evidence: Vinita Dubey, associate medical officer of health at Toronto Public Health, told AFP that if worn correctly, a cloth mask is unlikely to reduce oxygen enough that the wearer would pass out and that "prolonged use of a face mask, including the N95, has not been shown to cause carbon dioxide toxicity in healthy people". [...] AFP also took aim at a viral video in which a woman claimed that mask-wearing hurts the immune system and does not protect from COVID-19. [...] As to whether masks hurt the immune system, Sheeley Payne, of the University of Texas, told AFP, "there is no evidence that masks or gloves reduce the normal microbiota or predispose people to opportunistic infections".