WATCH: Walensky says country is still in ‘complicated stage’ of pandemic

As the country opens up vaccines to anyone 16 and over the Director of the Centers for Disease Control and Prevention warns that we are still in a “complicated stage” with coronavirus.

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“More people in the United States are being vaccinated every single day at an accelerated pace,” said Dr. Rochelle Walensky during the White House COVID-19 Task Force briefing on Monday.

“On the other hand, cases and hospitalizations are increasing in some areas of the country, and cases among younger people who have not yet been vaccinated are also increasing.”

This also comes after health officials said Sunday the country reached the milestone of having 50 percent of adults at least partially vaccinated.

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Monday also marks the expansion of the White House’s federal retail pharmacy program.

Senior adviser Andy Slavitt says more than 90 percent of Americans live within 5 miles of a vaccination site.

“We know these vaccines work extraordinarily well as prevention interventions, however, they take some time to kick in somewhere in the two to six week mark,” said Walensky.

“So if we have a lot of circulating virus today, the vaccines will work in a month, but they may not work today. So we need to continue to keep the prevention measures up to prevent ongoing cases today.”