How effective is the COVID-19 vaccine?

There are multiple COVID vaccines at various stages of the development, approval and distribution process. The clinical trials for the Pfizer vaccine showed a 95% efficacy rate and 94% with the Moderna vaccine in preventing symptomatic COVID. That means the rate of catching COVID in vaccinated participants was only 5-6% of the rate seen in those who received placebo. There is still a small chance of infection post-vaccination. Masks and social distancing will be with us for some time to come.

Research is still being done to measure the impact on transmission—whether someone vaccinated can pass the infection on to someone else. Virtually all other vaccines both protect against getting the disease and reducing transmission, and it is our hope that these vaccines follow that pattern. As with other vaccines, the more people who get immunized, the greater the community-wide protection against the disease.

The Janssen (Johnson & Johnson) vaccine—authorized for use as a single dose rather than two doses—has been shown in clinical trials including over 40,000 subjects to have a 66% efficacy rate in preventing symptomatic COVID. It has a 93% efficacy rate in preventing hospitalization >14 days after vaccination. No hospitalizations occurred in vaccinated subjects >28 days after vaccination. Seven COVID-related deaths occurred in the placebo group and none in the vaccinated group. This means that those who are vaccinated, if they do get COVID, are extremely unlikely to get a severe enough illness to require hospitalization or become fatal.

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1. How effective is the COVID-19 vaccine?
2. Is the vaccine safe?
3. What are the side effects from the vaccine?
4. What adverse reactions were reported for the vaccine?
5. Will the vaccine give me COVID?
6. How many doses do I need?
7. Who will get the vaccine first?
8. How were the phases decided? Can I get vaccinated sooner?
9. How do I know if a message or email offering vaccination options is legitimate?
10. When will I get vaccinated?
11. Who should get the vaccine?
12. If I had COVID, should I still get vaccinated?
13. Do I get to choose which vaccine I get?
14. Once I get the vaccine, can I stop wearing a mask?
15. How soon can we get back to pre-pandemic activities?
16. How does the vaccine work?
17. Does the vaccine change my DNA or implant a chip?
18. What is in the vaccine?