Word Count: 405 Two dogs could accurately scan 300 plane passengers in about half an hour as part of a rapid screening strategy, scientists from the London School of Hygiene and Tropical Medicine said in research published Monday. Then only the people selected by the dogs would need to undergo a PCR test. There’s growing evidence that dogs can identify Covid patients in much the same way they sniff out bombs, drugs or other diseases. Pathogens produce unique volatile organic compounds released by ailing cells. These signature smells could be used to fight outbreaks earlier on in the future, the researchers wrote, arguing the approach is fast, cheap and non-invasive.