Taylor-Robinson D
Dev Biol Stand. 1975;28:86-100.
In contrast to the uncertain role of mycoplasmas in genital disease, there is no doubt that they produce respiratory disease. The first mycoplasma isolated, M. mycoidesis is the aetiological agent of bovine pleuropneumonia, a disease now confined to parts of Africa and Australia. M. capri causes a similar disease in goats which is geographically more widespread. Enzootic pneumonia of pigs, seen in various parts of the world, is due primarily to M. suipneumoniae. Although some strains of M. hyorhinis also seem capable of causing disease. Not all strains of a mycoplasma species are equally pathogenic; only some strains of M. pulmonis produce severe respiratory disease in mice and rats. Further, concomitant infection with other agents may result in more severe disease; this is particularly seen in M. gallisepticum infections of poultry. Of those mycoplasmas which infect man, only M. pneumoniae is known to cause respiratory disease, mainly involving the younger age groups. Mycoplasmas spread by close contact so that disease is seen in family groups or where there is crowding or herding. Factors in resistance to respiratory disease caused by mycoplasmas have been poorly understood but the importance of local immunity is becoming more clear.
与支原体在生殖器疾病中作用不确定形成对比的是，它们会引发呼吸道疾病这一点毫无疑问。最早分离出的支原体，丝状支原体是牛传染性胸膜肺炎的病原体，这种疾病目前局限于非洲和澳大利亚的部分地区。山羊支原体在山羊中引发类似疾病，在地理分布上更为广泛。世界各地都可见到的猪地方流行性肺炎，主要是由猪肺炎支原体引起的。尽管一些猪鼻支原体菌株似乎也有致病能力。并非支原体物种的所有菌株都具有同等致病性；只有部分肺炎支原体菌株会在小鼠和大鼠中引发严重的呼吸道疾病。此外，与其他病原体的合并感染可能导致更严重的疾病；这在鸡败血支原体感染家禽时尤为明显。在感染人类的支原体中，已知只有肺炎支原体会引发呼吸道疾病，主要累及较年轻人群。支原体通过密切接触传播，因此在家庭群体或人员拥挤、饲养密集的地方会出现疾病。人们对抵抗支原体引起的呼吸道疾病的因素了解甚少，但局部免疫的重要性正变得越来越清晰。
