https://www.stltoday.com/news/national/not-real-news-misinformation-that-s-spreading-like-a-virus/article_2dbd16f9-f22d-5b4d-b11a-1831eac51bf4.html
CLAIM: There is a simple self-check that can be done every morning to see if you have the coronavirus. Take a deep breath and hold it for more than 10 seconds. If you complete it successfully without discomfort, stuffiness or tightness it proves there is no fibrosis in the lungs, basically indicating no infection.
THE FACTS: Medical experts say that the test would not provide a clear indication of whether someone has the virus. The claim, which has three parts, first says that if a coronavirus patient goes to the hospital too late their lungs will experience 50 percent fibrosis, scarring of the lungs that restricts breathing. It then suggests the 10 second breathing test, finally stating that drinking water every 15 minutes will kill the virus. Social media users have falsely attributed the claims to Japanese doctors, Taiwanese experts and Stanford University. Lisa Kim, Stanford Health Care and school of medicine spokeswoman, said in an email that the widely distributed breathing test claim did not come from Stanford University. Despite medical experts and even the World Health Organization debunking these claims, people continue to share them on and off social media. Dr. Robert Legare Atmar, an infectious disease specialist at Baylor College of Medicine, told The Associated Press that there is no clear evidence that coronavirus causes 50 percent pulmonary fibrosis. Experts also said that the 10 second test being shared online would not be a reliable way to determine whether someone has the virus. “This approach may be helpful in identifying persons with more serious lung disease,” Atmar said. "But it will not identify persons who are infected and have mild to no symptoms.” There are many things beyond coronavirus that could lead to restricted breathing, including asthma, anxiety or heart disease, said Dr. Gregory Poland, head of vaccine research at Mayo Clinic in Rochester, Minnesota. Also, while staying hydrated by drinking water is important for overall health, it does not prevent coronavirus, according to the WHO.