DENVER (KDVR) — The risk of death from COVID-19 remains much lower for those who are fully vaccinated, but health experts still encourage booster shots for many.

According to the Colorado Department of Public Health and Environment, 189 unvaccinated people died from COVID-19 in August, compared to 60 vaccinated individuals. The median age among vaccinated people who died from the virus was 81 years old and 75 for the unvaccinated deaths.

Serious breakthrough cases are no longer rare but remain uncommon, according to Dr. Michelle Barron, senior medical director of infection prevention with UCHealth.

“I’d say two-thirds of our hospitalizations of individuals who are fully vaccinated are over the age of 60 and have underlying co-morbidities; whether it’s diabetes or obesity. The age is really an important distinction,” said Barron.

Barron said the remainder of vaccinated, hospitalized patients are not necessarily young, and typically have underlying health conditions. She said the trends they’re seeing highlight the importance of booster shots for vulnerable populations.

“To have that extra protection — nothing of course is 100% but certainly, looking at the numbers it suggests that we could potentially. prevent that cohort from being hospitalized,” Barron said.

Colorado has administered nearly 270,000 additional COVID-19 vaccine doses to those who are eligible.