Rapid Mosquito and Mosquito-Borne Virus Surveillance after Floods in Kansas, July August 2007 Bruce Harrison and Parker Whitt PHPM, NC DENR, Winston-Salem, NC
ACKNOWLEDGMENTS TOO NUMEROUS TO LIST -From: NC Emergency Management KS Emergency Management KS Dept. of Health and Environment NC Public Health Pest Management NC Dept. of Environment and Nat. Resources Montgomery Co. personnel 12 Wilson Co. personnel 1 Elk Co. personnel 1 Neosho Co. personnel 1 FEMA personnel 3 Local EMAC personnel -10
Background Information Kansas Department of Health and Environment (KDHE) reduced support for most mosquito surveillance and control programs in early 2007 because of CDC West Nile grant fund reductions. Heavy rain (18 +inches) occurs in southeastern KS over several days in early July, flooding over 600 homes and businesses in 4 counties. No trained KS mosquito personnel or equipment available for surveillance. No CDC personnel available to assist. Kansas requests assistance through Emergency Management System. North Carolina selected by KDHE to send team of two people on an EMAC mission to SE Kansas.
Mission Statement. To conduct rapid mosquito surveillance in the 4 disaster counties. To survey, collect, identify, and pool 4 Culex species for RT PCR virus assays at CDC, Fort Collins, CO, for SLE, WE, and WN viruses To survey, collect, and identify mosquito species causing biting complaints To respond to mosquito complaints and provide information to help eliminate the problem species and preventive measures to protect the people To participate in media requests and provide information for the public
Methods and Equipment Survey not designed as research project, but as a rapid (10 day) assessment to determine effects of the flood and heavy rains on the post-flood mosquito and virus activity in the disaster area. Team to survey 4 counties and select productive trap sites that will provide the most mosquitoes If trap sites not productive, traps were moved to new or known productive sites Traps used: CDC light traps supplemented with CO 2 John Hock gravid traps BioQuip Reiter gravid traps
FOUR COUNTY AREA OF RESPONSE IN KANSAS
Elk, Fall, Neosho, and Vertigris River Systems
TRIP: 21 JULY 5 AUGUST Logistics - 16 days - 2 people - no equipment on site all transported from Winston-Salem - 2 fully loaded vehicles - 2 days drive to Kansas = 1,150 miles - 10 consecutive nights of trapping and processing next day - 1 day for wrap-up and packing - 2 days drive back to NC = 1,150 miles - additional mileage on site = > 600 miles Total work hours = 405 hours for 2 people
Welcome to Kansas Emergency Operations Center Our Shop
TRAP RESULTS 17 traps set each night 34 deep cell batteries, but 17 had to be charging each day Paper collection records kept per trap, then converted to electronic records 27 trap sites used in 4 counties by end of trip 151 trap-night collections over 10 nights 10,375 female mosquitoes collected in traps 62 (41%) trap-nights from CDC/CO 2 =6,930 specimens =111.8 specimens per CDC trap-night 89 (59%) trap-nights from Gravid traps =3,445 specimens =38.7 specimens per Gravid trap-night
MOSQUITO INFORMATION 10,512 females collected, includes trap results and 137 from landing collections 29 species of 54 recognized in Kansas, including a new record = Ps. mathesoni 7 species made up 90.7% of total Ae. vexans = 38.2% Cx. pipiens complex = 26.6% Ae. albopictus = 8.3% Cx. erraticus = 6.7% Cx. salinarius = 4.3% Oc. trivittatus = 3.5% Ps. columbiae = 3.1% 4,068 (38.7%) were 4 Culex species for pooling, includes 3 above and Cx. restuans 2,795 (68.7%) of pooled Culex were Cx. pipiens comp.
POOLING DATA 235 pools (4,068 specimens) from 27 sites in 4 counties -12.8% (30/235) of pools WNV positive -25.3% (21/83) of pools from Montgomery Co. WNV pos. -12.1% (7/58) pools from Wilson Co. WNV positive -3.4% (2/59) pools from Neosho Co. WNV positive -0.0% (0/35) pools from Elk Co. WNV positive -37.0% (10/27) of total sites collected WNV positive -WNV positive pools on 9 of 10 collection days! -No pools were SLE or WE positive!
WNV Positive Species Data Culex No. of No. of Pos. Infect. Rates Species spec. spec./pool Pools Pools MIR MLE 1 pipiens 2,795 30.05 93 27 9.66 (Montg.) 1,867 51.86 36 21 11.25 22.57 (site 10) 1,620 70.43 23 18 11.11 (Wilson) 695 21.72 32 6 8.63 10.72 salinarius 454 7.83 57 2 4.40 (Neosho) 317 12.68 25 2 6.31 6.01 erraticus 705 11.75 60 1 1.42 (Wilson) 488 34.86 14 1 2.05 1.94 restuans 114 4.38 25 0 - - 1 Bias corrected MLE calculated at CDC
West Nile Virus Hot Spot
West Nile Hot Spot (Cont.)
Interesting Observations and Collections Mosquitoes -An. barberi -4 -Cx. tarsalis -5 -Oc. epactius -50 -Oc. dupreei -4 -Oc. hendersoni -2 -Ps. discolor -6 -Ps. longipalpus -9 -Ps. mathesoni - 2 Birds, Snakes, & Animals -Scissor-tailed flycatcher -Yellow headed blackbird -Western kingbird -Eurasian collared dove -Bullsnake -Nine-banded Armadillo
SUMMARY Mission accomplished (pools, pests, media, and complaints) 30 pools found positive for WN virus Identified two hot spots for WN virus Determined flood waters were not direct cause of mosquito problems, but it was containers, temporary pools, and ditches affected by rain water, and drainage water from grain storage 29 species of mosquitoes collected, including one new species record for Kansas Very enjoyable professionally, but must be prepared to work very long intense hours during a very short period under inconvenient conditions Real Learning Experience! Recommend that others from our area volunteer for such missions.
This is what a Southeast Kansas Mile Marker Looks Like!