Lyme Disease (Borrelia burgdorferi)

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1 Lyme Disease (Borrelia burgdorferi) Rancho Murieta Association Board Meeting August 19, 2014 Kent Fowler, D.V.M. Chief, Animal Health Branch California Department of Food and Agriculture

2 Panel Members California Department of Food and Agriculture (CDFA) Kent Fowler, DVM Branch Chief, Animal Health Branch (AHB) California Department of Public Health (CDPH) Anne Kjemtrup, DVM, MPVM, PhD Epidemiologist in Vector-Borne Diseases Bryan Jackson, PhD - Associate Public Health Biologist California Department of Fish and Wildlife (CDFW) Ben Gonzales, DVM, MPVM Senior Wildlife Veterinarian Helayna Pera - Environmental Scientist (Wildlife) Brian Patrick - Wildlife Officer CDFW

3 Discussion Issues Lyme Disease Background Humans Horses Dogs Cause Transmission Symptoms Diagnosis Prevention Vaccination Treatment Rancho Murieta Deer Population Health Deer Population Interaction with RMA residents

4 A Brief Overview of Lyme Disease In California

California Tick Species 47 species of ticks in

) ticks Ixodes pacificus (western black-legged tick)

Dermacentor occidentalis (Pacific Coast tick)

sanguineus (brown dog tick) Argasid ( soft ) ticks

5 California Tick Species 47 species of ticks in California Only 8 species bite humans Ixodid ( hard ) ticks Ixodes pacificus (western black-legged tick) Dermacentor variabilis (American dog tick) Dermacentor occidentalis (Pacific Coast tick) Dermacentor andersoni (wood tick) Rhipicephalus sanguineus (brown dog tick) Argasid ( soft ) ticks Ornithodoros hermsi Ornithodoros parkeri Ornithodoros coriaceus (Pajahuello tick )

California, western blacklegged tick (Ixodes pacificus) only tick species that transmits

6 Borrelia burgdorferi Lyme Disease Cause of Lyme disease in U.S. * Spirochete bacteria Lyme disease is the most common vector-borne disease in the U.S. In California, western blacklegged tick (Ixodes pacificus) only tick species that transmits LD to people ** * Steere, Wien Klin Wochenschr. (118): ** Lane et al J. Med Entomol. (41):

Early Symptoms of Lyme Disease Non-specific flu-like symptoms Erythema

central clearing Rash typically develops 7-10 days following tick bite

2006;354:2794-801) Reported in about 60% of CA cases EM Rash.

7 Early Symptoms of Lyme Disease Non-specific flu-like symptoms Erythema migrans (EM) rash EM rash is slowly expanding rash that sometimes has central clearing Rash typically develops 7-10 days following tick bite (range 1-30 days) Rash is rarely pruritic (Wormser, N Engl J Med 2006;354: ) Reported in about 60% of CA cases EM Rash. Source: Ross Ritter Rash should not be confused with tick-bite lesions (or allergic response)

8 Neurologic Other Signs of Lyme disease Idiopathic facial palsy (Bell s palsy) Radiculoneuropathy Arthritic Arthritis in one or more joints Cardiac Atrioventricular conduction disturbances, myocarditis, pericarditis

9 Transmission of B. burgdorferi to humans in California larva female lays eggs Ixodes pacificus Life cycle adult female nymph Larvae or nymphal Ixodes pacificua ticks acquire the bacteria by feeding on infected mammal hosts. People are accidentally infected through the bite of an infected nymph or adult female western blacklegged tick.

