Mice drive Lyme disease tick risk

A long-term study by the Cary Institute of Ecosystem Studies, published in the Proceedings of the National Academy of Sciences of the United States of America, challenges the assumption that deer are the main driver of Lyme disease risk. Analyzing 30 years of data from a New York forest, researchers found that white-footed mice, not white-tailed deer, are closely linked to the number of young blacklegged ticks, the life stage most likely to infect humans. A year with a large mouse population was followed by about a 40% increase in nymphal ticks the following year. However, more mice do not necessarily mean a higher percentage of ticks carrying Lyme bacteria, because other animals like skunks, squirrels, and opossums also feed larval ticks and are less efficient at transmitting the bacteria. Large acorn crops can trigger a chain reaction: more acorns mean more food for mice, leading to more ticks two years later. The study also found that extreme temperatures do not necessarily kill blacklegged ticks, as they can shelter in soil and leaf litter. The findings come as tick-borne diseases are a growing public health concern, with Lyme disease affecting nearly half a million people annually in the United States. Separately, the article discusses the spread of lone star ticks and alpha-gal syndrome, with several states, including United States — Massachusetts State Police, United States — Missouri, United States — Oklahoma City, and United States — Ohio, taking steps to make alpha-gal syndrome a reportable disease.