Bloodsuckers in the woods... Lyric Bartholomay Associate Professor Department of Entomology Iowa State University

Bloodsuckers in the woods... Lyric Bartholomay Associate Professor Department of Entomology Iowa State University

Characteristics Adapted for ectoparasitism: Dorsoventrally flattened Protective exoskeleton Hypostome (mouthparts) Metamorphosis Egg-larva-nymph-adult # of legs varies with life stage Larvae w/ 6 legs Adults and nymphs w/ 8 legs

Hard Ticks

Hard Ticks Life cycle 1. Four life stages a. Egg, larva, nymph, adult 2. Mate on host 3. Female lays thousands of eggs 4. Female dies after oviposition

Hard Ticks One-host ticks - Entire life cycle on one host Two-host ticks - Larva and nymph on one host; adult on separate host

Hard Ticks, cont. Three-host ticks - Larva, nymph, and adult on separate hosts - Includes most hard ticks

Soft Ticks Images provided by Dr. Philip McCall, Liverpool School of Tropical Medicine, UK

Soft Ticks Life cycle 1. Similar to hard ticks except: a. Several nymph stages b. Mate off of host c. Shorter feeding times d. Females feed several times

Tick-borne diseases close to home

Iowa Lyme Disease Surveillance

Documented tick-borne diseases of Iowa since 1990 Tick Pathogen Disease Reference A.a. Ehrlichia chaffeensis Human monocytotropic ehrlichiosis (Mixson, et al. 2006) "Rickettsia amblyommii" (Mixson, et al. 2006) Francisella tularensis Tularemia (CDC 2002) D.v. I.s. Rickettsia rickettsii Rocky Mountain spotted fever (Iowa DPH 2010) Francisella tularensis Tularemia (CDC 2002) Anaplasma phagocytophilum Human granulocytic anaplasmosis (HGA) (Rainwater, et al. 2006) Borrelia burgdorferi Lyme disease (Lingren, et al. 2005) Possible but undocumented tick-borne diseases of Iowa A.a. "Borrelia lonestari" Southern tick-associated rash illness (STARI) Ehrlichia ewingii Canine and human granulocytic ehrlichiosis I.s. Babesia microti Human babesiosis

Ticks of Iowa

Infection Status Iowa ticks sampled 2007-2009 Site location Total nymphs B. burgdorferi infected % infected B. burgdorferi Anaplasma infected % infected Anaplasma Allamakee Co. 20 4 20% 8 40% Clayton Co. 53 23 43.4% 13 24.5% Delaware Co. 4 0 0% 3 75% Dubuque Co. 1 0 0% 0 0% Johnson Co. 14 0 0% 3 21.4% Linn Co. 12 2 16.6% 3 25% Muscatine Co. 19 1 5.6% 3 15.8% Winneshiek Co. 35 5 14.3% 14 40% Total 158 35 22.2% 47 29.8%

Lyme Disease The most frequently reported arthropod-borne disease in the U.S. KEY PLAYERS: Ixodes scapularis Borrelia burgdorferi Peromyscus leucopus Odocoileus virginianus

Life cycle of ticks involved in B. burgdoferi transmission * *Recall that the tick formerly know as Ixodes dammini, is now called I. scapularis

Seasonal activity of I. scapularis by stage expressed as a percentage of total yearly activity based on data collected in Iowa 1990-2010.

Clinical Signs of Disease bull s-eye rash

Clinical Signs of Disease bull s-eye rash

Clinical Signs of Disease the spectrum

Reported Cases of Lyme Disease by Year, United States, 2003-2012. www.cdc.gov

Human cases of Lyme disease - IA New cases of Lyme disease in Iowa 140 120 New Lyme disease cases 100 80 60 40 20 0 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Year Data were provided by the Iowa Dept. of Public Health

Average Annual Incidence of Reported Cases of Lyme Disease by Age Group and Sex, United States, 2001-2010. Although persons of all ages and gender are susceptible to tick bite, Lyme disease is most common among boys aged 5-9. www.cdc.gov

Lyme Disease CONTROL

Know the RISK

Risk Assessment in Iowa What species of ticks do we most frequently encounter in Iowa? If you found a tick and wanted to have it identified, where would you send it?

