: How accurate are dogs to detect whether a human has COVID-19? I read on https://www.businessinsider.com/sniffer-dogs-answer-to-the-covid-19-testing-crisis-mirror-2020-4: Medical detection dogs able to sniff 750 people an

The 2020 study {1} found that dogs can detect COVID-19 with a sensitivity of 82.63% and a specificity of 96.35%:

The dogs were able to discriminate between samples of infected (positive) and non-infected (negative) individuals with average diagnostic sensitivity of 82.63% (95% confidence interval [CI]: 82.02–83.24%) and specificity of 96.35% (95% CI: 96.31–96.39%). During the presentation of 1012 randomised samples, the dogs achieved an overall average detection rate of 94% (±3.4%) with 157 correct indications of positive, 792 correct rejections of negative, 33 incorrect indications of negative or incorrect rejections of 30 positive sample presentations.

Sample size: 8 dogs, 1012 samples. Note that, as expected, there is variability between dogs in terms of sensitivity and specificity, as shown in Table 2.
YouTube video from the authors:

Reddit thread commenting on that study and its caveats: redd.it/hz3d9m (mirror).

References:

{1} Jendrny, Paula, Claudia Schulz, Friederike Twele, Sebastian Meller, Maren von Köckritz-Blickwede, Albertus Dominicus Marcellinus Erasmus Osterhaus, Janek Ebbers et al. "Scent dog identification of samples from COVID-19 patients–a pilot study." BMC Infectious Diseases 20, no. 1 (2020): 1-7. doi.org/10.1186/s12879-020-05281-3

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