SAN FRANCISCO (CBS SF) — Stanford Health Care’s Infectious Disease expert Dr. Anne Liu has been in the trenches, battling the COVID-19 pandemic since its earliest days. She’s seen patients die and has grown weary of celebrities like rapper Nicki Minaj spreading unsubstantiated rumors about the dangers of vaccinations.

Minaj made headlines last week when she noted in a tweet to her more than 22.6 million followers that the Met Gala required attendees to be vaccinated, and that she wouldn’t get the shot until “I feel I’ve done enough research.”

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She later issued a tweet sharing an unverified story about a cousin’s friend in Trinidad. Minaj asserted the unidentified individual “became impotent” and “his testicles became swollen” after receiving the shot.

“This is a tough topic,” Liu told CBSN Bay Area. “I have patients who have taken their time to get vaccinated and some of them eventually come around and some of them have died of COVID. When our unvaccinated patients died of COVID despite our best efforts to get them vaccinated, or to treat them even after they have gotten the infection, it’s really horrible.”

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“I blame the widespread lies and all the falsehoods and misinformation that people are fed. It’s very upsetting,” Liu added emotionally. “People who have huge audiences are on social media are casting doubts on topics that there is better information to be found on. The people we are seeing in the hospital with COVID are either unvaccinated or their immune systems are such that they cannot respond to the vaccine. And it is really devastating.”

When it comes to Minaj’s fertility claims, Lui said the science simply doesn’t support them.

“Up front, we have to say there are many causes of infertility and testicular swelling. The COVID vaccines are not on that list,” she said. “There is still a lot to be discovered whether the COVID infection can actually affect your fertility. The jury is out on that. But there is some data on COVID infection actually affecting other sexual functions.”

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When it comes to expectant mothers getting a vaccination, Liu said: “It is never too early to get vaccinated for the protection of the pregnant person. Pregnant patients are at higher risk of worse outcomes of COVID infection. Infections also jeopardize the health of the fetus. The vaccines are safe and effective for them and their fetuses. If I were pregnant, I would have gotten vaccinated already and I tell my patients who are pregnant to please, please get vaccinated.”