While talk show host John Oliver has spoken about the big bad pharmaceutical industry in the past and tackled topics like marketing directly to doctors, a recent episode of his show Last Week Tonight saw him focusing on what he called one of humanity’s most incredible accomplishments: vaccines.

There’s been a major furore over a supposed link between vaccines and autism, which is connected to a debunked study by Andrew Wakefield, the discredited researcher whom Oliver has a title for (“the Lance Armstrong of doctors”). Misinformation from various sources like his work, actor Rob Schneider, and even internet memes can have a negative effect on vaccination rates, warned Oliver.

And this can lead to once-eliminated serious illnesses making a comeback, such as the measles outbreak currently seen among Minnesota’s Somali population.

“Despite their success, small groups are both sceptical and vocal about vaccines, which is nothing new,” he said. “But these days their voice has been amplified by the human megaphone that is the president of the United States.”

Oliver moved to a video clip from Donald Trump’s presidential campaign trail which had him saying that he supports vaccinations for children, but “I want smaller doses over a longer period of time because…you take this little beautiful baby and you pump...I mean it looks just like it’s meant for a horse, not for a child.”

Oliver also took on parents who support unconventional views about vaccines, explaining how sketchy this territory can get. For example, there are the slow-vaxxers who think that doctors should space out vaccinations for their children (like Trump does). Just because it may sound like a good idea doesn’t mean it is one. Oliver notes that it is actually “a middle ground between sense and nonsense.”

He agrees that vaccines in general can feel super-intimidating to most people.

“Vaccination can mean getting injected by a needle filled with science juice – although pretty much every medical practice sounds terrifying when you break it down like that.”

He explained how essential it is to have children vaccinated on schedule, citing an example about his infant son. “I’ve worried about his health, and I still worry about his health a lot,” he said. “And if I can resist the temptation to listen to the irrational shouting of my terrified lizard brain, then I believe that everyone can.”