Smith T H, Fox L K, Middleton J R
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman 99164-6610, USA.
J Am Vet Med Assoc. 1998 Feb 15;212(4):553-6.
The Washington State University dairy experienced an outbreak of intramammary infections (IMI) caused by Staphylococcus aureus during autumn 1993 through summer 1995. The outbreak was believed to be a result of transmission of 1 strain of S aureus in a herd that historically had excellent control of contagious mastitis. Control practices included strict hygiene at time of milking and preferential culling of cows infected with S aureus. Mastitis caused by Streptococcus agalactiae was not found in this herd. Despite excellent control practices, the strain of S aureus caused a new infection rate of approximately 3% of the herd per month. Moreover, a second strain of S aureus, isolated from a cow with mastitis, was introduced into the herd experimentally, and it failed to transmit disease. The outbreak of S aureus mastitis in this herd was eventually controlled by maintaining a program of strict milking time hygiene, by intensifying the program of preferentially culling infected cows, and by segregating cows with S aureus IMI in a separate pen and milking these infected cows last.
1993年秋季至1995年夏季期间，华盛顿州立大学奶牛场爆发了由金黄色葡萄球菌引起的乳房内感染（IMI）。此次疫情被认为是由1株金黄色葡萄球菌在一个历史上对传染性乳腺炎控制良好的牛群中传播所致。控制措施包括挤奶时严格的卫生条件以及优先淘汰感染金黄色葡萄球菌的奶牛。该牛群未发现无乳链球菌引起的乳腺炎。尽管采取了出色的控制措施，但金黄色葡萄球菌菌株每月仍导致该牛群约3%的新感染率。此外，从一头患乳腺炎的奶牛身上分离出的第二株金黄色葡萄球菌被实验性引入该牛群，但未能传播疾病。通过维持严格的挤奶时间卫生计划、加强优先淘汰感染奶牛的计划以及将患有金黄色葡萄球菌IMI的奶牛隔离在单独的围栏中并最后挤这些感染奶牛的奶，该牛群的金黄色葡萄球菌乳腺炎疫情最终得到了控制。
