"Real" tests are also subject to false positives and false negatives. What you are suggesting is to ignore the possibility that dog sniffing may result in fals

"Real" tests are also subject to false positives and false negatives. What you are suggesting is to ignore the possibility that dog sniffing may result in false negatives, and administer a "real" test to anyone who's identified by a dog to be positive. Keep in mind that under reasonable assumptions, half of those people are false positives. A portion of them will falsely test positive again. However, some of the true dog test positives (anywhere between 2% - 25% of them) will falsely test negative. Therefore, this strategy will result in more infected people not being quarantined.