A COVID-19 vaccine that has been developed in China appears to be safe and effective.br According to UPI, the vaccine successfully induced an immune response against the virus in a small trial.br 95 of trial participants who received a high dose of the vaccine and 91 of those given a lower dose had immune responses.br The study participants developed the immune response within 28 days of receiving the vaccination.br The vaccine is based on a weakened human common cold virus, or adenovirus.br The virus can infect human cells but is incapable of causing disease.