Transcript for By the Numbers: Is protective or herd immunity possible?
Now the race for Kobe nineteen vaccine in key questions scientists want to answer what's the length and effectiveness of protective immunity. And vaccine work here's the latest research by the numbers. A potential cove in nineteen vaccine is unlikely to be more than 75%. Effective according to leading infectious disease doctor Anthony vouching. The measles vaccine by comparison. Has about 98%. Effective. No one issue is that antibodies not to protect us from cove in nineteen can disappear in only two to three months that's according to a new study out of China. Similarly the antibodies that we produce after catching the common cold which is also caused by a type of corona virus they last only three to six months which is why. Colds or are so common. Some had hope that we can develop so called herd or population line immunity to cope in nineteen but. Seventy to 90% of US population would need to develop antibodies in order to achieve that according to Johns Hopkins. Which enables up to 300 million Americans. We've. Only about three million Americans testing positive for the virus disease. Are nowhere near that.
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