In accordance with new Centers for Disease Control (CDC) guidelines, HSHS Medical Group now offers a third dose of mRNA COVID vaccines (Moderna and Pfizer) to patients whose immune systems are moderately or severely compromised. An additional dose of mRNA COVID vaccine can be given at least 28 days after a second dose. While studies are underway for a Johnson and Johnson vaccine booster, a second dose of Johnson and Johnson is not recommended at this time.

Who should get a third dose of COVID vaccine?

Talk to your doctor about whether a third dose of the mRNA COVID vaccine is appropriate for you. Guidelines include immunocompromised people who have:

•    Been receiving active cancer treatment for tumors or cancers of the blood
•    Received an organ transplant and are taking medicine to suppress the immune system
•    Received a stem cell transplant within the last 2 years or are taking medicine to suppress the immune system
•    Moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome)
•    Advanced or untreated HIV infection
•    Active treatment with high-dose corticosteroids or other drugs that may suppress your immune response

Can I get a third dose if I’m not immunocompromised?

HSHS intends to make third doses available to non-immunocompromised patients at a later date in accordance with recent guidelines announced by President Biden. We will communicate with our patients and the public when this becomes available. “The rollout of third doses will be similar to the first round of vaccinations in December and January, with vaccines triaged first to those with a highest instance of exposure, such as the immunocompromised,” said James Bock, MD, HSHS Medical Group chief physician executive. “Thankfully the mRNA vaccines are more widely available now.”

Can I mix and match the vaccine brands?

As recommended by the CDC, HSHS will administer the same brand vaccine that patients received for their first two doses as long as it is available. The CDC says it is also acceptable to receive a different brand if your first brand is not an option.

What symptoms should I expect from a third dose?

“Research has shown the reactions after a third dose of mRNA vaccine are very similar to second dose reactions,” said Bock. “Most reported symptoms after the third dose are mild to moderate and could include pain at the injection site and fatigue.” 

Why are third doses needed?

“The first two doses of vaccine offer protection from early versions of COVID,” said Marc Shelton, MD, FACC, HSHS senior vice president and chief clinical officer. “If it hadn’t been for the Delta variant, we likely wouldn’t need a booster for COVID this fall. Fortunately, the data released from Pfizer in the last couple days indicates that a third dose is effective against Delta. Just like influenza, we need booster shots because COVID is so likely to mutate. Companies like Pfizer and Moderna will continue to study and adjust vaccines to address the latest mutation.”

Do breakthrough cases mean the vaccine isn’t working?

Questions abound when a vaccinated person still gets infected with COVID. Shelton explained the biology behind breakthrough cases: “A vaccine encourages your body to produce antibodies, which are protein molecules in the bloodstream. If those antibodies run into the virus and match it, they have a chemical way to kill it.

Following the first and second shot of COVID vaccines, antibodies increase. Over time, the level of antibodies in the blood typically goes down if there are no events that cause the body to need more. When they go down, a person becomes more susceptible to infection. The normal lifespan of a protein antibody is several months, according to Shelton.

“If you’ve run out of antibodies in the blood stream and later you get a highly infectious Delta variant and the body doesn’t have enough antibodies to kill all this virus at once, the cells start producing more antibodies immediately. You’ll get the infection and experience some symptoms while your body catches up by producing more antibodies. However, breakthrough case symptoms are usually milder and less likely to kill you. You may be a little infectious, though not as much as someone who is unvaccinated. Hence the need for universal masking, even among those fully vaccinated,” said Shelton.

Is there a rise in pediatric COVID cases?

Thirty percent of new COVID cases over the past month have been individuals younger than 20, the least vaccinated part of our community. “The good news is, unlike Florida and parts of Texas, most of our pediatric cases have been fairly mild,” says Shelton. “HSHS has not had significant pediatric hospital admissions yet.”

Shelton hopes the community will pull together to keep everyone as healthy as possible: “We encourage everyone to mask, quarantine when necessary, be careful in schools and get vaccinated.”

Where can I get the vaccine?

HSHS Medical Group offers COVID-19 vaccines to community members who are 12 years and older. A parent or guardian must accompany those age 12-17 when they receive the vaccine, and Pfizer is the only type of COVID-19 vaccine available to those in that 12-17 age range. 

HSHS Medical Group offers COVID-19 vaccines and testing to their patients at drive-thru locations and some primary care clinics. 

View information on our drive-thru locations and hours.

Find an HSHS vaccine clinic near you.

Media Contact

Lori Harlan

Divisional Director of Marketing
HSHS Medical Group
Office: (217) 321-9292
Cell: (217) 321-9292

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