Oxygen shortage in India sparks hunt for $1,000 concentrators File photo of oxygen concentrators recieved in India - PTI× After a new coronavirus variant unleashed a brutal wave of infections, demand has shot up for the device Raphael Koch, a retailer of medical devices in the small Swiss town of Wil, has been busy for the past two weeks fielding a flurry of phone calls. Most are from Indians or India-based companies looking for oxygen concentrators, with some even wanting as many as 500 at once. But Koch’s Oxymed store barely has any stock left of the little known machines that separate the critical gas from air and assist patients with low blood-oxygen levels. And he isn’t expecting fresh supplies from manufacturers at least until mid-June.