Community health workers are trained in vaccination techniques for the inhalable COVID-19 booster doses on November 16, 2022 in Shijingshan district, Beijing. Photo: IC

At least 11 districts in Beijing including Chaoyang, Xicheng and Haidian opened appointments to the public for inoculations using China's first aerosolized adenovirus vector vaccine for booster doses starting on Tuesday. 

At a press conference on Wednesday, the Chaoyang district government said that residents can make phone appointments for free, single-dose inhalable boosters, and encouraged those who have not yet been inoculated, especially the elderly, to get vaccinated as early as possible.

Observers said that offering the inhalable vaccine as a booster is expected to be an effective strategy in relieving the recent flare-ups in China, especially in Chaoyang district, the most populous area of the capital, which recorded the most COVID-19 cases during the latest outbreak.

At present, the single-dose aerosolized adenovirus vector vaccine is only provided as a booster for those above 18 who have completed either two shots of inactivated vaccines or one shot of CanSinoBIO's adenovirus type-5 vector-based vaccine. 

Some other cities including Shanghai, Hangzhou and Tianjin previously started to offer the inhalable vaccines as boosters, as COVID-19 flare-ups caused by highly transmissible Omicron variants have been reported across the country.

The Global Times learned from insiders that the inhaled vaccine is not available for those who have completed three doses of the inactivated vaccines, as China has not yet officially rolled out mass vaccination of the fourth dose.

"A large part of the Chinese population has been completely vaccinated for more than half a year. It is hard for them to retain a high immunity level against various mutant strains. It is recommended to consider carrying out a fourth dose in order to beef up the immune level," Tao Lina, a Shanghai-based medical observer, told the Global Times on Wednesday.

The vaccine is administered by atomizing it into tiny particles with an atomizer and sipping it by mouth. 

Some people who have been vaccinated described the process as being like sipping a cup of bubble tea and it even tastes a bit sweet in previous interviews with the Global Times. 

The public, especially those who are sensitive to needles, would be more receptive to an inhaled vaccine, given its painless and relaxed experience, said Tao.

Research by CanSinoBIO in October showed that a heterologous booster with inhaled adenovirus vector vaccine can generate more neutralizing antibodies against different COVID-19 variants.

This is the world's first aerosolized COVID-19 vaccine, and it was approved by Chinese national authorities for emergency use as a booster in September, according to the developer.