Man with big umbrella shielding from virual molecules

Many find themselves wondering what to expect and how to best protect themselves in anticipation of flu season and the ongoing COVID-19 pandemic.

Richelle Guerrero-Wooley, MD, an infectious diseases expert, answers five significant questions about the coming flu season amid the ongoing COVID-19 pandemic and how we can respond to protect ourselves and others best.

Are we expecting a more severe flu season, or is coronavirus likely to remain dominant?

We still expect coronavirus to remain dominant this coming winter. It is still difficult to predict whether this year's flu season will be more severe than the 2020-2021 season. Yet lack of the flu virus’s activity since the start of the pandemic might have reduced the population’s immunity and thus could lead to an early and possibly severe flu season, according to the Centers for Disease Control and Prevention (CDC).

What can you tell us about the various COVID-19 strains?

Viruses can mutate and produce different variants, or strains, of the same virus. Some of these variants will disappear, while others persist. Certain variants can spread more quickly and cause more severe disease. There have been several variants since the start of the pandemic, but the one of greatest concern now is the Delta variant.

Currently, the Delta variant is the predominant strain spreading in the United States. It is more contagious than the previous variants, and data suggest that it causes more severe disease. Those who are unvaccinated are at the highest risk of contracting any of the COVID-19 variants.

What can I do to continue to protect myself?

The best thing you can do to protect yourself is to get vaccinated against COVID-19. Research and trials have shown the vaccines are highly protective at preventing severe disease and death from all the variants, including Delta.

Continuing to wear a mask and washing your hands is also protective for yourself and others. The vaccine is highly but not 100% effective — meaning you can still contract a COVID-19 infection once vaccinated and can still spread the virus to others.

What would you want people to know about this year’s flu vaccine?

This season, the quadrivalent flu vaccine will protect against four different strains, including two strains of Influenza A and two strains of Influenza B.

Every year, the CDC obtains information from the flu viruses circulating during the previous flu season to predict what flu viruses might be circulating in the upcoming season. This information guides which strains are included in the flu vaccine to provide the best immunity for the next flu season — though keep in mind that efficacy varies year to year.

Even though the 2020-2021 flu season had very little flu virus circulating, the CDC reports it should not impact the efficacy of the 2021-2022 flu vaccine.

Should people get the flu and coronavirus vaccines?

Yes, it is recommended to receive both vaccines. It was previously recommended to wait 14 days between different vaccinations; however, now that we know much more about the safety of the COVID-19 vaccine, it is no longer recommended to wait, and the COVID-19 vaccine can be administered with other vaccines.

One recently passed measure to consider is that immunocompromised patients are now authorized to receive the third dose of an mRNA Pfizer or Moderna vaccine at least 28 days after their second dose. This is because their immune systems might not mount a strong enough response to the initial doses. However, it is not recommended for Jansen-vaccinated immunocompromised patients to obtain a subsequent dose.

Starting this fall, a booster dose is also recommended for all other people vaccinated with the mRNA Pfizer and Moderna vaccines. This booster should occur at least eight months after the initial vaccine series. The reason for this booster dose is to maintain immunity during an increase of mild and moderate COVID-19 infection in those previously vaccinated. A booster dose is not currently recommended for the Jansen-vaccinated persons.


Loma Linda University Health offers COVID-19 vaccinations. For more coronavirus information, visit lluh.org/coronavirus.