Scientists in the Netherlands have trained bees to identify COVID-19 through their sense of smell. The research was conducted on more than 150 bees in Wageningen University's bio-veterinary research laboratory.
The scientists had trained the bees by giving them a treat which consists of a sugar-water solution every time they were exposed to the scent of a mink infected with COVID-19. Each time the bees were exposed to a non-infected sample, they wouldn't get a reward. This is through a process known as Pavlovian conditioning.
Eventually, the bees could identify an infected sample within a few seconds - and would then stick out their tongues like clockwork to collect the sugar water.
Researchers have also trained dogs to detect covid from human saliva or sweat with fairly high levels of accuracy. A study at German found that dogs could identify positive COVID-19 samples 94% of the time.
That's because metabolic changes from the coronavirus make an infected person's body fluids smell slightly different than those of a non-infected person. But researchers still aren't sure whether animals are the best bet for snuffling out COVID-19 cases outside the lab.
It is not sure if they can replace a PCR test, but they could be very promising. Certain animals could be useful for identifying COVID-19 in places or countries in which high-tech laboratory equipment is scarce or inaccessible.
Wageningen scientists are also working on a prototype of a machine that could automatically train multiple bees at once, and then uses their skills to test for coronavirus aerosols (tiny virus-laden particles) in the surrounding environment.