DALLAS — Staying on schedule with the COVID-19 vaccine can feel like chasing a moving target.
Rules and recommendations for the shot series changed over the last two years as studies revealed the efficacy of different vaccines, new vaccine recipes were released, and federal regulators granted different age groups access to the jabs.
The new bivalent booster, designed to create antibodies against both the original COVID-19 strain and the omicron variant, is now available to adults and kids 6 months and older, although people’s eligibility for this updated dose depends on which vaccinations they’ve already had and when they got their last shot.
COVID-19 cases are once again rising in North Texas, spurred by the highly contagious omicron subvariants B.Q.1, B.Q.1.1 and XBB, alongside high rates of the flu and respiratory syncytial virus, or RSV. Staying on top of the most recent vaccination schedule is still critical to mitigating the virus’ impact, doctors say.
“I think there’s some degree of vaccine fatigue among everyone, and the novelty with the COVID vaccine has worn off. People may not be necessarily paying attention to what the most current recommendation is,” said Dr. Minji Kang, assistant professor in the Division of Infectious Diseases and Geographic Medicine at UT Southwestern Medical Center.
Public health experts expect the coronavirus to become more seasonal in coming years, similar to how flu cases in the U.S. tend to pick up in the winter and decline in the spring. That change could allow for a more predictable vaccine timeline, said Dr. Pedro Piedra, professor of molecular virology and microbiology and of pediatrics at Baylor College of Medicine.
“Time will tell, but I think, ideally, we would like to be able to have something kind of like the flu, where we have an annual vaccination campaign and we have an updated vaccine. How that might look might change from year to year,” Piedra said.
Because COVID-19 is so new, it will likely take some time before updated vaccines are released on a regular schedule. In the meantime, here’s what you need to know about the current COVID-19 vaccine recommendations and when they might change:
The initial vaccine series
Vaccines that combat the original COVID-19 strain have been available for different age groups for either months or years. Still, only about 63% of Texans have completed the initial vaccine series, according to Department of State Health Services data.
The U.S. Food and Drug Administration has authorized four COVID-19 vaccines: Pfizer-BioNTech, Moderna, Novavax and Johnson & Johnson’s Janssen vaccine. However, Johnson & Johnson’s vaccine is only authorized in certain situations.
—Pfizer-BioNTech: Adults and children 5 and older receive the primary series of the Pfizer vaccine in two doses given three to eight weeks apart. The primary series for children between the ages of 6 months and 4 years is given in three doses. The second dose is given three to eight weeks after the first dose, and the third dose is given at least eight weeks after the second.
—Moderna: Moderna’s initial vaccine series is also approved for people 6 months and older and is given in two doses four to eight weeks apart. Both Moderna and Pfizer shots are mRNA vaccines, meaning they use lab-created coronavirus mRNA to teach cells how to make a protein that triggers an immune response.
—Novavax: Novavax is only authorized for children over the age of 12. The initial series is given in two doses three to eight weeks apart. Unlike the mRNA vaccines, Novavax is a protein subunit vaccine, meaning it contains proteins of the virus that causes COVID-19 and an adjuvant that helps the immune system respond to those proteins.
—Johnson & Johnson’s Janssen: Johnson & Johnson’s vaccine is only available for adults 18 and older who are unable to get the Moderna, Pfizer or Novavax vaccines because of medical concerns or because of limited access to the other vaccines.
COVID-19 booster doses
Both Pfizer-BioNTech and Moderna have a bivalent booster that protects against the original COVID-19 strain and the highly contagious omicron variant. Uptake of the boosters has been slow — only about 43% of Texans who received the initial vaccine series have also received a booster dose.
Pfizer’s updated booster is available for adults and children 5 and older at least two months after their second dose of the initial series or last booster. Moderna’s booster is available for children 6 and older at least two months after the second dose of the initial series.
On Dec. 8, the FDA approved the updated booster doses for children under 5, although administration of the booster depends on which initial vaccine series they received and whether they completed that series.
—Pfizer-BioNTech: The Pfizer booster dose is available to children under 5 who haven’t finished the initial three-vaccine series. Those children will receive the original formula for the first two doses of the series and the new booster formula for the third dose. Children who have already completed that series aren’t yet eligible for the booster that targets omicron.
—Moderna: Children 6 and under who completed the initial Moderna vaccine series can get the updated Moderna booster at least two months after their last shot.
Novavax also offers a booster dose, but the Centers for Disease Control and Prevention only recommends it for people 18 and older who are unable or unwilling to get an mRNA booster, have completed the initial vaccine series at least six months ago and have not gotten any other booster dose.
The future of COVID-19 vaccines
Scientists have decades of experience in formulating annual flu vaccines. They look to Earth’s southern hemisphere, which experiences its winter season in June, July and August, for clues as to which strains will probably spread in the U.S.
SARS-CoV-2, the virus that causes COVID-19, is likely moving in that same seasonal direction, Piedra said. Once the virus follows a more predictable pattern, researchers may be able to use the same methods for formulating the flu vaccine in creating yearly COVID-19 vaccines.
What’s more difficult to predict, however, is how the addition of the coronavirus is affecting other seasonal illnesses like the flu and RSV. Cases of the respiratory illnesses surged far earlier than normal this year as use of COVID-era public health protections, like masking and social distancing, waned.
Hopefully, Piedra said, the respiratory viruses will fall into place and regain their seasonality in the next few years.
“What that will look like, I can’t tell you for certain whether it will look like pre-SARS-CoV-2 seasonality or whether it may be shifted because SARS-CoV-2 is now an added virus,” he said.
COVID-19 and flu vaccines are widely available at pharmacies like CVS and Walgreens and through Dallas County immunization clinics. It’s safe to get vaccinated against both viruses at the same time.
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