Rickettsioses, spotted fever group

Rickettsioses, spotted fever group vary in severity; in incidence of the rash; in characteristics of the rash (maculopapular/vesicular/petechial); in incidence of eschars; in incidence of regional lymphadenopathy; in frequency of painful lymphadenitis; and in incidence of lymphangitis.

CASES/YEAR
25,000 (US); 400,000 (Global)
CATEGORY
AGENT TYPE
Rickettsiae
OTHER NAMES
Tickborne lymphadenopathy (R. slovaca); Lymphangitis-associated rickettsiosis (R. sibirica mongolotimonae); North Asian tick typhus (R. sibirica); Maculatum infection (R. parkeri); Australian sp. fever (R. marmionii); Japanese sp. fever (R. japonica); Flinders Island sp. fever (R. honei); Far Eastern sp. fever (R. heilongiangensis); Queensland tick typhus (R. australis);
ACUITY
Acute-Moderate
INCUBATION
2-21 days; [CCDM]
INITIAL SYMPTOMS
See "Rocky mountain spotted fever," Boutonneuse fever," and "African tick bite fever" covered separately; The classic initial symptoms of the spotted fever group (SFG) rickettsioses are fever, headache, and myalgia. [ABX Guide: Rickettsia species]
PRECAUTIONS
Standard
COMMENTS
The other SFG rickettsioses form a spectrum of varying clinical findings: in severity (from nonfatal to occasionally life-threatening); in incidence of the rash (from only half to almost all); in characteristics of the rash (from maculopapular to vesicular and from never petechial to frequently petechial); in incidence of eschars; in incidence of regional lymphadenopathy; in frequency of painful lymphadenitis (from never to frequently); and in incidence of lymphangitis (from never to almost half). [PPID, p. 2355] Common in rickettsioses: elevated transaminases, thrombocytopenia, leukopenia & leukocytosis; [ABX Guide: Rickettsia species] Anemia is common. [Cohen, p. 1667] The rash of rickettsial infections can involve the palms and soles in the later stages of infection. [PPID, p. 813] Rickettsia species can cause conjunctivitis. [Guerrant, p. 1004] Fatality rates without treatment: Rocky Mountain (20-25%), Boutonneuse (1-2.5%), African (none), Japanese (none), Queensland (2 fatal cases), Flinders Island (none), North Asian (none), Far Eastern (none), and Tickborne lymphadenopathy (none); [Cohen, p. 1667t]

Tickborne lymphadenopathy (R. slovaca);
Mild illness; Skin ulcer and erythema often of scalp with cervical lymphadenopathy; [CCDM, p. 516] Less than 1/2 of patients have fever, and rash is rare. Some patients have alopecia at the eschar site, and prolonged fatigue has been reported. [PPID, p. 2356]
Incubation: 2-7 days;
Reservoir: lagomorphs and rodents;
Occurrence: Europe and Asia;

Lymphangitis-associated rickettsiosis (R. sibirica mongolotimonae);
Rope-like lymphangitis from eschar to regional lymph nodes; [Guerrant, p. 327]
Incubation: 3-7 days;
Reservoir: rodents;
Occurrence: Southern France, Portugal, china, Africa;; [CDC Travel, p. 328]

North Asian tick typhus (R. sibirica);
Similar to Boutonneuse; Lymphadenitis is common.
Incubation: 3-7 days;
Reservoir: See RMSF; Ticks infest wild rodents;
Occurrence: North China, Mongolia and Asiatic Russia;

Maculatum infection (R. parkeri);
Mild illness similar to African tick fever; May have eschar and maculopapular or vesicular rash;
Incubation: 2-10 days;
Reservoir: rodents;
Occurrence: Coast southeastern USA; southern South America (Argentina, Uruguay, and Brazil)

Japanese spotted fever (R. japonica);
Fever, eschar, maculopapular rash, lymphadenopathy; Some fatalities reported; [CCDM, p. 516] 100% have rash and fever; 90% have eschar; Complications include meningoencephalitis, ARDS, and shock; [PPID, p. 2355]
Incubation: 3-7 days;
Reservoir: rodents and reptiles;
Occurrence: Japan;

Flinders Island spotted fever (R. honei);
Mild illness; Maculopapular rash; Eschar and lymphadenopathy are rare;
Incubation: 3-7 days;
Suspected reservoirs are reptiles, migratory birds, and rodents;
Occurrence: Australia, Thailand, Flinders Island, Tasmania;

Far Eastern spotted fever (R. heilongiangensis);
Fever, eschar, slight macular or maculopapular rash, lymphadenopathy, and lymphangitis; [CCDM, p. 516] Some patients have rope-like lymphangitis; [PPID, p. 2355]
Incubation: 3-7 days;
Reservoir: rodents and lagomorphs;
Occurrence: Far east Russia and northern China

Queensland tick typhus (R. australis);
Similar to Boutonneuse; Rash can be vesicular;
Incubation: 7-10 days;
Reservoir: See RMSF; Ticks infest marsupials and wild rodents;
Occurrence: Queensland, New South Wales, Tasmania and coastal areas of eastern Victoria, Australia;
[CCDM, p. 514-20; CDC Travel, p. 325-28; Guerrant, p. 323-8]
DIAGNOSTIC
Serology (indirect immunofluorescence); Skin biopsy (direct immunofluorescence); PCR; Contact state health department or CDC Division of Viral and Rickettsial Diseases (404-639-1075); [ABX Guide: Rickettsia species]
SCOPE
See "Comments."
SIGNS & SYMPTOMS
  • >fatigue, weakness
  • >fever
  • >myalgia
  • G liver function test, abnormal
  • H anemia
  • H leukocytosis
  • H leukopenia
  • H lymphadenopathy
  • H thrombocytopenia
  • N headache
  • O conjunctivitis, acute
  • S entry wound with lymph nodes
  • S lymphadenitis, acute
  • S nodular lymphangitis
  • S papules or plaques
  • S petechiae and ecchymoses
  • S rash (exanthem)
  • S rash on palms
  • S skin blister or vesicles
  • S ulcer of skin
  • *ARDS
  • *encephalitis
  • *meningitis
  • *shock
ANTIMICROBIC

Yes

VACCINE

No

ENTRY
VECTOR
Ticks
RESERVOIR
Cattle, Goats and Sheep, Dogs, Rabbits, Rodents, Wild Animals
RISK FACTORS
  • Travel to endemic area
  • Work or play in tick-infested area
REFERENCES FOR CASES/YEAR
1. (US) Guesstimate: Assume Maculatum infection cases/yr is 1/2 that of RMSF;
2. (Global) Guesstimate: Assume each of 8 diseases has rate similar to RMSF; 8 X 50,000 = 400,000;