“I have blogged previously about the dangerous and deadly effects of science denialism, from the innocent babies unnecessarily exposed to deadly diseases by other kids whose parents are anti-vaxxers, to the frequent examples of how acceptance of evolution helps us stop diseases and pests (and in the case of Baby Fae, rejection of evolution was fatal), to the long-term effects of climate denial to the future of the planet we all depend upon. But one of the strangest forms of denialism is the weird coalition of people who refuse to accept the medical fact that the HIV virus causes AIDS. What the heck? Didn’t we resolve this issue in the 1980s when the AIDS condition first became epidemic and the HIV virus was discovered and linked to AIDS? Yes, we did—but for people who want to deny scientific reality, it doesn’t matter how many studies have been done, or how strong the scientific consensus is. There are a significant number of people out there (especially among countries and communities with high rates of AIDS infections) that refuse to accept medical reality. I described all of these at greater length in my new book Reality Check: How Science Deniers Threaten our Future.”