Adult Female 13. Amblyomma maculatum Adult Male Amblyomma maculatum Adult Female Dermacentor variabalis Adult Male Dermacentor variabalis Adult Female Dermacentor variabalis fully engorged Adult Female 18. Haemaphysalis leporispalustris Adult Male Haemaphysalis leporispalustris Adult Female 9 Total Speciated D. Beck, J. Zavala, and other students

11 Tick Species A. cajennense is the dominant tick. Tick Species# Collected% of Total Amblyomma cajennense % Amblyomma inornatum % Amblomma maculatum80.02% Amblyomma americanum10.002% Dermacentor albipictus490.1% Dermacentor variabalis920.2% Dermacentor halli10.002% Haemaphysalis leporispalustris440.09%

12 Other Sites A. inornatum and D. variabilis are more abundant at other sites. Table 2: Ticks from other sites CountyWebbJim HoggMaverick Tick Species / Site Amblyomma cajennense Amblyomma inornatum Amblyomma maculatum Dermacentor albipictus Dermacentor variabalis Haemaphysalis leporispalustris

13 What is A. cajennense? Cayenne Tick Tick likes it warm from 29N to 29 (30 N to 30 S)  Southern Texas to Northern Argentina Lacks cold tolerance – killed by a hard freezes Host  Horses, Cattle, and dogs  Primates, Anteaters and Peccary (Javelina)  Medium to large mammals  HUMANS!!!! Avid feeder on humans.

14 Why does A. cajennense do so well in South Texas 50% Mortality of Adult ticks (23°C and 85% Relative Humidity)  A. cajennense days 50% Mortality humidity not reported  A. cajennense days  A. americanum days Under dehydrating conditions (23°C and 35% Relative Humidity)  A. cajennense days

15 What does A. cajennense transmit Rocky Mountain Spotted Fever/Brazilian Spotted Fever Thai tick typhus Human ehrlichiosis Rickettsia amblyomii Venezuelan equine encephalomyelitis virus Q fever (Coxiella burnetti)

16 Presentation Tick Life Cycle Tick Collection Methods Ticks Identified Correlation with Weather Activity Future Directions

17 Correlation with weather Larva  Positive correlation with 3 wk average humidity (p<0.05)  Negative correlation with 3 wk average wind speed (p<0.001)  Negative correlation with maximum wind speed (p<0.05)  Negative correlation with mean temperature (p<0.05)  Negative correlation with 3 wk average mean temperature (not significant) 

18 Larval emergence is seen after significant rain events. (Not Significant)

19 Correlation with weather Nymph  Positive correlation with 3 wk average cloud cover (p<0.01)  Negative correlation with 3 wk average mean temperature (p<0.05) Adults  Negative correlation with 3 wk average humidity (p<0.05)  Positive correlation with 3 wk average Wind Speed (p<0.001)  Positive correlation with wind speed on trap day (p<0.01)  Positive correlation with 3 wk average mean temperature (p<0.05)

20 Note: Different Scale Negative correlation with 3 wk average mean temperature (p<0.05)

21 Note: Different Scale Larval Emergence

22 Note: Different Scale Positive correlation with 3 wk average mean temperature (p<0.05)

23 Note: Different Scale Adults come independent of rain events.

24 Conclusion Larval emergence appears to control the life cycle of A. cajennense in South Texas.  Larva emerge  3-4 months later the nymphs emerge  Adults emerge later (usually during the hotter months).

25 Note: Different Scale

26 Presentation Tick Life Cycle Tick Collection Methods Ticks Identified Correlation with Weather Activity Future Directions

27 Tickborne Disease Detected at TAMIU We examined 189 A. cajennense for  Rickettsia – spotted fever group  Borrelia – Lyme, STARI and others  Ehrlichia – HME, HGE All were negative Prevalence would be <4% for these D. Beck, P. Billingsley, P. Williamson

28 Tickborne Disease Detected at TAMIU We examined 102 Dermacentor variabilis  4+ Rickettsia – spotted fever group  1+ Borrelia – Lyme, STARI and others  0+ Ehrlichia – HME, HGE We detected  4 Rickettsia rhipicephali (2 from a house cat at a colonia, 2 from TAMIU campus)  1 Borrelia lonestari P. Billingsley, P. Williamson, D. Beck

Augustin Elizondo Roberto Flores Leonardo Nunez Ruben Sandoval Fernando Palacios-Bruno Melissa Vela Kimberly Witt Josue Zavala 2006 Marc Andres C. Alberto Bernal Leslie Carreon Eliezar Castenada Monica Contreras Francisco Garcia Alberto Gonzalez, Jr. Maria Hernandez Melissa Martin Larry Miller Fernando Palacios-Bruno Jesus D. Perez Jorge Serrato Lydia Valenzuela Melissa Vela Joey Villereal Josué Zavala Arianne Zecca 2006

Maxine Caballero Francisco Garcia Carlos Gonzalez Eduardo Gonzalez Geraldo Gonzalez Maria Hernandez Abigail Lovano Brenda Perez Jorge Serrato Leonor Araceli Soto Cynthia Villareal Josué Zavala 2008 Maxine Caballero James Cortez Geofrey Daves Francisco Garcia Reynaldo Garcia, III Alissa Gonzalez Maria Hernandez Abigail Lozano Selina Mata Ricardo Medrano, Jr. Eric Montalvo Jessica Perez Jorge Serrato Edna Valadez Richard Jacobsen (Faculty at LCC) Juan Pedro Orozco (MS Biology) Alberto Resendez (MS Biology) 2009 Eric Montalvo Jessica Perez James Cortez Dania Gomez Cesar Cardenas, Jr. Juan Pedro Orozco (MS Biology)

31 Acknowledgments TAMIUUniversity of North Texas Thomas C. VaughanPhillip Williamson C. Neal McReynoldsPeggy Billingsley Mike Daniel Marvin Bennett $$$$ University Minigrants Texas Center Grant 2005, 2006, 2007 Defense Grant # W911NF