Thiaucourt F, Dedieu L, Maillard J C, Bonnet P, Lesnoff M, Laval G, Provost A
CIRAD-EMVT, Santé Animale, Montpellier, France (World Reference Laboratory for CBPP for the FAO).
Dev Biol (Basel). 2003;114:147-60.
Contagious bovine pleuropneumonia (CBPP) is a contagious infection of cattle caused by a mycoplasma, M. mycoides subsp. mycoides SC (MmmSC). It induces lesions of pleuropneumonia in acute cases and the formation of pulmonary "sequestra" in chronic cases. The disease is prevalent mostly in Africa, where it is responsible for high losses, but it has also been sporadically present in Southern Europe until 1999. Vaccination is now prohibited in most countries except in Africa. An empirical "inoculation" procedure was developed as early as 1852 in Europe but it may have been used even earlier in Africa. The inoculation of pleural fluid was performed at the tip of the tail in Europe and on the bridge of the nose in Africa. It conferred good protection but induced a high number of fatal cases. Various inactivated preparations have been tested in the past with inconclusive results leading sometime to some protection and some other time to a sensitisation of the immunised animals. Such preparations have never been used in the field. Attenuated MmmSC strains have been developed in the 1950s and used extensively in the field both in Africa and Australia. The best known vaccine strains are KH3J, T1/44 and T1sr. Vaccination campaigns have succeeded in reducing considerably the CBPP prevalence in these two continents but eradication was achieved in Australia only by switching to strict measures of animal movement control and a stamping-out policy. The search for new CBPP vaccines has become a major issue for African countries that are facing an increase in outbreaks. The rationale for this search is based on a better understanding of the mycoplasma virulence mechanisms that could lead to a targeted attenuation of MmmSC strains. It is also based on a better understanding of the bovine immune response that may be driven to a pathogenic inflammatory response or conversely to a better balanced response leading to protection.
牛传染性胸膜肺炎(CBPP)是由丝状支原体丝状亚种(MmmSC)引起的牛传染性感染病。急性病例会引发胸膜肺炎病变,慢性病例会形成肺部“隔离区”。该病主要在非洲流行,造成了巨大损失,但直到1999年,它也曾在南欧零星出现。除非洲外,目前大多数国家已禁止接种疫苗。早在1852年欧洲就研发出了一种经验性的“接种”方法,甚至在非洲可能更早便已使用。在欧洲,接种胸膜液是在牛尾尖进行,在非洲则是在鼻梁处。这种方法能提供良好的保护,但会导致大量死亡病例。过去曾对各种灭活制剂进行过测试,结果不一,有时能提供一定保护,有时却会使免疫动物致敏。此类制剂从未在实际中使用过。20世纪50年代研发出了减毒的MmmSC菌株,并在非洲和澳大利亚广泛应用于实际。最著名的疫苗菌株是KH3J、T1/44和T1sr。疫苗接种运动成功大幅降低了这两个大陆的CBPP流行率,但澳大利亚仅通过转向严格的动物移动控制措施和扑杀政策才实现了根除。对于面临疫情增加的非洲国家而言,寻找新的CBPP疫苗已成为一个重大问题。进行这一探索的依据是,更好地了解支原体毒力机制,这可能会导致对MmmSC菌株进行有针对性的减毒。同时也是基于对牛免疫反应的更好理解,这种免疫反应可能会引发致病性炎症反应,或者相反,引发更平衡的反应从而实现保护。