Unité de Recherche en Maladies Infectieuses et Tropicales Emergentes (URMITE), UMR CNRS-IRD 6236.
Curr Infect Dis Rep. 2009 Jan;11(1):40-50. doi: 10.1007/s11908-009-0007-5.
During most of the 20th century, Rickettsia rickettsii, the agent of Rocky Mountain spotted fever, was considered the only tick-borne rickettsia associated with human diseases in the Americas. This dogma suggested that the other characterized and noncharacterized rickettsiae isolated from ticks were not pathogenic to humans. This concept has been modified extensively in the past 10 years with the identification of at least three additional rickettsial species that cause human tick-borne rickettsioses and that are prevalent in the Americas, including Rickettsia parkeri, Rickettsia massiliae, and Rickettsia africae. Moreover, the genetic variability of R. rickettsii and the milder forms of Rocky Mountain spotted fever reactivate the hypothesis that some circulating genotypes of R. rickettsii may be more virulent than others and may explain the wide variations in fatality rates of the disease.
在 20 世纪的大部分时间里，落矶山斑点热的病原体——立克次体立克次体（Rickettsia rickettsii）被认为是美洲唯一与人类疾病有关的蜱传立克次体。这一教条表明，从蜱虫中分离出的其他特征明确和不明确的立克次体对人类没有致病性。这一概念在过去 10 年中得到了广泛修正，因为已经确定了至少另外三种导致人类蜱传立克次体病的立克次体物种，这些物种在美洲很普遍，包括帕克立克次体（Rickettsia parkeri）、马赛立克次体（Rickettsia massiliae）和非洲立克次体（Rickettsia africae）。此外，立克次体立克次体的遗传变异性和落矶山斑点热的较轻形式重新激活了这样一种假设，即循环的某些基因型可能比其他基因型更具毒性，这可以解释该病死亡率的巨大差异。
