Health experts say the Biden administration's goal to get 70% of U.S. adults vaccinated with at least one shot of a COVID-19 vaccine by July 4 is unlikely.

With the nation at a little more than 65%, they say the weekly vaccination rate will not make it possible to achieve the goal.

In 16 states and D.C., 70% of adults have received one dose. Alabama, Louisiana, Mississippi and Wyoming are among the slowest to vaccinate.

But medical experts are less worried about hitting 70% by July 4.

"I think as a practical matter from a public health standpoint, it's not going to have an impact whether we hit 68% or 70%," says former Food and Drug Administration Commissioner Dr. Scott Gottlieb. "Now we need to think about trying to push out the vaccine into community sites where people could get it delivered to them through a trusted intermediary. That's going to be doctors, officers, schools, places of employment."

Health experts are more worried about where the nation goes from here, especially as the Delta variant continues to spread.

"I anticipate that will be the predominant variant in the months ahead," says Centers for Disease Control and Prevention Director Dr. Rochelle Walensky.

The Delta variant is already taking its toll in Missouri.