(CNN) -- The U.S. has reached another grim COVID-19 milestone. According to data from Johns Hopkins University, more than 40 million people in the country have had COVID-19.
There's been more than 4 million cases reported in the last four weeks alone.
This number represents officially-reported positive test results. Many experts believe the real number of infections is much larger.
According to the data, more than 649,000 Americans have died since the pandemic started.
Dr. Anthony Fauci, the expert leading the coronavirus response for the White House says he's still optimistic Pfizer booster shots will be available September 20.
Moderna may take a bit longer and Johnson and Johnson's booster is still being researched.