10 Ixodes pacificus--adult habitat Along trail sides, waiting on vegetation, often on the uphill side of a trail Deciduous hardwood forests

11 Ixodes pacificus: nymphal habitat Leafy under-story in deciduous hardwood forests On fallen logs in hardwood forests Photos courtesy Dr. Robert Lane, UC Berkeley

wait on the ends of grasses for a host to come by and

12 Adult ticks are found on wild grasses and low plants Ticks do not fall from trees, jump or fly Ticks quest or wait on the ends of grasses for a host to come by and brush against the grass Ticks grasp a host with their forelimbs

13 California: Ixodes pacificus Infection Prevalence with B. burgdorferi Adult I. pacificus: 1-5% Nymphal I. pacificus: 0-20% In northern CA where studied, (Mendocino, Placer, Yolo Counties), prevalence is often higher in nymphal than adult ticks* I. pacificus larvae: 0% Larvae rarely bite people * Clover and Lane J. Trop Med Hyg. 53: ; Wright et al J. Med Ent 35: From left to right: Adult female, larva (lower), nymph (above), adult male Ixodes pacificus ticks. Source:CADPH

California: Lizards and Lyme Disease Western fence lizard Larval and nymphal I.

A borreliacidal protein in lizard blood kills Lyme disease spirochetes in the gut of

As a result, in some areas in California, the proportion of infected adult I.

14 California: Lizards and Lyme Disease Western fence lizard Larval and nymphal I. pacificus ticks feed on lizards. A borreliacidal protein in lizard blood kills Lyme disease spirochetes in the gut of infected I. pacificus nymphs. As a result, in some areas in California, the proportion of infected adult I. pacificus ticks is lower than in the nymphal I. pacificus ticks because the blood meal from the lizard cleaned the tick. Lane and Quistad J. Parasitol. 84: 29-34; Salkeld and Lane, 2010 Ecology 91 (1):

15 About 100 reported cases of Lyme disease per year in California

16 Reported cases per 100,000 person-years, * Trinity 5.9 Humboldt 4.3 > 5.0 Mendocino 4.0 Sierra 3.1 Nevada Mono 2.0 Santa Cruz 1.7 Mariposa 1.7 Amador Sonoma 1.4 Marin 1.0 Others No cases reported *Though Lyme disease cases have been reported in nearly every county, cases are reported based on the county of residence, not necessarily the county of infection. Figure 2. Incidence of Lyme disease, by county, California,

17 Interactive Lyme Disease Map:

21 Ixodes scapularis tick female nymph Erythema migrans larva male Ixodes pacificus tick

22 Lyme Disease in Horses Low grade fever Chronic weight loss Sporadic lameness Muscle tenderness Chronically poor performance Arthritis Diverse orthopedic problems Extreme skin hypersensitivity Neurologic signs Uveitis

23 Lyme Disease in Horses/Dogs Diagnosis Antibody based serologic tests difficult to interpret ELISA, Western Blot, IFA PCR Treatment Doxycycline Oxytetracycline Vaccination No licensed vaccines for horses Three (3) vaccines available for dogs Human vaccine on the market for 4 years ( ) LYMErix by SmithKline Beecham

24 Lameness/Health Issues in RM Deer Vesicular Stomatitis* Foot and Mouth Disease* Adenovirus Hemorrhagic Disease* Bluetongue* EHD (Epizootic Hemorrhagic Disease)* Malignant Catarrhal Fever* Foot Rot Lyme Disease Injury Copper Deficiency

25 Issues to Address Concerning Lyme Disease/RM Deer Health Prevalence of lyme disease? Deer ticks species? prevalence + for Lyme Health of deer population? Risk to other livestock/human Possibility to answer these questions with complete workup and necropsy of several deer (4-6) select by lameness/poor health

27 If we really want to get something done, we ll find a way. If we don t, we ll find an excuse.

Thank You! Kent Fowler, D.V.M. Kent.fowler@cdfa.ca.

28 Thank You! Kent Fowler, D.V.M. (916) Chief, Animal Health Branch California Department of Food and Agriculture

Borreliae. Today s topics. Overview of Important Tick-Borne Diseases in California. Surveillance for Lyme and Other Tickborne

Borreliae. Today s topics. Overview of Important Tick-Borne Diseases in California. Surveillance for Lyme and Other Tickborne Surveillance for Lyme and Other Tickborne Diseases in California with emphasis on Laboratory role Anne Kjemtrup, D.V.M., M.P.V.M., Ph.D. Vector-Borne Disease Section California Department of Public Health