Can you transmit COVID-19 even after vaccination? CU Boulder conducting new study

BOULDER, Colo. (KRDO) -- A new study at CU Boulder seeks to better understand COVID-19 transmission after vaccination.

This comes as Colorado considers further easing COVID-19 restrictions before the end of April.

According to CU Boulder researchers, reopening the state largely depends on vaccine efficacy. This means it's not just about protecting those who are already vaccinated from the virus, but preventing person-to-person transmission as well.

"We are pretty clear now that it will be very effective at preventing you from becoming sick," Professor Christopher DeSouza, said. "But, the big questions is whether it prevents transmission."

DeSouza is the Co-Principal Investigator for the study. CU Boulder is the first among 21 colleges in the U.S. that are participating in the trial, led by the federally funded COVID-19 Prevention Network.

"If you’re vaccinated and you do become exposed, once again to the virus, does being vaccinated prevent you from transmitting the virus to someone else?" 

At least 700 students from the college will participate in the study of more than 12,000 nationwide. CU Boulder senior Chase Willie received his first dose of the Moderna vaccine last Thursday.

"I kind of found that as an opportunity to be a part of a study that's actually making a big impact in the world," Willie said.

 He said he's hopeful the study's findings will help in the transition back to in-person learning this fall.

"A lot of our classes are going back in person, and I feel like people are having to re-adapt to that college experience."

Over the next five months, participants and their close contacts will be monitored for any signs of the virus through regular testing.

"This ties into a lot of the follow up questions that are important now regarding the vaccine," DeSouza said.

He said this includes discussions regarding how quickly COVID-19 safety restrictions should be lifted at the state and local level, as well as how soon vaccinated individuals should relax mask wearing or social distancing.

"It will absolutely determine whether those types of restrictions can be relaxed or relaxed in a safe way."

The study focuses on the Moderna vaccine. However, researchers said they're confident the results will also apply to other mRNA vaccines, like Pfizer. Results are expected to be finalized this fall.