China announced Wednesday that it has started giving its citizens a COVID booster that can be inhaled through the mouth.

The oral vaccine was distributed in Shanghai. A video appeared on Chinese state media, showing people holding a translucent white cup with a short nozzle to their mouths. Text accompanying the video said a person slowly inhaled the mist, held his breath for five seconds and was finished within 20 seconds, the Associated Press reported.

Advantages to an inhaled vaccine could include appealing to someone afraid of needles and the concept of priming the area of the body where the virus often enters.

Dr. Vineeta Bal, an immunologist in India, said large droplets would prime the mouth and throat. Small droplets would travel further into the body, the AP reported.

The vaccine was developed by Cansino Biologics, a Chinese biopharmaceutical company, and is an aerosol version of the company's one-shot adenovirus vaccine. It was approved in September by Chinese regulators after completing trials in China, Hungary, Pakistan, Malaysia, Argentina and Mexico, the AP reported.

It was offered as a booster dose for people who had already received initial vaccines, according to an announcement posted on an official city social media account, the AP said.

An earlier nasal vaccine, developed in the United States, has been approved by regulators in India, but not distributed yet. It is licensed to Indian vaccine maker Bharat Biotech, the AP reported.

Other nasal vaccines are being tested globally, according to the World Health Organization.