Know your nymphs!

Three nymphs of blacklegged tick, Ixodes scapularis, three nymphs of lone star tick, Amblyomma americanum, and eight nymphs of the exotic longhorned tick, Haemaphysalis longicornis.

Source: https://fonseca-lab.com/category/research-projects/ticks-tick-borne-diseases/

Popular press article on factors underlying geographic variation in Lyme disease incidence

https://www.wiscontext.org/confounding-geography-lyme-disease-us

Larval engorgement photo-series

A time series of larval blacklegged tick engorgement.

Life stages of the blacklegged tick (Ixodes scapularis)

 Male and female - active from late fall through spring.

Nymphs - active in late spring through summer

 Larvae - active mid to late summer

Engorged female with egg mass laid in winter.  Eggs hatch mid-summer.

Female and male on a deer - only females become engorged.

"Dragging" to collect host-seeking ticks from vegetation

Lyme gradients in the Appalachians?

University of Tennessee MS student Janetta Kelly has joined the team, and will be comparing levels of Borrelia burgdorferi infection in blacklegged ticks along the eastern vs western foothills of the southern Appalachians.

Our first field trip to Manchester KY produced blacklegged ticks on all the transects we dragged.

Video clips of human-biting ticks from the eastern United States

These 720P 30fps video clips are downloadable from Vimeo in H.264 MP4 format.

American Dog Tick female (Dermacentor variabilis)  1:19 min

https://vimeo.com/223913243

American Dog Tick female (Dermacentor variabilis)  1:45 min

https://vimeo.com/224372258

American Dog Tick male (Dermacentor viariabilis) 3:15 min

https://vimeo.com/224373090

Blacklegged Tick female (Ixodes scapularis; "Deer Tick")  1:22 min

https://vimeo.com/152856969

Blacklegged Tick male (Ixodes scapularis; "Deer Tick")   1:46mm

https://vimeo.com/225437640

Blacklegged Tick nymphs (Ixodes scapularis; "Deer Tick")  0:34 min

https://vimeo.com/179964347

Blacklegged Tick larvae (Ixodes scapularis; "Deer Tick")  0:30 min

https://vimeo.com/184602687

Lone Star Tick female (Amblyomma americanum)  2:26 min

https://vimeo.com/225438138

Lone Star Tick male (Amblyomma americanum) 1:50 min

https://vimeo.com/225438669

Lone Star Tick nymph (Amblyomma americanum)  2:42 min

https://vimeo.com/229216974

Credit: Graham Hickling ghicklin@utk.edu
Center for Wildlife Health, University of Tennessee Knoxville

Images of human-biting ticks that are active in Tennessee in the Spring

 Female Dog tick (Dermacentor variabilis)

Female Dog tick (Dermacentor variabilis)

Male Dog tick (Dermacentor variabilis)

 Nymphal Lone Star tick  (Amblyomma americanum)

 Female Lone Star tick (Amblyomma americanum)

 Female Lone Star tick (Amblyomma americanum)

Male Lone Star tick (Amblyomma americanum)

Male Lone Star tick (Amblyomma americanum)

Powassan virus is not currently a significant risk in southern states

CNN has a recent article about Powassan virus, spread by blacklegged ticks: http://www.cnn.com/2017/05/03/health/powassan-tick-virus/index.html

Here's a map of the locations of Powassan cases in recent years.  While the article claims "everyone" is at risk, there is in fact currently no significant risk of this disease for folk in southern states.  I know of one report of a patient being treated for Powassan in TN, however I checked with the doctor involved, who says the child contracted the infection on Long Island NY.

Regional variation in tick-borne disease risk deserves more attention than it gets.

Reminder - nymphal blacklegged ticks are SMALL!

For those in Lyme-endemic areas, the risk in late spring through summer comes from the nymphal (teenage) life-stage of the blacklegged tick.   The media almost always uses images of the adult ticks in articles about tick-borne disease - be aware that the nymphs are much smaller!

Engorged blacklegged tick larvae waiting for spring, hidden under leaf litter

These tick larvae, photographed in mid-January in Tennessee, fed on mouse blood back in September. They spend the winter buried deep in the leaf litter, waiting for Spring and the opportunity to molt into host-seeking nymphs.