Wisconsin Division of Public Health Disease Surveillance Manual (EpiNet, February 2005)

I . IDENTIFICATION

A. CLINICAL DESCRIPTION: A tick-borne illness caused by Rickettsia rickettsii characterized by fever, myalgia, headache, and petechial rash (frequently on the palms and soles).

B. REPORTING CRITERIA: Clinical diagnosis with laboratory confirmation.

C. LABORATORY CRITERIA FOR CONFIRMATION:

• A fourfold change in antibody titer to Rickettsia rickettsii antigen by IFA, CF, latex agglutination, microagglutination, or indirect hemagglutination antibody test in two serum samples, OR
• A positive PCR assay, OR
• Immunostaining of antigen in a skin biopsy or autopsy sample, OR
• Isolation and culture of R. rickettsii from a clinical specimen.

D. WISCONSIN CASE DEFINITION:

1. Confirmed RMSF: A clinically compatible illness that is laboratory confirmed (see above).

2. Probable RMSF: A clinically compatible illness with a single positive antibody titer by IFA ( ³ 1:64 if IgG); OR a single CF titer ³ 1:16 ; OR a single titer ³ 1:128 by a latex agglutination, indirect hemagglutination antibody, or microagglutination test; OR a fourfold rise in titer or a single titer >1:320, by Proteus OX-19 or OX-2 test.

II. ACTIONS REQUIRED / PREVENTION MEASURES

A. WISCONSIN DISEASE SURVEILLANCE CATEGORY II: Report to the patient's local health officer on an Acute and Communicable Disease Case Report (DPH 4151) or other means within 72 hours of the identification of a case or suspected case.

B. EPIDEMIOLOGY REPORTS REQUESTED:

• Acute and Communicable Diseases Case Report (DPH 4151)
• Tick-borne Rickettsial Disease Case Report (CDC 55.1)

C. PUBLIC HEALTH INTERVENTIONS:

Obtain travel history for the month preceding onset of symptoms to determine site of probable exposure.

Patient education as needed to minimize future tick exposure.

III. CONTACTS FOR CONSULTATION

A. BCDP / COMMUNICABLE DISEASE EPIDEMIOLOGY SECTION: (608) 267-7321

B. REGIONAL STAFF: See Epinet Introduction: “REGIONAL OFFICE CONTACTS”.

C. WSLH / VIRAL AND RICKETTSIAL SEROLOGY: (608) 262-0248.

IV. RELATED REFERENCES

1. “Rocky Mountain Spotted Fever” DPH Disease Fact Sheet Series: View a list of all current Communicable Disease Fact Sheets

2. Heymann DL, ed. LEGIONELLOSIS. Control of Communicable Diseases Manual. 18 th ed. Washington , DC : American Public Health Association, 2004:292-295.

3. Pickering LK, ed. Rocky Mountain Spotted Fever. In: Red Book: 2003 Report of the Committee on Infectious Diseases. 26 th ed. Elk Grove Village , IL : American Academy of Pediatrics, 2003:532-534.

V. DISEASE TRENDS

There was one reported case of Rocky Mountain Spotted Fever in Wisconsin between 1999 and 2003.