BUG WEEK: Day 4- Tick talk (cont.)

Yesterday just about wore me out with all the tick stuff. But we shall press on...

Ixodes ticks also carry:
1. Ehrlichia-- no skin findings, presents as fever, HA, jt point, malaise... your classic fever of unknown origin
- the tick is the vector and the reservoir includes dogs, foxes, coyotes, deer, and rodents
- seen in the NE US
- infects macrophages, difficult to culture, but can possibly see microorganism in cells on blood smear

2. Babesia-- no skin findings, hemoprotozoan parasite (often confused with malaria), most infections are asymptomatic, but can produce fever, chills, sweating, myalgias, fatigue, hepatosplenomegaly, and hemolytic anemia after a 1 to 4 week incubation period
- the tick is the vector and reservoir
- seen in the NE and Midwest as well as CA and WA
- infects red blood cells, can be seen on blood smear

The soft tick Ornithodoros carries:
1. Borreliae hermsii-- no skin findings AND the tick falls off by itself, so most people don't know they had a bite at all
- presents a lot like Ehrlichiosis with recurring fevers
- western US


Hard ticks can also transmit...
1. ROCKY MOUNTAIN SPOTTED FEVER (Rickettsia rickettsii)--finally some skin findings!
- contrary to popular belief, it is most common in the Appalachians, but is seen in the Rocky Mountains, Central and South America
- can be very severe
- stages of disease: fever, malaise, muscle aches -> classic palms and soles rash -> systemic vasculitis
- the tick is the vector and rodents or dogs are the reservoir



The lone star tick (Amblyomma americanum) is pretty distinctive with that big colored dot on its back. It has one ill-defined disease association...
1. Southern Tick-Associated Rash Illness (STARI) (this one I didn't learn about in school, but found on the CDC's web page)-- skin findings again!
- it looks just like erythema migrans and can be easily confused for Lyme disease
- but the CDC says that the lone star tick does not carry Borrelia burgdorferi
- my lit search only came up with 3 articles on pubmed

Masters E, Granter S, Duray P, Cordes P. Physician-diagnosed erythema migrans and erythema migrans-like rashes following Lone Star tick bites.
Arch Dermatol. 1998 Aug;134(8):955-60.

- this one claims to have isolated B. burgdoferi in lone star ticks infesting the farm of a person with a tick bite and erythema migrans, so it looks like lone star ticks could transmit lyme disease. it also looks like no one cares to find out more since there is not much research on this topic
- these ticks are in the southeast and mid south


Finally, the last tick-borne illness...
The hard tick Hyalomma carries one virus...
1. Crimean-Congo Hemorrhagic Fever from the Nairovirus (of the Bunyavirus family)-- some skin findings!
- petechiae, flushing, jaundice can all be found (which kind of go with the hemorrhagic fever thing)
- the tick is both reservoir and vector
- most commonly found in Eastern Europe, particularly Russia (but also in China and India)
- it presents like a lot of the other diseases discussed today with high fever, joint pains, headache, and vomiting

That's all for the ticks!