HERSHEY, Pa. (WHTM) – Certain mouthwashes may help stop the spread of coronavirus. That’s according to new research from Penn State College of Medicine.

The study found several mouthwashes could be effective at inactivating more than 99.9% of human coronaviruses after just 30 seconds, but there are some caveats.

“We’re not curing this disease. I mean, the virus is still inside your cell. Our goal, our hope is that the virus that’s sitting there on your saliva, ready to be aspirated out as you talk, it can kill that. It’s not going to go down into the cells and get rid of the cells or the virus that’s already there,” said Dr. Craig Meyers, Professor of Microbiology and Immunology and Obstetrics and Gynecology.

The researchers, led by Dr. Meyers, used a strain of human coronavirus, genetically similar to SARS-CoV-2, which causes COVID-19.

When treated with several different mouthwashes in a lab, they found they inactivated more than 99.9% of human coronavirus after 30 seconds. That same percent effectiveness was found with a 1% solution of baby shampoo, used to rinse sinuses after two minutes.

“There’s tons and tons of drugs out there, that we test in the laboratory. They look great in the laboratory. We go to humans, nothing happens,” said Dr. Meyers.

On the other side of that coin.

“If anything this simple could be a help, you know why not, try to follow it up?” said Dr. Meyers.

According to Penn State College of Medicine, about a dozen clinical trials are already underway. As for how long the mouthwash effectiveness could last?

“Will it be 12 hours, will it be 24 hours, 6 hours? And that’s one of the first goals of what we’re planning to do in our clinical trial,” said Dr. Meyers.

The researchers say hydrogen peroxide-based mouthwashes had little effect, but brands like Listerine and Crest “pro-health” were effective.