A woman experiences an inhaled COVID-19 booster vaccination with purified water at an epxo in Haikou, Hainan province, in this Nov 12, 2021 file photo. Photo/VCG

Inhaled COVID-19 booster vaccinations were made available in Shanghai on Wednesday. Eligible residents can register through the health app jiankangyun to make reservations. The booster shot for free.

The vaccine is an adenovirus type-5 vector-based COVID-19 vaccine administered via oral inhalation. People above 18 years old who have been completely vaccinated for at least six months can opt to have the inhaled booster vaccination.

Authorities reminded the public that those who are allergic to components of the vaccine or have serious allergies to vaccines are not suitable for the inhalable booster. People with epilepsy that is not under control, other progressive neurological diseases, and Guillain-barre syndrome are also not suitable for the vaccination.

Pregnant women and people who have fever, acute illness, ongoing chronic diseases or serious chronic diseases that are not under control should not take the booster shot.