Use Of Canine Olfactory Detection For COVID-19 Testing Study On U.A.E. Trained Detection Dog Sensitivity

Abstract

This study aimed to evaluate the sensitivity of 21 dogs belonging to different United Arab Emirates (UAE) Ministry of Interior (MOI), trained for COVID-19 olfactory detection.The study involved 17 explosives detection dogs, two cadaver detection dogs and two dogs with no previous detection training. Training lasted two weeks before starting the validation protocol. Sequential five and seven-cone line-ups were used with axillary sweat samples from symptomatic COVID-19 individuals (SARS-CoV-2 PCR positive) and from asymptomatic COVID-19 negative individuals (SARS-CoV-2 PCR negative). A total of 1368 trials were performed during validation, including 151 positive and 110 negative samples. Each line-up had one positive sample and at least one negative sample. The dog had to mark the positive sample, randomly positioned behind one of the cones. The dog, handler and data recorder were blinded to the positive sample location.The calculated overall sensitivities were between 71% and 79% for three dogs, between83% and 87% for three other dogs, and equal to or higher than 90% for the remaining 15 dogs (more than two thirds of the 21 dogs).After calculating the overall sensitivity for each dog using all line-ups, “matched” sensitivities were calculated only including line-ups containing COVID-19 positive and negative samples strictly comparable on confounding factors such as diabetes, anosmia, asthma, fever, body pain, diarrhoea, sex, hospital, method of sweat collection and sampling duration. Most of the time, the sensitivities increased after matching.Pandemic conditions in the U.A.E., associated with the desire to use dogs as an efficient mass-pretesting tool has already led to the operational deployment of the study dogs.Future studies will focus on comparatives fields-test results including the impact of the main COVID-19 comorbidities and other respiratory tract infections.

Sars-Cov-2 Virus Infected Patient Identification Through Canine Olfactive Detection on Axillary Sweat Samples

“…Specificity results ranged from 78% to 92%, 6 dogs being above 85% and 4 being above 90%. These numbers appear to be consistent with the ones obtained by Jendrny [4], Eskandari [6], Bjorkman [76], Sarkis [77] and Grandjean [78], who also worked on sweat samples. When using urine samples and then saliva samples, deactivated by detergent, Essler [7] obtained more mixed results, whereas Vesga [5], working on respiratory secretions and saliva, showed sensitivities from 6 dogs ranging between 90% and 98%, and specificities higher than 99%.…”

Canine olfactory detection and its relevance to medical detection

“…The use of biomedical detection dogs for various infectious and non-infectious diseases like Helicobacter pylori [7], different cancer types [8][9][10][11][12][13][14][15][16][17], hypoglycaemia in diabetes mellitus patients [18][19][20], epileptic seizures [21], bacteriuria [22], bovine virus diarrhoea [23], COVID-19 [24][25][26][27][28][29][30][31][32][33], Malaria [34] and Clostridium difficile-infections [35] is still in its infancy (Table 1). Most of these studies indicate a disease-specific body odour or a specific volatile organic compound (VOC)-pattern associated with metabolic changes secondary to an infection [36].…”

“…The aim of this study was to evaluate the dog method as a "point-of-care" diagnostic tool [35]. Lastly, it was also possible to train dogs to detect viral infections with bovine viruses [23] or with the coronavirus SARS-CoV-2 in various body fluids [6,[24][25][26][27][28][29][30][31][32][33] with high rates of diagnostic accuracy. Realtime methods for the identification of viral infections are often limited or not existing, especially for resource-limited environments.…”

“…Recently, there is a rapid, growing body of evidence for detection dogs being used for identifying SARS-CoV-2 infected individuals [24][25][26][27][28][29][30][31][32][33]. In the SARS-CoV-2 detection dog studies, different sample material, study designs and dog breeds were used in different countries.…”

“…Some researchers used distractors (samples from individuals suffering from other respiratory diseases than COVID-19) in the training and testing phases, which were slightly different from the target scent to better represent conditions in the field where other respiratory diseases different from COVID-19 will be to be also presented. A wide variety of human body fluids (saliva, tracheobronchial secretions, urine, sweat) as well as nasopharyngeal swabs, breath samples and masks or clothing were used as sample materials for presentation to dogs during training and testing [24][25][26][27][28][29][30][31][32][33]. Interestingly, dogs trained with saliva samples were also able to detect samples of infected individuals in sweat and urine without further training which is indicative for a successful generalisation process [25].…”