It wasn’t: the bacteria, their genetic analysis showed, has been on North America for at least 60,000 years.The arrival of Europeans triggered a chain of events that unlocked its infection potential.
scapularis and others are heading toward the poles, especially in the northern hemisphere, where it’s estimated ticks’ range increases 28 miles a year.
The EPA, Pfeiffer notes, tracks a list of indicators of climate change in the U. It includes several factors you’d anticipate — growing-season length, wildfires, Great Lakes water levels — and the epidemiological bellwether of a warming globe: Lyme.
More broadly, the CDC found black-legged ticks in 30 percent of U. Impressively, ticks can spread several diseases with one bite.
Black-legged ticks cause not just Lyme but infectious diseases like anaplasmosis, ehrlichiosis, babesiosis, and Powassan encephalitis, which the epidemiologist Durland Fish believes might surpass Lyme in terms of its public health implications: Powassan leads to permanent brain damage in half of cases, and fatality in a tenth of infected people.
Some dystopian visions of the future revolve around humanoid robots or superviruses run amok; ticks and the diseases they spread are less cinematic but, still, a coproduction of humanity and nonhuman nature that is careering out of control.
Quiet, malign, slow-moving: ticks are the grotesques of the Anthropocene — emblematic of the way changes in the climate will infiltrate our lives almost without notice at first, attach themselves there, and wreak havoc over time.The threat of Lyme disease grows greater every year, as spring relaxes into summer and parasites the size of poppy seeds crawl in search of blood.Spread primarily by Ixodes scapularis — the black-legged tick, aka the deer tick — Lyme is now the most commonvector-borne illness in the United States.Spring arrives early and winter late; freezes are fewer and softer; temperatures in many places are warmer than usual — or, rather, the new normal is a few degrees above the old.This is all great news for Ixodes et al, and like many of the weird and once unforeseen eventualities of the climate age, it’s a crisis humans all but engineered.Eventually I noticed, at various times of day, phantom crawling sensations on different parts of my body, where I was sure I’d find a tick. The difference between me and the dog is that she takes a monthly prophylactic pill against ticks, and even has the option of a canine Lyme vaccine, whereas I don’t.A human version of the vaccine, Lymerix, was approved by the FDA in 1998 and briefly available for sale, before being pulled from the market in 2002.You can drag corduroy across the forest floor to collect ticks or you can simply walk through the woods with your best friend at your heel; this will accomplish, as any dog owner can attest, only slightly less robust results.I spent the last couple of summers in mountainous Tennessee, where ticks were plentiful; they found both the dog and me.Shrunken land has more exposure around its edges; sunlight on the perimeter promotes plant growth that shelters ticks.And the removal of predators like foxes and wolves has encouraged the growth of populations of white-tailed deer, which host and transport ticks, and white-footed mice, which serve as reservoirs for the bacteria — two species that tend to flourish near humans.