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Bill Gates says he had to tell Trump HIV and HPV are different. Twice

Gates was speaking to a crowd about his first two meetings with the US president, neither of which seemed to go too well.

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Bill Gates has previously said President Donald Trump tried to hire him as the White House science adviser. A new clip of Gates talking about his first two meetings with Trump, obtained by MSNBC, may show why the tech innovator turned down the role.

Among other anecdotes, Gates is seen telling an audience about how, in both of his meetings with Trump, the president asked if there's a difference between HIV and HPV. The crowd was of Bill & Melinda Gates Foundation employees, according to MSNBC. 

"He wanted to know if there was a difference between HPV and HIV," Gates is seen saying, "so I was able to explain that those are rarely confused with each other."   

HIV, or human immunodeficiency virus, causes AIDS, while HPV is an infection that can cause cervical cancer. The Bill & Melinda Gates Foundation has donated huge amounts of money to HIV treatment and prevention, including $100 million in 2002 and $140 million in 2016.  

Gates' first meeting with Trump was in 2016, with the second in March 2017. The topic of vaccines was also brought up in both. 

"In both of those two meetings, he asked me if vaccines weren't a bad thing, because he was considering a commission to look into ill effects of vaccines," Gates said. "I said, no, that's a dead end, that would be a bad thing, don't do that."

In Gates' most recent meeting with Trump, which happened two months ago in March, Trump offered the Microsoft founder the position of White House science adviser, Gates told STAT News in an interview. 

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"That's not a good use of my time," Gates responded to the president, as relayed to STAT. He noted that he's not sure if Trump actually was serious about the job offer.

"I didn't put him to the test, whether that was a serious thing or not," Gates said. "He probably himself didn't know if he was serious. It was a friendly thing. He was being friendly."