SCWDS HD Surveillance 11/8/2016. Update on SCWDS Culicoides Surveys in the Southeast. Common Culicoides species in the Southeast U.S.

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1 /8/0 Update on SCWDS Culicoides Surveys in the Southeast >00 sites >7,500 trap-nights WMAs, parks, etc July September CDC light traps Stacey Vigil, Mark Ruder, and Joseph L. Corn Southeastern Cooperative Wildlife Disease Study College of Veterinary Medicine University of Georgia USDA-APHIS-VS funded project to document Culicoides spp. distributions Common Culicoides species in the Southeast U.S. SCWDS HD Surveillance EHDV- Total Culicoides spp. to date: Total spp. from SE (not FL): Total Florida spp.: EHDV- EHDV- BTV- spp. 8 spp. spp. BTV- BTV- BTV- BTV- BTV-7 BTV-8 Reported HD and isolations of EHDV & BTV from wild ruminants Southeastern U.S. Top 5 spp. Florida Top 5 spp. Culicoides sp. % sites present () Culicoides sp. % sites present (78) C. haematopotus* 9% C. insignis % C. debilipalpis* / C. stellifer* 8% C. edeni % C. stellifer* 9% C. paraensis* % C. furens* % C. hinmani % C. haematopotus* % C. insignis 9% C. sonorensis % C. sonorensis % * Proposed as possible vectors of BTV/EHDV Known vector of BTV/EHDV

2 /8/0 Year Trap nights C. insignis most common in FL 0 9 Range increasing in nearby states is increasing 0, C. sonorensis is rare in the Southeast Documented at 0 sites total EHDV BTV EHDV & BTV Hemorrhagic Disease Significant findings: C. stellifer was the most commonly collected species C. sonorensis was not collected in any trap 0-0 Confirmed vectors C. insignis C. sonorensis Known C. sonorensis distribution Suspected vectors C. stellifer Total Culicoides Michigan Culicoides Survey n Percent of total C. stellifer 507 % C. haematopotus 79 % C. crepuscularis 50 % C. venustus 5 % C. biguttatus C. chiopterus C. mulrennani C. obsoletus C. paraensis C. sanguisuga C. spinosus C. variipennis 57 < % ea Culicoides species C. debilipalpis Update on 05- Hemorrhagic Disease Activity in Wild Ruminants SCWDS EHDV & BTV Diagnostics Virus isolation attempts on tissues submitted by state wildlife agencies and diagnostic labs Primarily dead/moribund wild ruminants Primarily spleen, lung, and/or blood Isolates typed by neutralization or RT-PCR Mark G. Ruder, Clara Kienzle, Rebecca L. Poulson, David E. Stallknecht Southeastern Cooperative Wildlife Disease Study Department of Population Health College of Veterinary Medicine University of Georgia

3 /8/0 0 Virus Isolations by SCWDS 05 Virus Isolations by SCWDS viruses isolated from deer in states 57 viruses isolated from WTD in states Virus Total as of October, 0 Virus n EHDV- WV EHDV- AR, GA (), KS (), NE (), NM (), NC (), SC, VA (), WV () EHDV- FL, IL, NM BTV- LA BTV- 9 VA (5), WV () BTV NE State EHDV- AL, FL () EHDV- AL, IN (), KS (9), KY (), LA, MS, MO () EHDV- FL, MO, NC BTV-7 8 ID (), MT (5) 0 BTV- Outbreak State EHDV- EHDV- BTV- First report August 5 VI neg Deer found dead in pond Shenandoah County, VA BTV isolated at SCWDS sent to NVSL Identified as BTV- Reports of dead deer continued through Sept WVDNR and VDGIF personnel continued to investigate and collect diagnostic samples State VA WV Samples for VI Viruses isolated Shenandoah BTV- () Rockingham BTV- () Hardy BTV- () Hampshire County

