Are Ticks and Tick-Borne Diseases Spreading due to Global Warming?

 

If you love the outdoors as much as I do, you may become a bit concerned about the latest news on ticks and tick-borne diseases. According to recent studies, global warming is contributing to both the spread northward of tick habitat and the amount of time annually during which ticks can feed. Warmer winters in northern regions are allowing ticks to survive longer, travel farther, and emerge from dormancy three weeks earlier in the spring, says research on blacklegged ticks spanning 19 years. Unfortunately, along with the spread of the ticks themselves comes the accompanying spread of their numerous diseases, the worst of which remains the incurable Lyme Disease.

The change in seasonal tick re-emergence should warrant a moving up of the official Lyme Disease Awareness Month from May to April, says Richard Ostfeld, a Cary Institute of Ecosystem Studies disease ecologist. According to Ostfield, “The nymphs (immature ticks which are most likely to transmit disease) used to peak in June. Now it’s happening in mid-May, and if you project forward with simple climate models, it’ll be early May within a couple of decades.” Ostfield’s paper, published in a publication of the British Royal Society, the journal Philosophical Transactions B, tied tick emergence directly to climate change.

According to the Centers for Disease Control and Prevention, the number of Lyme disease cases confirmed in the United States has been steadily increasing from 11,700 confirmed cases in 1995 to 27,203 in 2013. This increase is clearly correlated to spreading tick populations, say researchers. “The reason we have an increasing incidence of Lyme disease every year is because tick populations are expanding and exposing more people to tick bites,” says Durland Fish, Professor of Epidemiology at the Yale School of Public Health. One of the first to study and co-author research on climate change and Lyme disease, Fish explains that while the blacklegged ticks studied are predicted to increase by up to 213 percent in Canada by the year 2080, they will likely also subsequently shrink in habitat range in the much warmer areas of the southern United States.

With Lyme disease being most commonly reported in 14 states (95 percent) of the Northeast, Upper Midwest, and Mid-Atlantic regions of the country, it’s encouraged that citizens and visitors to those areas take precautions to avoid and repel ticks, learn about removing a tick, and understand how to recognize common symptoms of tick-borne diseases. It’s also interesting and worthwhile to learn about the way ticks seek out hosts and how they actually spread disease on a host is obtained. Any awareness increased is undoubtedly helpful as we learn to face the unpredictable and multi-faceted changes being made by global warming.