Jobert J L, Savoye C, Cariolet R, Kobisch M, Madec F
Agence Française de Sécurité Sanitaire des Aliments, Zoopôle, Ploufragan, France.
Can J Vet Res. 2000 Jan;64(1):21-6.
In order to demonstrate the possible role of aerosol in the transmission of Actinobacillus pleuropneumoniae, an experiment including 18 specific pathogen-free (SPF), 10-week-old piglets, randomly distributed into 2 adjacent units, was carried out. In these facilities, air was forced through absolute filters to prevent any contact with infectious agents. During the first 6 d post inoculation, the 2 units were connected by a rectangular opening and the air circulation was forced by the ventilation system from unit A (inoculated pigs) to unit B (non-inoculated pigs). The A. pleuropneumoniae strain (biovar 1 serovar 9) was isolated in France from an outbreak of porcine pleuropneumonia. Two different infecting doses, 10(7) cfu/animal and 10(8) cfu/animal, were inoculated by intranasal route in 6 pigs of unit A. The infection spread quickly from the inoculated pigs to the non-inoculated pigs. Clinical signs were acute during the 4 d post inoculation: hyperthermia, respiratory distress and, sometimes, death (6 pigs of the unit A and 2 pigs of the unit B). All pigs seroconverted against A. pleuropneumoniae serovar 9 within 2 weeks. Lung lesions were severe: fibrinous pleurisy and lung hemorrhages in the acute stage, pleural adherences and focal pulmonary necrosis in the chronic stage. Actinobacillus pleuropneumoniae was isolated from the tonsils and/or lungs in 16 animals. It could be also isolated from the air of the experimental unit. This study showed that A. pleuropneumoniae was readily transmitted through aerosol over a distance of at least 2.5 m.
为了证明气溶胶在胸膜肺炎放线杆菌传播中可能发挥的作用，进行了一项实验，该实验包括18头10周龄的无特定病原体（SPF）仔猪，随机分布在相邻的两个单元中。在这些设施中，空气通过绝对过滤器强制流通，以防止与传染源接触。在接种后的前6天，两个单元通过一个矩形开口相连，通风系统迫使空气从单元A（接种猪）流向单元B（未接种猪）。胸膜肺炎放线杆菌菌株（生物变种1血清型9）是在法国从一次猪胸膜肺炎疫情中分离出来的。通过鼻腔途径给单元A的6头猪接种了两种不同的感染剂量，即每头动物10⁷cfu和10⁸cfu。感染迅速从接种猪传播到未接种猪。接种后4天内临床症状急性发作：体温过高、呼吸窘迫，有时还会死亡（单元A的6头猪和单元B的2头猪）。所有猪在2周内均针对胸膜肺炎放线杆菌血清型9发生血清转化。肺部病变严重：急性期为纤维素性胸膜炎和肺出血，慢性期为胸膜粘连和局灶性肺坏死。从16只动物的扁桃体和/或肺中分离出了胸膜肺炎放线杆菌。在实验单元的空气中也能分离到该菌。这项研究表明，胸膜肺炎放线杆菌很容易通过气溶胶在至少2.5米的距离内传播。
