The Essentials of Ticks and Tick-borne Diseases Presenter: Bobbi S. Pritt, M.D., M.Sc. Director, Clinical Parasitology Laboratory Co-Director, Vector-borne Diseases Laboratory Services Vice Chair of Education Department of Laboratory Medicine and Pathology Mayo Clinic, Rochester, Minnesota 1
Disclosures None Utilization Message As you view this presentation, consider the following important points regarding testing: How are tests for tick-borne diseases going to be used in your practice? When should the tests be used? How will results impact patient management? 2
Setting the stage (or the forest) Shutterstock Royalty Free stock image Tick Basics Ticks are arachnids (along with mites and spiders) Not insects! 8 legs as adults Divided into hard and soft ticks Laboratory testing is primarily focused on diseases transmitted by hard ticks since these comprise the bulk of tick-borne diseases Ticks have FOUR life cycle stages: egg, larva, nymph, adult, and require a blood meal in order to molt into the next stage 3
Ticks don t have wings They pursue hosts by crawling or questing Questing Ticks Image courtesy of Graham Hickling, PhD CDC Public Health Image Library 4
lxodes scapularis nymphs 5
The Ticks and the Pathogens they carry Rhipicephalus sanguineus Rocky Mountain Spotted Fever (Rickettsia rickettsiae) nationwide 6
Dermacentor variabilis Tularemia (Francisella tularensis) Rocky Mountain Spotted Fever (Rickettsia rickettsiae) Dermacentor andersoni Tularemia (Francisella tularensis) Rocky Mountain Spotted Fever (Rickettsia rickettsiae) Colorado Tick Fever (Colorado tick fever virus) 83 cases reported 2002 2012 7
Amblyomma americanum Bourbon virus? Heartland virus Ehrlichiosis (Ehrlichia chaffeensis Ehrlichia ewingii) Tularemia (Francisella tularensis) STARI Amblyomma maculatum Rickettsia parkerii rickettsiosis 8
Ixodes scapularis Ehrlichiosis (Ehrlichia muris eauclairensis) Lyme disease (Borrelia burgdorferi AND Borrelia mayonii) Anaplasmosis (Anaplasma phagocytophilum) Powassan virus Disease (Lineage II: deer tick virus) Babesiosis (Babesia spp.) Borrelia miyamotoi borreliosis Ixodes pacificus Borrelia miyamotoi borreliosis Lyme disease (Borrelia burgdorferi) Babesiosis (Babesia duncani) Anaplasmosis (Anaplasma phagocytophilum) http://www.cdc.gov/ticks/geographic_distribution.html 9
More Trouble: Increased disease incidence and expanded tick ranges 10
Laboratory Detection of Tick-borne Diseases Direct and indirect methods Direct detects the organism, it s antigens, or it s nucleic acid Commonly employ real-time PCR Blood smears are also commonly used for detection of Babesia species and morulae (bacterial clusters) of Anaplasma/Ehrlichia Indirect detects the host s immune response to the organism IgM and IgG-class antibodies The preferred test is dependent on time of infection Serology: IgM and IgG Patterns Titer/quantity IgM IgG 1 Infection 7 14 21 Days ~180 11
Direct Detection Methods General Pattern Titer/quantity Onset of symptoms DNA or RNA IgM IgG 1 Infection 7 14 21 Days ~180 12
For More Information Lyme Disease Part I Lyme Disease Part II New Hot Topics coming soon! Other Tick-Borne Diseases Neuroinvasive Lyme disease https://news.mayomedicallaboratories.com/ticks/ 13
Questions or requests Email to: MMLHotTopics@mayo.edu For more information Visit MayoMedicalLaboratories.com or call Mayo Laboratory Inquiry at 800-533-1710 14