Geographic Distribution

Notes on tickborne disease surveillance data:

Cases are reported from the patient’s county of residence, not necessarily the place where they were infected by or exposed to ticks. Cases are not included in this list if county of residence was not reported.
Many high incidence states have modified surveillance practices that have led to notable decreases in case counts over time. Consequently, these data may not accurately represent disease trends in those areas.
Not all diseases are reportable from every jurisdiction in every year. For more information, see Annual Statistics from the National Notifiable Diseases Surveillance System (NNDSS) or contact your local health department.