The claim that masks do not protect people from viruses is indeed false. The user who commented this on Bluesky does not appear to have any medical expertise, and their rejection of the CDC's information is unfounded. According to the CDC, masks can reduce the spread of viruses when worn by infected individuals and can also protect wearers from inhaling germs. The CDC is a trusted source, and its guidance is supported by other reputable organizations like the Mayo Clinic and CBS. While it's true that one reason doctors wear masks is to protect against blood and bodily fluid splashes during surgery. this does not negate the effectiveness of masks in preventing viral transmission. The type of mask and the specific virus are important factors in determining the level of protection. For example, N95 respirators offer more protection than standard face masks. Overall, the claim that masks have "zero efficiency against viruses" is misleading and false. Masks, especially high-quality ones like N95 respirators, are effective in reducing the transmission of viruses.