Just over 95% of the 9,891 people with COVID-19 who have been hospitalized in Colorado since mid-January were unvaccinated, according to data released by the state health department for the first time Monday.

The data, which further demonstrates the effectiveness of the shots, also shows that 78.7% of the 717 people with COVID-19 who have died in Colorado since April 1 had not received any doses of the three available vaccines.

“Vaccination is the best protection against COVID-19, including the delta variant,” a spokesperson with the Colorado Department of Public Health and Environment said in an email. “We encourage all eligible Coloradans to get vaccinated as soon as possible. It is the easiest way to protect our friends, families and communities and to return to the lives we love.”

The agency encourages anyone not fully vaccinated to continue wearing a mask, physically distancing, washing their hands and limiting gatherings.

Nationally and in Colorado, cases of the coronavirus are increasing, particularly in states with low vaccination rates such as Arkansas and Missouri, as the more-transmissible delta variant and other strains become more widespread.

Colorado has experienced a decline in the number of people getting vaccinated in recent weeks. About 62% of all eligible people — everyone 12 and older — are fully vaccinated.

And in Mesa County, which has become a hotspot in Colorado for the delta variant, 88% of the 481 people hospitalized for the virus and 92% of the 8,479 cases so far this year have been among individuals that have not yet received a COVID-19 shot.

Only 42% of that county’s residents are considered fully immunized against the coronavirus, according to Mesa County Public Health.

The hospitalization data provided by the state Department of Public Health and Environment is for the period Jan. 15 to July 10. Hospitalization data can lag for several days.

Of the nearly 10,000 Coloradans hospitalized with — but not necessarily for — COVID-19 during that period, just 4.7% were either fully or partially vaccinated at the time they tested positive for the virus and 95.3% had not received any doses, according to the state health department.

During the most recent week with data available, July 4 through 10, 188 of the 207 people hospitalized with COVID-19 — or 90.8% — were not known to have been vaccinated, according to the agency.

The death data provided by the health department is for the period of April 1 through July 3. Reporting of deaths to the state can be delayed by weeks, and in these cases, the causes of death have not all been reviewed yet, the agency said.

Since the beginning of the pandemic, 7,116 people have died directly due to the virus in Colorado, according to state data.