WHO: Vaccine Market Report Highlights Inequitable Global Distribution

Infections at Mass Events Dogs trained to detect SARS-CoV-2 infection by smell correctly identified individuals with active infections at concerts with a specificity of nearly 100% and a sensitivity of 82%, researchers reported in BMJ Global Health. The results suggest that dogs may provide a fast and reliable screening option for public events at which mass screening is required. Eight trained dogs of various breeds were presented with sweat samples from 2802 concertgoers at 4 events in Germany organized for the study. Each person underwent SARS-CoV-2 antigen and polymerase chain reaction (PCR) testing at the concert, but the investigators, dog handlers, and dogs did not know the results. Most of the human participants were vaccinated against COVID-19 but this did not affect the dogs’ ability to detect active infections. Sweat samples collected previously from 38 patients with SARS-CoV-2 infections were randomly introduced into the test lineup, raising the total sample prevalence to 1.34% from a background rate of 0.2%. A positive finding was confirmed by a second dog sniffing the same sample. It took about 1 to 2 seconds for the dogs to smell each sample. The dogs turned up only 2 false-positive results and 1 false-negative result. Positive identification of SARS-CoV-2 infection by 2 dogs was confirmed for another patient by a PCR test 2 days later, suggesting that dogs may be able to detect an infection before virus shedding, the authors wrote. Overall, the canine test had a positive predictive value of 70% and a negative predictive value of 99.7% assuming a prevalence rate of 0.2%. Previous studies found that dogs can identify SARS-CoV-2 infections with high diagnostic accuracy, but the new research demonstrated it under real-world mass screening conditions, the authors wrote. Medical scent-detection dogs provide an additional opportunity to control the ongoing COVID-19 pandemic and possibly future pandemics, especially in areas or countries with limited test infrastructure or financial means, they concluded.