Dr. Anthony Fauci wasn’t at Donald Trump’s side for his daily coronavirus task force briefing on Tuesday. But Fauci’s aggressive and unpredictable media tour continued on Snapchat, where he’s appearing this week on Good Luck America, the platform’s daily political show, which is hosted by Peter Hamby.

In the interview, taped Tuesday and airing in episodes throughout the week, Fauci knocked down conspiracy theories about 5G networks weakening immune systems, said that individual states take the lead on COVID-19 testing, expressed worries about interstate travel, questioned Apple and Google’s contact tracing plans, and suggested that Major League Baseball could begin in July with player testing and without crowds. We’re posting Hamby’s full Q&A here, which has been lightly edited.

Vanity Fair: The first thing I want to ask you is this theory spreading around the internet that I’ve heard a lot lately, and it’s unfortunately pretty durable in the U.K. right now, that 5G towers are weakening the immune system and forcing people to get COVID-19. As an immunologist, can you say definitively that 5G is not getting people sick?

Dr. Anthony Fauci: Yeah. That’s easy. That’s thoroughly preposterous, untrue, and actually ridiculous. [laughs] Sorry. It’s a pretty simple answer. 5G doesn’t have any impact on the immune system. A lot of things do, but not that.

So what do you say to people who see these sorts of theories on the internet? Where should they go to check or debunk them?

You know, I’m not so sure that there’s a site that would debunk something as far out as that. But if they really want to learn about the immune system, there’s many approaches. If they, if they’re worried about the immune system and the relationship to COVID-19, and namely what’s going on right now, I would just click on the CDC website, cdc.gov, and then from there, you go to coronavirus.gov. And they could tell you all about the things that are relevant. Like why some people, like the elderly, and certain people who have underlying conditions that weaken their immune system, why they not only get infected the way everybody does, but they really have a poor outcome because their body is not able to fight off the virus very well. If you look at what’s going on in our own country and globally, generally, the people who really, really get into trouble are people who have underlying conditions. What we’re disturbingly starting to see now, which is really troublesome, is that the original cases from China made it seem that young people and healthy people get a mild illness. It goes away, no problem. Now we’re starting to see—it isn’t very common, but it is occurring enough to be concerning—that people who are younger are getting ill, and some of them are getting seriously ill, and even dying from this.

Are you seeing in the data from the United States that the rates of infection for young people are actually increasing from where they were a few weeks ago?

No. No. It’s not increasing. It’s steady. But young people, they get infected. It is more likely, if you’re young and healthy, that you may have what’s called an asymptomatic infection. You won’t know that you’re infected. But you still can inadvertently and innocently spread the virus to someone who is actually quite vulnerable. You know, your grandmother, grandfather. Your uncle who just finished chemotherapy for cancer. Or someone who has a compromised immune system. So even though there’s a slight risk compared to the risk among elderly and people who have underlying illnesses, there’s a slight risk of serious illness in the young, the risk of their spreading the infection is considerable.