A forty-year review of Rocky Mountain spotted fever cases in California shows clinical and epidemiologic changes
Table 2
Incidence of RMSF cases per million persons by ethnicity, using ethnicity-specific population estimates, 1980–2019.
The Incidence rate ratio compares the ethnicity specific incidence between 2000–2019 (numerator) and 1980–1999 (denominator) and is a measure of excess risk between the two reporting blocks.