Strange devices have been cropping up on the lapels of political figures around the world. Sometimes known as Air Doctor and sometimes as Virus Shut Out, they look like normal ID badges. But according to their manufacturers, they use chemicals to wipe out airborne pathogens and protect wearers from disease. 

The cards have been sported as talismans against Covid-19 by a number of prominent people including Vladimir Putin’s spokesman Dmitry Peskov – until he was hospitalized with the coronavirus last week. Bolivia’s interim president Jeanine Áñez was recently spotted with one hanging around her neck. Lebanese political leaders Gebran Bassil and Nabih Berri have also been seen wearing the badges. 

One such device — the Air Doctor — sells for $20.95. It releases small amounts of chlorine dioxide, which its makers say can kill airborne pathogens, including the coronavirus. However, there is so far only anecdotal evidence that Covid-19 can spread in this way. 

Air Doctor’s representatives maintain that the device does not protect the wearer against person-to-person transmission, which, according to the U.S. Center for Disease Control and the World Health Organization, is the main way the virus is contracted.