Warning: Hand sanitizers will not make you invincible. They don’t, for example, protect against germs like MRSA, as the FDA pointed out yesterday in a consumer update. Nor do they kill E. coli, salmonella, or the H1N1 virus. It’s not just consumers who don’t get this: The FDA yesterday fired off a round of warning letters to firms that falsely say their sanitizers fight MRSA, the Washington Post notes. In general, the CDC says, soap and water are preferable to sanitizers. (More hand sanitizer stories.)