A New York disease ecologist is sounding the alarm bells for the Northeastern United States as he is warning of a swell of Lyme disease cases this spring according to a Friday news release.
Dr. Richard Ostfeld, an ecologist at the Cary Institute of Ecosystem Studies in Millbrook, NY says this surge in the bacterial infection will be due to decreasing acorn crops and white-footed mice populations.
He explains this acorn-mice phenomenon saying, “We had a boom in acorns, followed by a boom in mice. And now, on the heels of one of the smallest acorn crops we’ve ever seen, the mouse population is crashing. This spring, there will be a lot of Borrelia burgdorferi-infected black-legged ticks in our forests looking for a blood meal. And instead of finding a white-footed mouse, they are going to find other mammals—like us.”
Acorn crops, like other crops, vary from year-to-year, so in a lull year it will affect the mouse winter survival and breeding decreasing the population of this rodent.
Ecologists at Cary have been looking at this connection for some time:
In 2010, acorn crops were the heaviest recorded at their Millbrook-based research site. And in 2011, mouse populations followed suit, peaking in the summer months. The scarcity of acorns in the fall of 2011 set up a perfect storm for human Lyme disease risk.
The larval stage of the ticks that feed on the boom of mice in last year will be looking for a blood meal in their nymphal stage, the stage where the tick is well suited to transmitting Borrelia burgdorferi, the bacterium that causes Lyme.
Contrary to popular belief, a mild winter like we are presently experiencing does not cause an increase in ticks according to Dr. Ostfeld, but it can bring adult tick out of dormancy early.
Lyme disease is tick borne, bacterial infection that is relatively common in the United States. Ixodes scapularis is the vector for Lyme disease in the Northeast. In addition it is also the vector for human granulocytic anaplasmosis and babesiosis. Because of this, co-infections with multiple diseases are seen.
First discovered in 1975 in a town in Connecticut where it derives its name, Lyme disease is caused by the spirochete, Borrelia burgdorferi (Bb). It is the most prevalent vector-borne illness in the U.S., with the majority of cases occurring in the Northeast.
The disease is characterized by a distinctive skin lesion known as erythema migrans (EM) and possibly systemic, chronic symptoms including neurological, rheumatologic and cardiac involvement over time (months to years). Some reports say that the optic nerve may also be affected.
The EM which is the first manifestation in the majority of cases is a red papule that expands slowly frequently showing a clear center (bull’s eye). They may be seen singly or in multiples.
With or without EM, other early symptoms may include malaise, fatigue, fever, headache and stiff neck. Body aches and migratory joint pain may also be seen.