Diagnostic accuracy of non-invasive detection of SARS-CoV-2 infection by canine olfaction
This article has been Reviewed by the following groups
Listed in
- Evaluated articles (ScreenIT)
Abstract
Throughout the COVID-19 pandemic, testing individuals remains a key action. One approach to rapid testing is to consider the olfactory capacities of trained detection dogs.
Methods
Prospective cohort study in two community COVID-19 screening centers. Two nasopharyngeal swabs (NPS), one saliva and one sweat samples were simultaneously collected. The dog handlers (and the dogs…) were blinded with regards to the Covid status. The diagnostic accuracy of non-invasive detection of SARS-CoV-2 infection by canine olfaction was assessed as compared to nasopharyngeal RT-PCR as the reference standard, saliva RT-PCR and nasopharyngeal antigen testing.
Results
335 ambulatory adults (143 symptomatic and 192 asymptomatic) were included. Overall, 109/335 participants tested positive on nasopharyngeal RT-PCR either in symptomatic (78/143) or in asymptomatic participants (31/192). The overall sensitivity of canine detection was 97% (95% CI, 92 to 99) and even reached 100% (95% CI, 89 to 100) in asymptomatic individuals compared to NPS RT-PCR. The specificity was 91% (95% CI, 72 to 91), reaching 94% (95% CI, 90 to 97) for asymptomatic individuals. The sensitivity of canine detection was higher than that of nasopharyngeal antigen testing (97% CI: 91 to 99 versus 84% CI: 74 to 90, p = 0.006), but the specificity was lower (90% CI: 84 to 95 versus 97% CI: 93 to 99, p = 0.016).
Conclusions
Non-invasive detection of SARS-CoV-2 infection by canine olfaction could be one alternative to NPS RT-PCR when it is necessary to obtain a result very quickly according to the same indications as antigenic tests in the context of mass screening.
Article activity feed
-
-
SciScore for 10.1101/2022.03.07.22271219: (What is this?)
Please note, not all rigor criteria are appropriate for all manuscripts.
Table 1: Rigor
Ethics IACUC: The protocol was approved for the dogs by the committee on the ethics of animal experiments of the Ecole Nationale Vétérinaire d’Alfort.
Consent: Informed consent was obtained from all subjects.Sex as a biological variable not detected. Randomization For samples that were processed by three or more dogs, only the results of two dogs were recorded at random. Blinding not detected. Power Analysis Statistical analysis: Sample size was calculated assuming that the sensitivity of the index tests was greater than or equal to 60%. Cell Line Authentication Contamination: Detection of other pathogens in saliva: The detection of other viruses (adenovirus, coronaviruses (229E, HKU1, NL63, and OC43), … SciScore for 10.1101/2022.03.07.22271219: (What is this?)
Please note, not all rigor criteria are appropriate for all manuscripts.
Table 1: Rigor
Ethics IACUC: The protocol was approved for the dogs by the committee on the ethics of animal experiments of the Ecole Nationale Vétérinaire d’Alfort.
Consent: Informed consent was obtained from all subjects.Sex as a biological variable not detected. Randomization For samples that were processed by three or more dogs, only the results of two dogs were recorded at random. Blinding not detected. Power Analysis Statistical analysis: Sample size was calculated assuming that the sensitivity of the index tests was greater than or equal to 60%. Cell Line Authentication Contamination: Detection of other pathogens in saliva: The detection of other viruses (adenovirus, coronaviruses (229E, HKU1, NL63, and OC43), human metapneumovirus A and B, influenza, influenza A H1, influenza A H3, influenza A H1N1/2009, influenza B, parainfluenza viruses (1, 2, 3, and 4), rhinovirus/enterovirus, respiratory syncytial virus A and B) and intracellular bacteria (Bordetella pertussis, Chlamydophila pneumoniae, and Mycoplasma pneumoniae) was performed in saliva samples with the multiplex test QIAstat-Dx® Respiratory SARS-CoV-2 Panel QIAStat (Qiagen, Courtaboeuf, France). Table 2: Resources
Software and Algorithms Sentences Resources The statistical analysis was performed using R software (http://cran.r-project.org/). http://cran.r-project.org/suggested: (CRAN, RRID:SCR_003005)Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).
Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:A limitation of non-invasive detection of SARS-CoV-2 infection by canine olfaction is the availability of trained dogs in this approach in light of the very significant needs if canine detection were to be considered as an alternative to antigenic tests. Another limitation is the need for certification of the dogs used for SARS-CoV-2 detection because of the risk of involving dogs whose diagnostic performance is inferior to those shown here. At the time of the study, there was no delta viriants detected, but there is no reason to believe that the results would have been different in the presence of the delta variants. To conclude, the results obtained in our prospective study involving 335 individuals who presented voluntarily in one of the APHP testing centers in Paris support the use of canine olfaction as an alternative to antigenic tests. Canine testing is non-invasive and provides immediate and reliable results. As for antigenic tests, positive results must be confirmed by RT-PCR, especially for variant screening. Further studies will be focused on direct sniffing by dogs to evaluate sniffer dogs for mass pre-test in airports, harbors, railways stations, cultural activities or sporting events. Axillary sweat testing could remain useful for small population testing or for mobile units acting on local clusters as an alternative to antigenic tests.
Results from TrialIdentifier: We found the following clinical trial numbers in your paper:
Identifier Status Title NCT04578509 Active, not recruiting Evaluation of a Screening Program for SARS-CoV-2 Infection i… Results from Barzooka: We did not find any issues relating to the usage of bar graphs.
Results from JetFighter: We did not find any issues relating to colormaps.
Results from rtransparent:- Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
- Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
- No protocol registration statement was detected.
Results from scite Reference Check: We found no unreliable references.
-
