Are certain vaccines more effective than others?

To measure how well a vaccine works in a clinical trial, the Food and Drug Administration (FDA) first looks at the number of people who fell ill with the disease. Then the agency compares whether they received the vaccine or the placebo (a harmless, inactive substance that looks identical to the vaccine being tested). If a greater share of those who are sick received the placebo instead of the vaccine, then the vaccine has met an acceptable efficacy standard.

Learn more about this process here.

Covid-19 vaccines currently authorized in the United States demonstrated extremely high efficacy in clinical trials. The Pfizer and Moderna vaccines had efficacy rates of 95 percent and 94.1 percent, respectively. The Johnson & Johnson vaccine, meanwhile,  was 85 percent effective in preventing severe disease across all regions studied, and showed protection against COVID-19 related hospitalization and death, beginning 28 days after vaccination.

Bottom Line: People should accept the first vaccine that becomes available to them in their area.

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Adhere To CDC Guidelines If you test positive for Covid-19, the following steps -- outlined by the Centers for Disease Control and Prevention (CDC) -- will help you care for yourself and protect others: Alert close contacts. Tell anyone you have recently come into contact with that you have Covid-19, so they can take the necessary precautions and prevent further spread. If you have concerns about confidentiality, especially in the workplace, check with your employer. Many can notify others…
Where should I go for trusted and up-to-date information on Covid-19 vaccines?
The Centers for Disease Control and Prevention (CDC) has great information on the Covid-19 vaccines, including a FAQ page. Another CDC resource will direct you to state Department of Health websites. Those sites will help you determine when you can get the vaccine in your area.
I'm young and healthy. Should I get vaccinated?
While not considered to be at high risk for severe complications from Covid-19, serious cases do occur among younger, healthier people. The Centers for Disease Control and Prevention (CDC) also warns of the potential long-term health effects of Covid-19 infection, even for those who experienced mild illness.