Effectiveness of COVID-19 Vaccines from China and Russia Questioned

Scientists are questioning the effectiveness of vaccines made in China and Russia due to their dependence on the adenovirus, a common cold virus that most people have already encountered. Both the Russian and Chinese vaccines use a modified adenovirus to transmit genes from the novel coronavirus into human cells. Because many individuals already have immunity to the adenovirus, the immune system may attack it instead of the novel coronavirus, reducing efficacy. Read more here.