Recent Surveillance Data
In 2019, a total of 34,945 confirmed and probable cases of Lyme disease were reported to CDC, about 4% more than in 2018. The geographic distribution of areas with a high incidence of Lyme disease appears to be expanding based on data reported to National Notifiable Disease Surveillance System (NNDSS). The number of counties with an incidence of ≥10 confirmed cases per 100,000 persons increased from 324 in 2008 to 432 in 2019. Due to the coronavirus disease 2019 (COVID-19) pandemic, data from some jurisdictions may be incomplete.