In this study, variability in reported
Lyme disease incidence between 1993 and 2001 was analyzed in seven states in the northeastern part of the USA. Positive significant correlations at p < 0.05 were found in all states between early summer
disease incidence and the June moisture index in the region two years prior. These correlations may reflect an enhanced nymphal Ixodes scapularis survival under wetter conditions. In some states, significant correlations were observed related to warmer winter weather a year and a half prior to
disease incidence, which may have been due to higher survival and activity levels of the white-footed mouse, an important host for I. scapularis ticks.