EVALUATION OF CANINE DETECTION OF COVID-19 INFECTED INDIVIDUALS UNDER
CONTROLLED SETTINGS
Abstract
RT-PCR is currently the standard diagnostic method to detect symptomatic
and asymptomatic individuals infected with SARS-CoV-2. However, RT-PCR
results are not immediate and may falsely be negative before an infected
individual sheds viral particle in the upper airway where swabs are
collected. Infected individuals emit volatile organic compounds (VOCs)
in their breath and sweat that are detectable by trained dogs. Here we
evaluate the diagnostic accuracy of dog detection against SARS-CoV-2
infection. Fifteen dogs previously trained at two centres in Australia
were presented to axillary sweat specimens collected from known
SARS-CoV-2 human cases and non-cases. The true infection status of the
cases and non-cases were confirmed based on RT-PCR results as well as
clinical presentation. Across dogs, the overall diagnostic sensitivity
(DSe) was 95.6% (95%CI: 93.6%-97.6%) and diagnostic specificity
(DSp) was 98.1% (95%CI: 96.3%-100.0%). The DSp decreased
significantly with non-case specimens sourced from UAE ( P-value
< 0.001). The location of evaluation did not impact the
detection performances. The accuracy of detection varied across dogs and
experienced dogs revealed a marginally better DSp ( P-value =
0.003). The potential and limitations of this alternative detection tool
are discussed.