Use of serological analysis methods and interpretation of results

An ideal method of analysis should identify all the infected subjects, i.e., no false negatives, while at the same reportingonly infected subjects, i.e., no false positives. The frequency of such false results will determine the validity of thetest, the reliability of the positive and negative results obtained, and the sampling plan. Although laboratory analysis, and especially serology, represents advances in current veterinary practice, it should be used with care. The number of analyses carried out is often crucial to the relevance and useful interpretation of the results. Proving that a herd or an animal is infected is fairly easy and unequivocal, but proving it is not infected is much more difficult.