4 /8/0 0 BTV- Outbreak Hardy Rockingham Hardy Co, WV Shenandoah Co, VA C. Teets, WVDNR State County Samples Viruses Mortality for VI isolated reports Rockingham Co, VA VA Shenandoah BTV- () ~00 Rockingham BTV- () WV Hardy BTV- () ~00 Hampshire 0 BTV- Outbreak Next steps Truly localized or more widespread? Follow-up serological survey from hunter-harvested deer in the area New or old virus? Full genome sequence Culicoides present during and after outbreak? Insect collections mid-sept 0 CDC light traps Hardy County, WV in outbreak area total trap nights Continue during 07??? 0 BTV- Outbreak BTV rarely isolated from WV and VA by SCWDS WV: BTV-0 in Jackson County (0) VA: BTV-0 in Bedford County (00) BTV- not historically endemic serotype of BTV First documented in FL in 999 Has been detected by various labs over wide geographic region Northeastern most report of BTV- Concern for northern expansion Reported BTV NVSL/SCWDS Acknowledgements SCWDS member agencies Cooperative agreement USDA-APHIS-VS WVDNR J Crum, E Barton, C Teets, S Hincks, S Houchins VDGIF M Knox, M Kirchgessner, F Frenzel NCWRC J Allen, D Shaw, M Palamar, G Batts NVSL E Ostlund, D Johnson, & T Sturgill ABADRU B Pfannenstiel, B Wilson, & E Schirtzinger SCWDS staff C McElwee, J Brewton, M Willis, D Shaw, M Walter SCWDS Diagnosticians

5 /8/0 Michigan Culicoides Survey Over the past decade, Michigan has experienced a dramatic increase in confirmed EHD outbreaks Questions? CONFIRMED EHD IN MICHIGAN Kansas Flint Hills Year No. of counties Estimated WTD mortality ,05 00, What are the drivers? Will this trend continue? What Culicoides spp are involved? Detections of exotic BTV from ruminants Michigan Culicoides Survey Since 999 Reported C. sonorensis distribution Objective: Identify the resident Culicoides species in areas of EHD outbreaks in southern Michigan BTV- BTV- BTV- BTV- BTV- BTV- CDC light trap locations July-Sept 0-0 Year Trap nights Total Culicoides 0 9 0, Historically, 5 serotypes of BTV circulated in the US but since 999, exotic BTV serotypes have been detected BTV- BTV- BTV- BTV- BTV- BTV- BTV-5 BTV- BTV-9 BTV- BTV- BTV-8 BTV-9 BTV- BTV- Johnson et al. 00, Gibbs et al. 008; Schirtzinger et al. unpub 5

6 /8/0 SE Culicoides Survey C. insignis Confirmed vectors EHDV BTV EHDV & BTV Hemorrhagic Disease C. sonorensis C. insignis most common species in FL & range in nearby states is increasing C. sonorensis is rare in the Southeast EHDV & BTV Transmission Future directions Entomological investigations of outbreaks Regional Culicoides surveys with animal-baited aspirations Experimental infection of field populations of Culicoides spp. Virus transmission studies using field populations of Culicoides spp. Documented at 0 sites total 0 HD Submissions to SCWDS as of October, 0 99 submissions from wild ruminants in states First detection in New Mexico by SCWDS or NVSL Detected each year since 00 md prong 9 prong bhs md wtd 8 Species Total White-tailed deer 8 Mule deer Pronghorn Bighorn sheep Elk Nilgai (feral) EHDV- year Continue to isolate EHDV- from deer throughout the US wtd elk 5 md wtd nilgai

