Graduate student’s discovery can enable tick population management

Doctoral student Ann Carr is hard at work developing ways to attract ticks so that the general population can avoid them.

Under the direction of Department of Entomology professors Dr. Charles Apperson, Dr. Michael Roe and Dr. Coby Schal, Carr recently discovered that two chemicals – acetone and ammonium hydroxide – attract high numbers of the tick species Amblyomma americanum.

The development of this chemical cocktail could open new doors for the screening and management of tick populations in North Carolina and beyond.

Carr’s paper was featured as the editor’s choice in the March 2013 edition of the journal Medical and Veterinary Entomology, a publication of The Royal Entomological Society.

“We started out looking for attractants that were easier to use and less expensive than carbon dioxide,” said Carr, who earned her master’s degree in entomology from N.C. State in 2011. “We surveyed a whole slew of chemicals before we discovered that ammonium hydroxide and acetone are very effective at attracting ticks.”

After about a year of work in the lab, Carr took her findings out into the field, using the new attractant to collect ticks in the forest near Raleigh’s Shearon Harris nuclear power plant.

“It was amazing,” Carr said. “One tiny vial would attract 30 to 50 ticks in an hour.”

With this development, researchers will be able to collect higher numbers of ticks to monitor populations and migratory patterns, as well as screen them for diseases.

“We’re going back out into the woods to use our attractant with sticky traps – like the ones you buy for your home – to see if we can decrease the number of ticks in the area to the point that you could walk around without insect repellant and not get bitten,” Carr said.

If the sticky trap concept works, Carr said she’s hoping it eventually could be brought to market for consumer use.

Carr also worked with a team to sequence the genes inside a tick’s nose to better understand the insect’s olfactory process.

“How ticks smell is such an important part of their feeding behavior,” Carr said. “We just finished the sequence, and now we’re going through the data and pulling out proteins and receptors that will help us figure out what’s happening in there.”

After Carr earns her Ph.D. in entomology in 2014, the sky’s the limit.

She is considering all sorts of job possibilities, from international relief work to commercial product development.

“I actually wanted to go to vet school pretty much my whole life,” Carr said. “But after taking entomology classes to fill undergrad elective hours, I ended up loving them. I guess you could say I got stuck on ticks.”

— Suzanne Stanard