Inhaled COVID Vaccine Shows Promise in Animal Trials

TUESDAY, July 13, 2021 (HealthDay News) -- Breathing in protection: Scientists say an experimental inhaled COVID-19 vaccine shows promise in animal tests.

"The currently available vaccines against COVID-19 are very successful, but the majority of the world's population is still unvaccinated and there is a critical need for more vaccines that are easy to use and effective at stopping disease and transmission," said study co-leader Dr. Paul McCray. He's professor of pediatrics-pulmonary medicine, microbiology and immunology at the University of Iowa, in Iowa City.

"If this new COVID-19 vaccine proves effective in people, it may help block SARS-CoV-2 transmission and help control the COVID-19 pandemic," McCray added in a university news release.

The single-dose inhaled vaccine is similar to those commonly used to protect people against seasonal flu. It uses a harmless parainfluenza virus 5 (PIV5) to deliver the SARS-CoV-2 spike protein into cells, to trigger an immune response against COVID-19 infection.

PIV5 is related to common cold viruses and easily infects people without causing significant illness, the researchers explained.

Importantly, the vaccine can be stored at normal refrigerator temperatures for up to at least three months, the study authors noted.

In mice, the vaccine prompted a localized immune response that involved antibodies and cellular immunity, and provided complete protection against deadly doses of SARS-CoV-2. In ferrets, the vaccine prevented infection and disease, and appeared to block transmission of the coronavirus from infected ferrets to unprotected and uninfected ferrets in the same cage.

However, animal research doesn't always pan out in humans.

The study was published July 2 in the journal Science Advances.

Study co-leader Biao He said, "We have been developing this vaccine platform for more than 20 years, and we began working on new vaccine formulations to combat COVID-19 during the early days of the pandemic." He is a professor in the University of Georgia's department of infectious diseases, College of Veterinary Medicine.

"Our preclinical data show that this vaccine not only protects against infection, but also significantly reduces the chances of transmission," he noted.

More information

The U.S. Centers for Disease Control and Prevention has more on COVID-19 vaccines.

SOURCE: University of Iowa, news release, July 8, 2021