Relevant research data disclosed in Germany shows that in the formal random test, the sensitivity of the detection dog to the COVID-19 detection is 83%, and the specificity is 96%. The sensitivity is 83%, which means that out of 100 positive samples, the test dog can correctly find 83; the specificity is 96%, which means that out of 100 negative samples, the test dog can correctly determine 96.
Question: The virus has no smell, how can dogs smell it?
After the human body is infected with the virus, the body's normal metabolism will be affected, and some special volatile metabolites will be released. Detection dogs are not able to smell the COVID-19, but can smell these volatile substances.
Challenges and limitations: Should testing dogs really be on duty?
- The detection dog can detect a small number of samples, but it does not guarantee that it can be competent to detect a large number of samples. Assuming that the UAE airport where the detection dog is on duty has 200,000 passenger traffic per day, according to the news, it takes 1 minute for the detection dog to identify a sample. That day, it works 8 hours and can only process 480 samples. To deal with 200,000 passengers, more than 400 detection dogs are needed.
- In the course of the experiment, because there are always positive samples of the COVID-19, and the researchers can give them rewards in a short period of time after the test dogs have made the correct judgment, so they can be actively strengthened. In real-world applications, testing dogs may need to find a positive sample among thousands of negative samples. In the absence of rewards, this may be a very boring task for them. More importantly, in the real world, even if the test dog makes the correct choice, the tester cannot confirm whether their choice is correct (because the samples found by the test dog must be confirmed by RT-PCR and other tests). This kind of delay will result in the detection dogs being unable to be rewarded in time after making the right choice, thereby "damaging" their enthusiasm.
- The risk of detecting the virus in dogs may not be high, but it is always present. Moreover, the heavy workload does not guarantee that the dog's condition remains the same. It is better to rely on scientific and technological means to be reliable. Detection of dogs can only be said as an attempt and supplement.