Coronavirus cases have doubled in the past three weeks, with cases rising in 45 states. Ninety million Americans are still not vaccinated. The pandemic is nowhere near over. Now Dr. Anthony Fauci, the chief medical advisor to the President and the director of the National Institute of Allergy and Infectious Diseases, has a new warning. He appeared on MSNBC's Andrea Mitchell Reports. Read on for five life-saving pieces of advice, and to ensure your health and the health of others, don't miss these Sure Signs You Have "Long" COVID and May Not Even Know It.

"We have a Delta variant circulating and we're having, over the last couple of weeks, an increase in cases, as opposed to what we were seeing as a decrease in cases over the prior month or more," said Dr. Fauci when asked if the conversations regarding booster shots—are they needed or not?—was distracting right now. "When they hear that you might need a boost, they may get the impression that the vaccine is not effective. The requirement or not for a boost for a fully vaccinated person has absolutely nothing at all to do with the effectiveness of the vaccine. It has to do with the durability of the effectiveness. So people are saying, well, maybe these vaccines don't work if you're going to need a booster. No, not at all. These vaccines are highly, highly effective and safe. When you're talking about a boost, you're talking about how long that protection lasts."

"The children who are not able to get vaccinated because of their age should follow — their parents should follow with them — the guidelines of the CDC, that unvaccinated children of a certain age greater than 2 years old should be wearing masks, no doubt about that," said Dr. Fauci. "That's the way to protect them from getting infected, because, if they do, they can then spread the infection to someone else. So, the CDC guidelines for unvaccinated people, including children, are not changed at all."

"We are currently doing — we being the federal government, together in collaboration with the pharmaceutical companies — age de-escalation studies, namely, looking at the safety and the immunogenicity of vaccines in children from 12 to 9 years old, then from 9 to 6, then from 6 to 2 years old, and then, ultimately, from 6 months to 2 years old," he said. "Those data will likely be available by the end of the year. And then it will be up to the FDA to decide when they will make a recommendation that, in fact, this could be done, in the sense of vaccinating children of that age."

"I'm not so sure they're pushing for it," answered Fauci. "What they're doing is that they're looking at their data. They're looking at the data in Israel"—where booster shots are being administered to high-risk people—"and they're saying we want to be prepared and we might even actually recommend that. It's a good idea to get a third shot, namely a late booster compared to the prime boost that you get with the two dose vaccine regimen. People need to understand that pharmaceutical companies don't make the decisions. This becomes a regulatory issue with the FDA and a public health recommendation with the CDC and their advisory committee on immunization practices."

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Follow Fauci's fundamentals and help end this pandemic, no matter where you live—get vaccinated ASAP, if you're not, wear a face mask that fits snugly and is double layered, don't travel, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene, and to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.