The New York Times Trilobites column has an interesting article about ticks.  A new paper in the journal Current Biology, looked at how ticks are attracted to their hosts.  It seems that static electric fields, which are produced naturally by animals (including humans) might be helping ticks to extend their reach from the surrounding vegetation onto their next potential meal. Hopefully, this new discovery will spur the development of new materials that repel their advances.

Many a tick researcher has had to chase down an errant arachnid after it was flung about by static from plastic or nylon equipment because of static, said Sukanya Narasimhan, a biologist at Yale University who was not involved with the new study. But popping ticks were considered nothing more than a nuisance; “we’ve never given it much thought,” Dr. Narasimhan said.

To better understand what was happening, Dr. England and Dr. Lihou brought their ticks into a tightly controlled environment that attempted to mimic conditions they face when questing for a blood meal.

When a tick looks to feed, it stands atop a plant that is grounded, which means its electrical charge is dissipating down into the earth. To simulate this condition, the ticks were placed on a grounding plate. The researchers then passed an electrode, was charged to 750 volts, three millimeters over the ticks. This voltage is similar to or even lower than that of a typical mammal’s electric field. The ticks were invariably pulled upward against gravity onto the electrode. Holding the parasites close to a similarly charged rabbit’s foot produced the same flying tick phenomenon.

To get a sense of what this animal attraction might mean for a potential tick host in nature, Dr. England designed a computer model of the electrical field around a cow.