7 /8/0 HD in the Central Great Plains Nebraska & Kansas 0 HD submissions to SCWDS Kansas VI Results viruses isolated Year County reports 000 EHDV- () Viruses isolated 00 EHDV- (7), BTV-7 () 00 EHDV- () 00 EHDV- (5), BTV-7 () HD in Eastern US West Virginia Serotype diversity EHDV- Pending VI negative Prominent eastern focus for reported HD mortality 05 Dramatic east-west gradients exist in Great Plains 00 EHDV- () 005 EHDV- (5) 00 EHDV- (), BTV-7 () 007 EHDV- () 008 EHDV- (), EHDV- () 009 EHDV- () EHDV- (8), BTV-7 () 0 7 EHDV- (), EHDV- () 0 9 EHDV- () EHDV- () 0 EHDV- () EHDV- Most widespread isolate Larger outbreak in central NC 0 EHDV- outbreak in western NC Example of cryptic event in Athens, GA BTV- WV/VA outbreak EHDV- EHDV- BTV- VI neg EHDV- Outbreak North Carolina EHDV- Outbreak Athens, Georgia Cryptic outbreak on UGA property Whitehall Forest: deer Botanical Garden: deer No other reports Jason Allen, NC Wildl. Res. Comm. 7

8 /8/0 SCWDS EHDV & BTV Diagnostics EHDV & BTV Transmission Future directions Virus isolation attempts Significant gaps exist in our understanding of EHDV and BTV transmission in certain regions of the US Cattle pulmonary artery endothelium passages Serotype identification by virus neutralization or RT-PCR We need to better understand endemic and epidemic transmission cycles 05 HD Submissions to SCWDS 7 submissions from wild ruminants in 9 states 7 WTD 8 WTD MD bison MD moose elk 5 Species White-tailed deer Total 59 Mule deer Elk Key deer Moose Bison 0 WTD MD 8 WTD elk WTD key deer 7 Reported EHDV detections by NVSL & SCWDS

9 /8/0 Michigan Culicoides Survey EHDV- EHDV- EHDV- BTV- BTV- Year Trap nights 0 Total Culicoides 9 0, BTV- BTV- BTV- BTV-7 SEPTEMBER 0 BTV-8 Reported HD and isolations of EHDV and BTV in wild ruminants Species Allegan C. haematopotus C. crepuscularis C. stellifer C. venustus 0 Calhoun Ionia St. Joseph 0 5 Methods CDC UV light traps operated overnight Four locations every - weeks July September Collections into 70% ethanol Morph. identification of Culicoides (Blanton & Wirth 979) 0 0 Ionia St. Joseph Allegan Calhoun 0 Ionia Livingston Branch Cass Muskegon Ionia Livingston Branch St. Joseph Light traps located in clearings adjacent to waterways where dead WTD had been recovered during the 0 EHD outbreak 9

10 /8/0 Results JULY-SEPTEMBER 0 Species Branch Cass Ionia Livingston Muskegon C. stellifer 8 C. haematopotus 9 0 C. crepuscularis 0 C. venustus Other species* 9 5 * C. biguttatus, C. chiopterus, C. mulrennani, C. obsoletus, C. paraensis, C. sanguisuga, C. spinosus, C. variipennis EHDV/BTV transmission AUGUST-SEPTEMBER 0 Branch Ionia Livingston St. Joseph Total Culicoides 5 With such an ecologically diverse country, we should expect a diverse and complex disease ecology. Culicoides Surveys in the Southeast C. sonorensis is uncommon in the Southeast Not the primary vector of orbivurses in this region especially in wild ruminants. Known Culicoides distributions Confirmed and suspected vectors C. insignis a neotropical vector of BTV and is abundant in FL Recent detections north of historical range Orbivirus-Culicoides systems are dynamic Changes in climate, ruminant populations, land-use, etc change will continue to make things exciting. 0

11 /8/0 SCWDS EHDV/BTV Diagnostics Submissions State wildlife management agencies and diagnostic labs Primarily WTD (and other wild and domestic ruminants) Dead or moribund Primarily spleen, lung, and/or blood EHDV- EHDV- BTV- VI neg West Virginia & Virginia Serotype diversity West Virginia EHDV- &- in Appalachian Plateau BTV- in Blue Ridge Virginia EHDV- in Coastal Plain BTV- in Blue Ridge Jason Allen, NC Wildl. Res. Comm. High serotype diversity observed in WV is not typical for this state