IT STARTED WITH vomiting and a fever. But a few days later, five-month-old Liam was in the emergency room, his tiny body gripped by hourly waves of seizures. X-rays and MRIs showed deep swelling in his brain. When an infectious disease specialist at Connecticut Children’s Medical Center diagnosed Liam with Powassan virus in November, he became the first recorded case in state history. Doctors think Liam picked up the rare neurological disease from a tick his father brought back after a deer hunting trip.
The toddler survived with some scar tissue—but not everyone who gets Powassan, POW for short, is so lucky. With no treatment available, half of all people who contract the virus suffer permanent brain damage; 10 percent die. And while POW is nowhere near as prevalent as that other tick-borne summer scourge—Lyme—it is starting to show up more often.
Scientists disagree if that’s because doctor awareness and improved testing tools are just turning up more cases, or whether anthropogenic forces like climate change, reforestation, and suburban developments are driving up the likelihood that humans will come in contact with POW. But one thing’s for sure: The only way to get those answers is to collect more data. Entomologists and virologists have been saying this for years. Yet current surveillance efforts are limited to counting cases only once they’ve reached hospital beds.
A Taste for Flesh
As far as emerging diseases go, Connecticut has had more than its fair share. Liam lives in the town of Griswold, just 30 miles down the road from Lyme, where in 1975 a mysterious outbreak of swollen knees, skin rashes, headaches, and severe fatigue swept through the town. Lyme disease has reached epidemic proportions in recent years; cases have tripled in the US over the last two decades as the tick that spreads the illness has expanded its territories from a few northern pockets into half of all US counties.
At some point along its manifest destiny tour, Ixodes scapularis, the blacklegged, or deer tick, seems to have picked up POW. Maybe it was in a skunk burrow or a badger den—historically, POW is carried around by a different kind of tick that prefers members of the weasel family. And unlike their weasel-loving brethren, deer ticks, in addition to their namesake host, have a real taste for human flesh.