Risk of Deer Ticks and TBD in the New England Landscape

Transcription

1 Risk of Deer Ticks and TBD in the New England Landscape

2 ~Fifteen Species of Ticks in northern New England (NNE) Four of major veterinary or public health concern Ixodes scapularis the deer tick LD, AP, BA Ix. cookei the woodchuck tick POW virus Dermacentor variabilis the dog tick RMSF Amblyomma americanum the Lone Star tick* * Not established in NNE - YET!

3 Ticks and Lyme Disease The deer tick (or black-legged) tick = the only vector of Lyme disease Ticks are not insects, but are arthopods, more closely related to spiders, lobsters, and dust mites Four life stages, with a usual life cycle lasting two years

4 LD Distribution (US) LD an emerging infectious disease!! Centers for Disease Control and Prevention, 2012.

5 Tick Distribution (ME) Ixodes scapularis distribution monitored by a tick submission program through MMCRI and the Maine Forest Service

6 Ticks and Lyme Disease

7 Bite is Worse Than the Bark Hypostome of the deer tick is barbed. Ticks secrete an anesthesia and anticoagulant when biting. To transmit the Lyme bacterium, ticks must feed for at least 36 hours! B A A) Scanning electron microscope (SEM) image of a deer tick. Courtesy of MicroAngela. B. Borrelia burgdorferi spirochete. CDC.

8 Prompt Removal of Ticks Important! Piesman and Dolan (2002). J Med Ent

9 Lyme Disease in Maine Lyme Disease is becoming more widespread in Maine

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11 Seasonality of Cases (US) US Centers for Disease Control

12 Nymph Dog Tick Seasonality NNE

13 Adults Nymph Deer Tick Seasonality NNE YEAR (months) Jan Feb Mar April May June July Aug Sept Oct Nov Dec

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15 Deer Ticks Vs. Dog Ticks Dog ticks have either a white scutum or white racing stripes. Generally, deer ticks prefer woods while dog ticks prefer open habitats. Adult dog ticks are large in the summer while deer tick nymphs are small. If you find ticks in fall or spring, they are probably deer ticks.

16 Deer Ticks Vs. Dog Ticks Dog ticks have either a white scutum (female) or white racing stripes (male).

17 Deer Ticks Vs. Dog Ticks

18 Other Tick-borne Diseases Anaplasmosis (HGA) and babesiosis Spread by deer ticks Very rare in Maine and, generally,not as common as Lyme disease. Symptoms of HGE include fever, headache, malaise, muscle & joint aches, nausea, vomiting, diarrhea, cough,confusion, and occasional rash.

19 Other Tick-borne Diseases Anaplsmosis (HGA) and babesiosis Spread by deer ticks Very rare in Maine and, generally,not as common as Lyme disease. Symptoms of human babesiosis include malaria-like illness characterized by fever, chills, sweats, fatigue, nausea, and vomiting.

20 Other Tick-borne Diseases Powassan/Deer Tick Virus Two distinct lineages Type I Ixodes cookei and mustelids/woodchucks Type II Ixodes scapularis and mice/deer

21 Other Tick-borne Diseases Powassan/Deer Tick Virus 4 human cases , presumptive Type I 1 human case (fatal) 2013, confirmed Type II

22 Outbreak of Powassan Encephalitis - Maine and Vermont, MMWR 50(35);761-4 From , four cases of POW encephalitis were found in Maine and Vermont. Persons were tested for other infections found in the northeast after tests for West Nile virus (WNV) infection were negative.

23 Powassan Virus Powassan virus investigation Positive skunks and raccoons at several of the human case sites An urban or suburban wildlife problem??? Different risk factors for different lineages?

24 Powassan and the Human/ Wildlife Interface At all sites of cases, there was evidence of wildlife habitation or denning adjacent to human occupation of structures of yards Frequently, a lot of debris (old cars, old sheds, construction material, etc)

25 Favorable habitat Deciduous forest Shrub layer Ticks & Habitat

26 Ticks & Habitat Unfavorable habitat Open, dry habitats Conifer (spruce/hemlock) forests

27 Ticks & Habitat Invasives Elias et al (2006) Higher tick counts associated with exotic invasive forest understory than native forest understory or open understory forests.

28 Ticks & Hosts White-tailed deer are THE reproductive stage host for deer ticks. Abundant deer in presentday northeastern North America

29 Deer and Deer Ticks Each deer can have up to 100 ticks at a time! Each fed tick is capable of producing up to 3000 young!

30 Deer and Deer Ticks 500 More deer = the potential for more ticks (Rand et al. 2003). Ticks/Km R 2 = Deer/Km2

31 Deer Reduction Studies -MA -Wilson et al Great Island, MA >2.3/km 2 deer; significant reduction of ticks -Deblinger et al Ipswich, MA. ~7/km 2 deer; one half the tick abundance of pre-cull numbers

32 -Rand et al

33 Deer Reduction Studies - CT -CT DEP CT DEP

34 The Great Debate: Is it the Deer or is it The Mouse?? Mice a reservoir host for sub-adult (larvae and nymphs) I. scapularis but not the only host Chipmunks, squirrels and birds also serve as reservoir hosts

35 The Great Debate: Is it the Deer or is it The Mouse?? Deer a key host for adult I. scapularis - perhaps the sole critical wild host in the northeast for tick reproduction Dogs, cats, foxes incidental Moose???

36 Islesboro Project Community Tick Mgmt Table 1. Flagging effort, numbers of fall-flagged adult deer ticks (Ixodes scapularis ), positivity for Borrelia burgdoferi, the agent of Lyme disease, and Anaplasma phagocytophilum, the agent of anaplasmosis, Flagging B. burgdorferi A. phagocytophilum Time Period Site Date Hours Ticks Ticks/hour Dissected Tested + % Tested + % Fall 2012 Cliff Island, Portland 11/02/ Islesboro 10/26/ Long Island 10/23/ Swan's Island 11/03/ Spring 2012 Swan's Island 05/15/ Fall 2011 Cape Elizabeth Rockland Pownal Wells

37 Tick Control Synthetic pesticide applications Green options botanicals Habitat modification Host reduction strategies

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40 Tick Free Zones

41 When Removing A Tick: Prompt removal is important! Grasp the tick with tweezers close to the skin. Pull gently but firmly until the tick lets go. Do not handle the tick with bare hands Apply antiseptic to the bite.

42 When Removing A Tick: Prompt removal is important! Grasp the tick with tweezers close to the skin. Pull gently but firmly until the tick lets go. Do not use vaseline, alcohol or matches to remove ticks! Apply antiseptic to the bite.

43 Hot pin Butter Vaseline Baby oil Drivers license Expired credit card Finger nails Olive oil Painting the tick with nail polish Lit cigarette Hot match Butane lighters Gasoline kerosene Liquid soap on a cotton ball Spirits on cotton ball Tools (pliers) Peanut Butter Fishing line

44 Tick Management Handbook A great resource on landscape planning to reduce exposure to ticks. /publications/bulletins/b1010.pdf

45 Questions