Robinson D, Leo N, Prociv P, Barker S C
Department of Microbiology and Parasitology, and Institute for Molecular Biosciences, University of Queensland, 4072 Brisbane, Australia.
Parasitol Res. 2003 Jun;90(3):209-11. doi: 10.1007/s00436-003-0842-5. Epub 2003 Feb 27.
Since the pioneering work of Charles Nicolle in 1909 [see Gross (1996) Proc Natl Acad Sci USA 93:10539-10540] most medical officers and scientists have assumed that body lice are the sole vectors of Rickettsia prowazekii, the aetiological agent of louse-borne epidemic typhus (LBET). Here we review the evidence for the axiom that head lice are not involved in epidemics of LBET. Laboratory experiments demonstrate the ability of head lice to transmit R. prowazekii, but evidence for this in the field has not been reported. However, the assumption that head lice do not transmit R. prowazekii has meant that head lice have not been examined for R. prowazekii during epidemics of LBET. The strong association between obvious (high) infestations of body lice and LBET has contributed to this perception, but this association does not preclude head lice as vectors of R. prowazekii. Indeed, where the prevalence and intensity of body louse infections may be high (e.g. during epidemics of LBET), the prevalence and intensity of head louse infestations is generally high as well. This review of the epidemiology of head louse and body louse infestations, and of LBET, indicates that head lice are potential vectors of R. prowazekii in the field. Simple observations in the field would reveal whether or not head lice are natural vectors of this major human pathogen.
自1909年查尔斯·尼科勒的开创性工作以来[见格罗斯(1996年)《美国国家科学院院刊》93:10539 - 10540],大多数医务人员和科学家都认为体虱是普氏立克次体的唯一传播媒介,普氏立克次体是虱传流行性斑疹伤寒(LBET)的病原体。在此,我们回顾关于头虱不参与LBET流行这一公理的证据。实验室实验证明了头虱传播普氏立克次体的能力,但尚未有该现象在野外的相关报道。然而,认为头虱不传播普氏立克次体的假设意味着在LBET流行期间未对头虱进行普氏立克次体检测。体虱明显(高度)感染与LBET之间的紧密关联促成了这种认知,但这种关联并不排除头虱作为普氏立克次体传播媒介的可能性。实际上,在体虱感染的流行率和感染强度可能较高的地方(如在LBET流行期间),头虱感染的流行率和感染强度通常也较高。对头虱和体虱感染的流行病学以及LBET的综述表明,头虱在野外是普氏立克次体的潜在传播媒介。在野外进行简单观察就能揭示头虱是否是这种主要人类病原体的自然传播媒介。