Hurricane Rita Vector Control Issues and the DSHS

Response

Diseases In Nature

June 13, 2007

Austin, Texas

Vector Control Issues

Mosquitoes Floodwater mosquitoes Standing water mosquitoes

Mosquitoes

The clock starts ticking when waterflow stops. Time ofemergence is dependent upon species

Hurricane Rita and Mosquito Control Pre-landfall events Landfall Post-landfall events

Pre-landfall Events

State Operations Center (SOC)

DSHS Entomologist

Conferences with State Epidemiologist concerning mosquito control activities following landfall

Conferences with CDC Entomologists offering assistance following landfill

2,000,000 people without electricity for several weeks

Rainfall ranged from 6- 10 inches in some areas

Coastal tidal surges reportedly ranged from 4 – 15 feet

Creation of new mosquito breeding sites

Joint Field Office (JFO)

Restoration of electrical power

Debris removal and clean-up efforts

Mosquito Control: The Science Bionomics of species Documented Mosquito Landing Rate

Counts Data reflect trends

Insecticide Application Too soon = no control Too late = no or little control

Egg deposition sites for salt-marsh mosquitoes

Aedes sollicitans, Salt-Marsh mosquito

Mosquito Landing Rate Count

Locations representative of area Same time Same observer

Number of mosquitoes landing/minute

Mosquito Landing Rate Count

Mosquito Landing Rate Count

Surveillance Demonstrate need for application of

insecticides (FEMA required)

Evaluation Effectiveness of insecticide applications

(FEMA required)

Mosquito Landing Rate Count

Total number of documented adult mosquitoes that land in one minute on the front of one leg from the waist to the foot

FEMA/CDC determine the threshold number

FEMA/CDC set the time frame for mosquito control activities

Mosquito Landing Rate Count

Documented 70+ per minute in Port Arthur, Jefferson

County 40+ per minute in Bridge City, Orange

County 30 per minute in Hardin County

U.S. Air Force Aerial Spraying

Orange, Jefferson, Chambers Counties Documented Pre-spraying mosquito

landing rate counts Documented Post-spraying mosquito

landing rate counts

National Wildlife Areas/Preserves

NO SPRAY ZONES

U.S. Air Force Entomological Field Team Air Force Institute of Operational Health,

Brooks City-Base, Texas Documented Pre-spraying mosquito

landing rate counts Recommended USAF Aerial Spray for

portions of Hardin, Jasper and Newton counties based on their data

Ground ULV Unit

Acknowledgements

Dr.Tom Betz, Acting State Epidemiologist, DSHS

Dr. James Wright, DSHS, PHR 4/5

Acknowledgements

Chambers County Mosquito Control District Lawrence Lewis

Jefferson County Mosquito Control District Lee Chastant

Orange County Mosquito Control District Patrick Beebe

Acknowledgements

CDC Dr. Roger Nasci Dr. Janet McAllister

USAF Major Mark Breidenbaugh, Aerial Spray Flight Dr. Chad McHugh, Entomology Field Team

Leader

DOD Captain John Morning