Bill Gates, the billionaire businessman and founder of Microsoft, mocked President Donald Trump at a talk before his foundation, claiming the president repeatedly asked him the difference between HIV and HPV and made his wife uncomfortable.

In video obtained by Chris Hayes and aired on his MSNBC show All In, Gates dishes on several meetings he had with Trump, a fellow billionaire businessman, at Trump Tower and The White House.

Speaking before Gates Foundation staff, he revealed that the president (who once said evading sexually transmitted diseases in the 1990s was his own personal Vietnam) didn’t know the difference between HIV, the virus that can lead to AIDS, and HPV, an infection that can cause genital warts and cancer.

“Both times he wanted to know if there was a difference between HIV and HPV,” Gates said, as the crowd of his staffers burst out laughing. “So I was able to explain that those are rarely confused with each other.”

Trump has often expressed his belief in the conspiracy theory that vaccines cause autism, and Gates said that the president invited him to the White House in March, 2017 to discuss forming a commission to address the supposed link.

“In both of those two meetings, he asked me if vaccines weren’t a bad thing,” Gates said, adding he advised him dump the idea and embrace science and innovation.

Gates said The philanthropist explained that he never met Trump until he was elected, and that there was one moment during the election when they were in the same place and Gates “avoided him.”

Gates continued that Trump knew his daughter Jennifer Gates, and when Bill eventually met with the newly elected president in December, 2016, Trump spoke to Jen and “was being super nice.”

“So when I first talked to him, it was actually kind of scary how much he knew about my daughter’s appearance,” Gates said. “Melinda didn’t like that too much.”

“And then like 20 minutes later he flew in in a helicopter to the same place,” Gates said of the encounter. “So clearly he had been driven away, and he wanted to make a grand entrance in a helicopter.”

The philanthropist also recounted an anecdote from the first time he met Trump, and the president referred to himself in the third person.

“His first sentence kind of threw me off, [Trump] said: ‘Trump hears that you don’t like what Trump’s doing.’ And I thought, ‘Wow… But you’re Trump?’ So I didn’t know if the third-party form was what was expected. ‘Gates says, Gates knows that you’re not doing things right,'” he joked.

Watch above, via MSNBC.

[image via screengrab]

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