Surveillance data from 2011-2020 indicate a lower risk of Lyme disease in the USA in even-numbered years

Abstract

From 2011-2020 the number of reported cases of Lyme disease in the USA was lower in each even-numbered year compared with the preceding odd-numbered year. This observation suggests that fewer nymphal stage Ixodes scapularis ticks infected with Borrelia burgdorferi were present during even-numbered years in locations where people spend time.

Keywords: Babesia microti; Borrelia burgdorferi; Ixodes scapularis; Infection risk; Tick-borne infection.