A woman has just received a shot at the doctor's office

December 14, 2020

After nine months in a pandemic, the news of a COVID-19 vaccine brings welcomed relief and hope. But, as you make decisions for yourself or your family, the news can feel overwhelming. Memorial Hermann is here to help. Here’s what you need to know about the COVID-19 vaccine.

Q. How do vaccines work?

A. They train the body’s immune system to recognize and attack viruses and bacteria. Vaccines have saved many lives once threatened by flu, diphtheria, tetanus, pertussis and measles.

Q. How does the COVID-19 vaccine compare to others we know such as the flu vaccine?

A. Traditional flu, measles, diphtheria and polio vaccines deliver a weakened dose of the disease which alerts our immune system to fight the enemy.

The COVID-19 vaccine is different. Two leading COVID-19 contenders—from Moderna and Pfizer/BioNTech SE—use a new high-tech approach, known as mRNA, which stands for messenger ribonucleic acid.

These molecular couriers ship COVID-19’s genetic coding for a protein directly to cells. Our body recognizes that the protein is foreign and starts making antibodies against it to protect us. Neither the molecular courier, nor the COVID-19 genetic material for the protein, alter your DNA; nor do they enter the part of the cell where your DNA is stored.

The Pfizer and Moderna vaccines have unusually high efficacy rates of 95% and 94%, respectively. That means those vaccinated were protected 95% and 94% of the time, versus the placebo group.

Q. What is the timeline for access to COVID-19 vaccines?

A. The U.S. Food and Drug Administration has approved the Pfizer vaccine, and Moderna is expected to follow soon after. We will see additional vaccines before the FDA as phase 3 clinical trials are completed.

Those at greatest risk of catching the virus or dying from COVID-19 will be vaccinated first. They include hospital doctors, nurses and respiratory therapists who care for COVID-19 patients. Nursing home staff and residents also will be at the front of the line. So will Emergency Medical Services and hospice care workers.

Teachers, school nurses and other frontline workers are expected to be next in line.

Over the new few months, as production continues to ramp up, vaccine will be made available to Americans with a higher risk of complications from COVID-19, and then the general public. Testing thus far has focused on adults, so further testing will be needed before children and pregnant women are vaccinated. 

Q. What is the process for getting vaccinated?

A. Hospitals, doctors’ offices, retail pharmacies and federally qualified health centers are anticipated to give the first available vaccines in two doses: an initial vaccination followed by a booster shot of the same vaccine three to four weeks later.

Q. What are potential side effects of the vaccine?

A. Some people report getting a headache or fever when getting a vaccine. According to the CDC, you should know that side effects like this are a sign that the immune system is working by building protection from the disease.

Learn more about COVID-19 and the COVID-19 vaccine »

The information in this article was accurate as of December 14, 2020.

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