According to the CDC, more than 130 million, or 50% of Americans have received at least one vaccine dose of the country's total adult population.

Also, about 84 million, or 32% of Americans have been fully vaccinated of the country's total adult population.

CDC considers Americans fully vaccinated two weeks after they receive Johnson & Johnson's single-dose vaccine or their second dose of Pfizer/BioNTech's or Moderna's two-dose vaccines.

Data shows more than 78% of Americans ages 75 and older have received at least one dose of a Covid-19 vaccine, while only about 25% of adults ages 18 to 29 have received at least one vaccine dose.

Vaccinations rates are lower among young adults in part because states previously applied age restrictions on vaccine appointments due to limited vaccine supply.

As of Monday, however, all American adults are eligible to sign up for Covid-19 vaccination appointments.

On Monday, Jeff Zients, the White House's coronavirus response coordinator, said the United States is on pace to meet President Biden's goal of administering 200 million Covid-19 vaccine doses within his first 100 days in office, which will be April 30.

Although the pace of vaccinations has increased, CDC Director Rochelle Walensky during a White House Covid-19 briefing on Friday said new coronavirus cases and hospitalizations are continuing to rise.

Average daily number of newly reported coronavirus cases over the past week was 67,308—up by 5% compared with the average from two weeks ago.

Data shows that 45,643 Americans with Covid-19 were hospitalized on Sunday—up by 11% compared with the average from two weeks ago.

Why are cases rising despite vaccine efforts?

Walensky said this month that the increase in COVID cases is due in part because younger adults have largely not been vaccinated. 

Younger adults were generally more restricted in being able to get vaccinated, and during this time more highly contagious variants have been spreading.

Paul Offit, a physician at Children's Hospital of Philadelphia, said he believes more young Americans are being hospitalized with Covid-19 because "they're getting infected more frequently because of the contagiousness of the virus."

Even as cases and hospitalizations are on the rise, there has been an 8% decline in deaths from the average two weeks ago. Read the full article from Advisory Board here.