I looked it up and it isn't. Hard to kill a virus that has never been isolated and cultured. A group of investigators sent Freedom of Information requests to the CDC and about 200 other health agencies and laboratories around the world asking for evidence that a virus had been isolated. All returned answers stating that they had no cultures or other documentary evidence of Covid-19. There are lots of interesting questions concerning the science of virology and worth investigating. I had always accepted what I was taught about viruses in medical school fifty years ago and only started looking it to it in any depth during the Covid period and what I have learned has changed my outlook considerably.