Sutmoller P, McVicar J W
Infect Immun. 1972 Nov;6(5):718-22. doi: 10.1128/iai.6.5.718-722.1972.
After infection of the upper respiratory tract with foot-and-mouth disease (FMD) virus in immunized cattle, a drop in specific serum-neutralizing antibody activity was observed. Vaccinated cattle with high preexposure serum antibody titers had a precipitous drop for the first 4 days after virus exposure, followed by a rise in titer. This drop was also seen in passively immunized cattle with high preexposure titers; however, their antibody titers decreased for 5 to 7 days after exposure to virus. Some vaccinated and passively immunized cattle with low preexposure antibody titers showed fluctuations in their titers shortly after exposure. These data suggest that the course of infection with FMD virus in immunized cattle depends on the rapidity of new antibody formation as well as on the level of neutralizing antibody titer at the time of exposure.
在免疫牛的上呼吸道感染口蹄疫（FMD）病毒后，观察到特异性血清中和抗体活性下降。暴露前血清抗体滴度高的接种牛在病毒暴露后的前4天抗体滴度急剧下降，随后滴度上升。这种下降在暴露前滴度高的被动免疫牛中也可见；然而，它们的抗体滴度在接触病毒后5至7天下降。一些暴露前抗体滴度低的接种和被动免疫牛在暴露后不久其滴度出现波动。这些数据表明，免疫牛感染FMD病毒的过程取决于新抗体形成的速度以及暴露时中和抗体滴度的水平。
