NOTE: A surveillance case definition is a set of uniform criteria used to define a disease for public health surveillance. Surveillance case definitions enable public health officials to classify and count cases consistently across reporting jurisdictions. Surveillance case definitions are not intended to be used by healthcare providers for making a clinical diagnosis or determining how to meet an individual patient’s health needs.
CSTE Position Statement(s)
Clinical DescriptionA tickborne febrile illness most commonly characterized by acute onset and usually accompanied by myalgia, headache, and petechial rash (on the palms and soles in two thirds of the cases)
Laboratory Criteria For Diagnosis
- Fourfold or greater rise in antibody titer to Rickettsia rickettsii antigen by immunofluorescence antibody (IFA), complement fixation (CF), latex agglutination (LA), microagglutination (MA), or indirect hemagglutination antibody (IHA) test in acute- and convalescent-phase specimens ideally taken greater than or equal to 3 weeks apart, OR
- Positive polymerase chain reaction assay to R. rickettsii, OR
- Demonstration of positive immunofluorescence of skin lesion (biopsy) or organ tissue (autopsy), OR
- Isolation of R. rickettsii from clinical specimen