The states that saw the increases were Alaska, Alabama, Arkansas, Arizona, Florida, Georgia, Hawaii, Mississippi, Montana, North Carolina, Oklahoma, Oregon, South Carolina, South Dakota, Texas, Utah and Vermont, according to the analysis of state-released data compiled by the COVID Tracking Project.
Seventeen states were also showing an increase in the rate of positivity, a measure of how many tests are positive for COVID-19 compared to the amount of tests run.
Deaths also are on an upward trend in 13 states and Washington, D.C., though in many of those states, the numbers are very small and have been fluctuating.
ABC News tracked the trends over two weeks using a linear regression trend line of a seven-day moving average.
Arizona is the only state to see an increase in hospitalizations, deaths and rate of positivity. However, seven states are experiencing two of those trends.
The upward trends in those states have sparked talk of a second wave, but experts say the U.S. is still in its first.
"We are in the first wave, but we are in the second inning of a nine-inning game," Dr. Michael Osterholm, an epidemiologist at the University of Minnesota, told ABC News earlier this week.
Just this week, Florida shattered its record-high one-day increase of 3,822 cases on Friday after setting a previous daily-increase record of coronavirus cases Thursday with 3,207.