Cases and hospitalizations are continuing to spike among the unvaccinated in Tennessee. And now, Republican leadership in the state legislature is urging more residents to get vaccinated against COVID-19.

On Tuesday, 16 state senators signed a letter touting the benefits of getting the shots, explaining some of the science behind mRNA and warning about the dangers of not being inoculated. The letter says “vaccines have been saving lives for over a century,” and “virtually all of those currently hospitalized with COVID-19 have not been vaccinated.”

By the estimation of the Tennessee Department of Health, 97% of hospitalizations are among the unvaccinated. And hospitalizations for COVID-19 have nearly quadrupled since July 4. Among Tennessee patients in ICUs is conservative radio talk show host Phil Valentine, who was unvaccinated and now says through family members that he regrets leading listeners astray.

“Unfortunately, efforts to get more people vaccinated have been hampered by politicization of COVID-19. This should not be political,” the senators write. “Every life lost to this virus is tragic. The COVID-19 vaccines save lives.”

The joint letter, signed by Senate Speaker (and pharmacist by trade) Randy McNally, comes after the state’s top vaccine official was fired amid the debate about the health department promoting vaccinations to teens. The signatures of state senators who grilled health department officials — including Sens. Kerry Roberts, Janice Bowling and Mark Pody — are conspicuously absent. In all, 11 GOP senators chose not to sign.

Just 39% of Tennesseans are fully vaccinated, and the pace has slowed to a crawl. But, in the last few weeks, the state has seen a slight surge in uptake as the delta variant brings renewed concerns and a new wave of cases.

WPLN’s Marianna Bacallao contributed to this report.