Table 1.
Variable effects of Rickettsia observed in different host animals.
| Rickettsia species, isolate | Associated tick species | Animal species | Observed effects in the source animal | Records of isolations (source) | Reference |
|---|---|---|---|---|---|
| R. rickettsii, Microtus agent B14009a | D. variabilisb | Meadow mouse, Microtus pennsylvanicus | None (apparently healthy) | Yes (brain, spleen, and liver) | (26) |
| R. rickettsii, Mp23, Mp40, Pit1 | D. variabilisb | Wild mice, Peromyscus leucopus, Pitymys pinetorum | Tissue persistence; seroconversion | Yes (liver and spleen) | (27) |
| R. rickettsii, Di6 | D. variabilisb | Opossum, Didelphis marsupials virginiana | Tissue persistence; low level seroconversion | Yes (liver and spleen) | (27) |
| R. rickettsii, Rab1 | D. variabilisb | Eastern cottontail rabbit, Sylvagus floridans | Tissue persistence; seroconversion | Yes (liver and spleen) | (27, 28) |
| R. rickettsii, Si7 | D. variabilisb | Cotton rat, Sigmodon hispidus | Tissue persistence; low level seroconversion | Yes (liver and spleen) | (27) |
| R. rickettsii, Sheila Smith | N/A | Cotton rat, Sigmodon hispidus | Tissue persistence; short-term rickettsiemia; low level seroconversion | Yes (blood)b | (29) |
| R. rickettsii, Sawtooth | D. andersoni | Snowshoe hare, Lepus americanus | Rickettsiemia (exp) | Yes (xenodiagnosis) | (22, 30) |
| R. rickettsii, Sawtooth | D. andersoni | Golden-mantled ground squirrel, Citellus lateralis tescorum | Rickettsiemia (exp) | Yes (xenodiagnosis) | (22, 30) |
| R. rickettsii, Sawtooth | D. andersoni | Chipmunks, Eutamias amoenus | Rickettsiemia (exp) | Not reported | (22, 30) |
| R. rickettsii, Sawtooth | D. andersoni | Columbian ground squirrel, Urocitellus columbianus | Rickettsiemia (exp) | Yes (xenodiagnosis) | (22, 30) |
| R. rickettsii, Sawtooth | D. andersoni | Meadow mice, Microtus spp. | Rickettsiemia (exp) | Yes (xenodiagnosis) | (22, 30) |
| R. rickettsii, Sawtooth | D. andersoni | Bushy-tailed woodrat, Neotoma cinerea | Seroconversion | No | (22, 30) |
| R. rickettsii, Taiaçu | A. cajennense | Capybara, Hydrochoreus hydrochaeris | Seroconversion; rickettsiemia (exp) afebrile | Yes (xenodiagnosis) | (31) |
| R. rickettsii, ITU | A. cajennense | Capybara, Hydrochoreus hydrochaeris | Seroconversion | No | (32) |
| R. rickettsii, Taiaçu | A. cajennense | Opossum, Didelphis aurita | Rickettsiemia (exp) asymptomatic; no macro or micro pathological abnormalities | Yes (xenodiagnosis) | (33) |
| R. rickettsii, Taiaçu | Rh. sanguineus | Dog, Canis familiaris | Rickettsiemia (exp) | Yes (xenodiagnosis) | (34) |
| R. rickettsii, Sawtooth | Rh. sanguineus (presumably North America) | Dog, Canis familiaris | Rickettsiemia (exp); seroconversion | Yes (cell culture) | (35) |
| R. rickettsii, Wachsmuth | Rh. sanguineus (presumably North America) | Dog, Canis familiaris | Rickettsiemia (exp); seroconversion | Yes (xenodiagnoses) | (35) |
| R. rhipicephali, 3-7-♀6 | Rh. sanguineus (presumably North America) | Dog, Canis familiaris | Seroconversion | No | (35) |
| R. montanensis | Rh. sanguineus (presumably North America) | Dog, Canis familiaris | Seroconversion | Not tested | (35) |
| R. parkeri | A. maculatum | Cattle | Seroconversion | No | (36) |
| R. parkeri, Portsmouth | A. maculatum | Cotton rat, Sigmodon hispidus | Short-term rickettsiemia; seroconversion | Yes, re-isolation | (37) |
| R. parkeri, Portsmouth | A. maculatum | Northern bobwhite quail, Colinus virginianus | Seroconversion | No | (37) |
| R. conorii, Malish | Rh. sanguineus | Dog, Canis familiaris | Rickettsiemia (transient); febrile illness; seroconversion | Yes (xenodiagnoses) | (38, 39) |
| Hare, rabbit | Asymptomatic rickettsiemia; seroconversion | No | (40) |
aName of the isolate is based on the description found in the original publication, although the identification of this isolate as R. rickettsii is very presumptive based on the biological characteristics included in the publication (26). It may, in fact, be Rickettsia montanensis but the isolate is no longer available.
bTick species is indicated based on the known circulation of D. variabilis in the area where isolates were obtained.
exp., experimental animals under laboratory conditions.