Dr. Alana Biggers, MD, MPH, is an assistant professor of medicine and internist at the University of Illinois at Chicago Hospital. Hailing from Atlanta, Georgia, Biggers earned a master’s in public health with a focus in chronic disease epidemiology from Tulane University, attended medical school at UIC, then completed a residency in the greater Milwaukee area. She returned to Chicago in 2014, and now researches methods to reduce health disparities in underserved communities.
Biggers discussed the COVID-19 delta variant and the effectiveness of currently available vaccines with the Weekly. This interview has been edited for clarity and length.
What is the delta variant?
The delta variant is one of many variants of the coronavirus that causes COVID-19. Viruses get smarter over time and can mutate from their original form, so the delta variant is the fourth mutation. (Doctors use Greek letters to distinguish each variant.) That means we’ve already seen the alpha, beta, and gamma strains of the virus.
How is the delta variant distinct from earlier COVID-19 strains?
It is more contagious. The delta variant is about fifty percent stronger than the original alpha strain. With earlier strains, a person with an active infection could, on average, spread it to two people. But with the delta variant, a person can spread it to about five people. Over eighty percent of cases in the nation are now from the delta variant. It’s currently the predominant strain in the United States.
If you test positive for COVID-19, you likely will not be able to tell if you caught the delta variant or another strain. Studies show that while coughing and loss of smell may be less of an issue with the delta variant, other symptoms including fever, headache, runny nose, and sore throat are still common.
What should we do to protect ourselves from the delta variant?
You should wear a mask and socially distance yourself from others. Also, get vaccinated if it is available to you. Even if you do get sick, the vaccine helps protect you from serious illness and hospitalization.
How does the vaccine work?
There are two types of vaccines available for COVID-19. The Pfizer and Moderna vaccines are both mRNA vaccines; mRNA is genetic material that teaches your body how to make proteins. We inject a small amount of mRNA into your body for your cells to make copies of the spike protein that is found on the coronavirus. Your body will recognize these proteins are foreign and rev up your immune system to fight them off. It is important to add that your cells will break down and get rid of this mRNA as soon as it is used.
The Johnson & Johnson vaccine uses a different approach. Rather than mRNA, it uses a harmless, inactive version of the common cold virus to carry information about the coronavirus spike protein into your cells. As before, your body will then create spike proteins, recognize them as foreign, and make antibodies to get rid of them.
Both methods will protect you if exposed to COVID-19 in the future. Your body will remember that those spike proteins don’t belong there and will already know how to fight them off.
Why do some people report feeling sick as a side effect of the vaccine if it does not contain the COVID-19 virus?
Many people won’t experience side effects from the vaccine, but some may have flu-like symptoms that will clear up within thirty-six and seventy-two hours. This is your body’s response when creating the antibodies. You are not getting COVID-19 or the flu, because you are not being injected with either virus. It’s the body’s way of reacting to something foreign being there, and trying to fight it off. Actually, it’s a sign that your immune system is working the way it is supposed to.
If the vaccine was created to target the earlier COVID-19 strains, how can it be effective against the delta variant?
The vaccine provides you with a boost in immunity by allowing your body to develop antibodies to fight COVID-19. The components of the original virus strain and the delta variant are the same, so your body will still recognize the virus and have that antibody response.
Some people are hesitant about getting the vaccine. How do we know that it is safe?
I understand the hesitancy. But I understand the science, too. The vaccine development wasn’t rushed, and it is not some type of mystery or experimentation on the general public. The mRNA vaccine technology, in particular, has been around for years, but there wasn’t an urgent need for a coronavirus vaccine until the pandemic hit. When it did, infectious-disease researchers got an influx of money and resources to carry forth in developing the vaccine quickly and safely.
All three COVID vaccinations are safe and effective and are constantly monitored by the CDC and the FDA for serious adverse events. Over 386 million doses have been given with very few serious side effects reported thus far.
What is a breakthrough case?
Breakthrough cases are COVID-19 infections that occur even though a person has been vaccinated. This happens when the antibody response your body has from getting the vaccine is not strong enough to kill off the virus. Breakthrough cases are more frequent now because the delta variant is more contagious, so the vaccine may be less effective against this strain.
What is a booster shot and why do we need them?
The effectiveness of the vaccine wanes over time. The Pfizer and Moderna vaccines are over ninety percent effective against infection in the first two months, but drop to about sixty percent after four to five months. Booster shots are recommended to give people a boost in their immunity against COVID-19. This will allow you to have a stronger immune response if you are exposed to the virus.
The Biden administration recently announced that booster shots will be ready toward the end of September. [Editor’s note: on September 22, the FDA approved Pfizer booster shots for adults aged sixty-five and older, as well as younger adults who have certain health conditions and people who work in front-line jobs.]
When will life go back to normal?
I wish I knew—if only I had a crystal ball! The Spanish flu pandemic of 1918 lasted for two years. If we are not able to get the COVID-19 virus under control, we may have to get a COVID-19 vaccine every year like we do with the flu shot. But we’re still within the first year of understanding the vaccine and its effectiveness. Regardless, the quickest way back to normalcy is for everyone to get vaccinated, wear masks, and socially distance themselves.
Katrina Miller is a University of Chicago physics PhD student and freelance science journalist. This is her first article for the Weekly.