Identification of Medically Important Adult Ticks of Iowa Ixodes scapularis female Amblyomma americanum female Dermacentor variabilis female

Goals Recognize major diagnostic characters of hard ticks Identify life stage adult, nymph, or larva Identify adult specimens of major species based on characters of the genera Determine sex of adult ticks

Festoons Diagnostic characters

Life stage - adult Adult ticks are larger than immature forms and all characters are fully developed. The genital aperture is present and distinct. Amblyomma americanum adult female Genital aperture SEM Genital aperture close-up

Life stage - nymph Nymphal ticks lack a well-defined genital aperture although it may appear as a tiny pore. Like adult ticks, they possess 8 legs, but are significantly smaller in overall size. Ixodes scapularis nymph

Life stage - larva Dermacentor variabilis larva Ixodes scapularis larva Larval ticks (and the larvae of other mites) have 6 legs rather than 8, allowing for easy microscopic identification of this life stage.

Genus ID basis capituli and mouthparts Amblyomma Mouthparts long. Palpal segment III is much smaller than palpal segment II. Segment II is always longer than broad. Basis capitulum rectangular. III II Dermacentor Palps are wider than they are long. Basis capitulum and mouthparts have a pliers look. Basis capitulum rectangular. Ixodes III II Palpal segments II and III are sub equal (almost equal) in size. The basis capitulum is usually more trapezoidal than rectangular in shape.

Genus ID Anal Groove Amblyomma & Dermacentor Ixodes Groove is posterior to anus Groove present anterior of anus

Genus ID Other features Festoons Eyes Both A. americanum and D. variabilis possess 11 festoons. All Ixodes lack festoons. Amblyomma and Dermacentor have eyes on the lateral margins of the scutum. Ixodes lack eyes.

Ixodes scapularis a.k.a. blacklegged tick or deer tick In females (and immature ticks) the scutum extends approximately half-way down the body allowing the abdomen to expand upon engorgement. In males, the scutum covers the entire dorsal surface posterior to the basis capitulum.

Amblyomma americanum a.k.a. lone star tick

Dermacentor variabilis a.k.a. American dog tick or wood tick

Promptly Remove Ticks

Lyme Disease CONTROL

Title: Control of arthropod vectors of parasitic diseases Document Type and Number: United States Patent 6849266 Abstract: The present invention provides a method for controlling ectoparasites of small rodents, thereby preventing the transmission of diseases by arthropod vectors. The invention further provides an enclosure having openings for entry of rodents, and having arranged therein one or more applicators which are configured to contact rodents entering the chamber and having an ectoparasiticide on the applicator for application to the rodents.

Bloodsuckers in the woods... Mossies...

Aedes triseriatus the Eastern Tree Hole Mosquito

Dead end Venereal transmission Transovarial transmission Infected eggs overwinter

LaCrosse Encephalitis & LACV A leading cause of infectious pediatric encephalitis Most often seen in Midwestern and Mid-Atlantic states Prior to WNV, most commonly reported arbovirus in U.S. Long-term consequences of infection Seizures Learning disabilities Cognitive defects Boy dies from LaCrosse encephalitis Fifteen-year-old Christopher Doyle died Aug. 11 2006 from LaCrosse encephalitis. He died just 10 days before he was to start his freshman year at North Side High School. Fort Wayne, IN.

Data from Iowa mosquito-borne disease surveillance program 1966-2006

LaCrosse Encephalitis Human cases: Avg. 77/yr Human Cases Reported from 28 States

Lyric Bartholomay Principal Investigator Lab Managers Iowa Department of Public Health Centers for Disease Control