ABSTRACT
Background The main strategy to contain the current SARS-CoV-2 pandemic remains to implement a comprehensive testing, tracing and quarantining strategy until vaccination of the population is adequate.
Methods Ten dogs were trained to detect SARS-CoV-2 infections in beta-propiolactone inactivated saliva samples. The subsequent cognitive transfer performance for the recognition of non-inactivated samples were tested on saliva, urine, and sweat in a randomised, double-blind controlled study.
Results Dogs were tested on a total of 5242 randomised sample presentations. Dogs detected non-inactivated saliva samples with a diagnostic sensitivity of 84% and specificity of 95%. In a subsequent experiment to compare the scent recognition between the three non-inactivated body fluids, diagnostic sensitivity and specificity were 95% and 98% for urine, 91% and 94% for sweat, 82%, and 96% for saliva respectively.
Conclusions The scent cognitive transfer performance between inactivated and non-inactivated samples as well as between different sample materials indicates that global, specific SARS-CoV-2-associated volatile compounds are released across different body secretions, independently from the patient’s symptoms.
Funding The project was funded as a special research project of the German Armed Forces. The funding source DZIF-Fasttrack 1.921 provided us with means for biosampling.
Competing Interest Statement
The authors have declared no competing interest.
List of abbreviations
- RT-PCR
- reverse transcription polymerase chain reaction test
- VOCs
- volatile organic compounds
- DDTS
- Dog Detection Training System
- BPL
- beta-propiolactone
- TP
- true positive
- FP
- false positive
- TN
- true negative
- FN
- false negative
- CI
- confidence interval
- TADD
- Training Aid Delivery Device
