Comer K M
Companion Animal Medical Clinic, Puyallup, WA 98373.
Vet Clin North Am Small Anim Pract. 1991 Jan;21(1):27-44. doi: 10.1016/s0195-5616(91)50002-4.
Rocky Mountain spotted fever is an endemic tickborne disease found throughout the United States and other regions of the world. Exposure may result in a spectrum of disease from subclinical infection to severe or fatal multiorgan collapse. The disease is maintained in nature in Ixodid tick vectors and their hosts. The most important ticks in the United States are Dermacentor variabilis and Dermacentor andersoni. Small mammals are the natural reservoirs in the wild. Dogs become infected when a tick harboring Rickettsia rickettsii feeds on the dog. Dogs do not develop sufficient rickettsemia to act as a reservoir in the transmission of Rickettsia rickettsii. Thus, although dogs act as sentinels to the presence of the disease, they cannot directly transmit infection. Signs in early stages of disease often are nonspecific. The most characteristic laboratory abnormality is thrombocytopenia, but serologic testing is necessary for confirmation of infection. Tetracycline and chloramphenicol are effective antibiotics to treat infection. Treatment should continue for 14 to 21 days to allow host immune defenses to develop and eradicate the organism. Prevention requires avoidance of tick-infested areas and rapid removal of ticks should exposure occur.
落基山斑疹热是一种在美国及世界其他地区流行的蜱传疾病。接触该疾病可能导致一系列病症，从亚临床感染到严重或致命的多器官衰竭。这种疾病在自然界中通过硬蜱媒介及其宿主得以传播。美国最重要的蜱类是变异革蜱和安氏革蜱。小型哺乳动物是野外的自然宿主。当携带立氏立克次体的蜱叮咬狗时，狗就会被感染。狗不会产生足够的立克次体血症来成为立氏立克次体传播的宿主。因此，尽管狗可作为该疾病存在的哨兵，但它们不能直接传播感染。疾病早期的症状通常不具有特异性。最典型的实验室异常是血小板减少，但确诊感染需要进行血清学检测。四环素和氯霉素是治疗感染的有效抗生素。治疗应持续14至21天，以使宿主免疫防御系统得以发育并根除病原体。预防措施包括避免前往蜱虫滋生的地区，一旦接触蜱虫应迅速将其清除。
