Are deer the host that allows the ticks to become so abundant?
White-footed mice are a much more significant part of the tick life cycle because they become infected with Lyme disease and therefore allow the causative organism to remain viable. Over 90% of ticks feeding on wild mice become infected with the Lyme bacterium (PLoS Medicine June 6, 2006). Deer do not become infected with Lyme disease. Risk of exposure to Lyme disease correlates most closely with the number of the small mammal hosts that the immature tick stages feed upon, and with variations in the food sources for these mammals. A recent study done in various communities all over CT found no correlation between deer numbers and incidence of human Lyme disease. (Sources: Unpublished data from Yale University. Incompetence of deer as reservoirs of the Lyme disease spirochete, Telford SR 3rd, Mather TN, Moore SI, Wilson ML, Spielman A. Department of Tropical Public Health, Harvard School of Public Health, Boston, Massachusetts 02115.