Auburn infectious disease expert remains concerned about COVID-19 mutations and low vaccine rates

Published: September 10, 2021
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As we continue to navigate the COVID-19 pandemic, vaccines and vaccination status dominate the conversation. With variants of the virus continuing to emerge and breakthrough cases becoming common, many have questions regarding the vaccines and what it would take to end the pandemic.

Spencer Durham, an infectious disease expert within Auburn University’s Harrison School of Pharmacy, attempts to answer some of these questions. An associate clinical professor in the Department of Pharmacy Practice, he is a board-certified pharmacotherapy specialist and a board-certified infectious diseases pharmacist. His areas of scholarly interest include antimicrobial stewardship, the treatment of multidrug-resistant organisms and the safety and efficacy of vancomycin. Durham is also a member of Alabama’s Coronavirus Task Force.

Media interested in interviewing Durham can contact Communications Director Preston Sparks at 334-844-9999 or preston.sparks@auburn.edu.

Why is the delta variant more concerning than the original strains of COVID-19?

The delta variant is a mutation of the original strain of COVID-19. All viruses are expected to mutate, and the more opportunity the virus has to replicate, the more mutations will occur.  The original strains of COVID have mutated many times now into different variants that have caused outbreaks in different parts of the world. The delta variant first originated in India but has now become the dominate strain the United States. It is one of the most worrisome variants though because it is much more contagious than other strains of COVID. The “viral load,” which is a measure of how much virus is in a person’s system, is about 1,000 times higher with delta than the original strains of COVID. The higher the viral load, the more easily the virus will spread to other people. 

Why are some people who are already vaccinated getting sick with the delta variant, otherwise known as experiencing a breakthrough infection?

In addition to being more contagious, the delta variant has figured out how to evade some of the antibodies produced by the vaccines. Essentially, this means that some people may experience COVID symptoms even if they have been vaccinated. However, the vast majority of cases of the delta variant is occurring in people who have not received the vaccine at all.

If people can still get sick from the delta variant even if they have been vaccinated, should people still get vaccinated?

Absolutely! It is important to note that, while vaccinated people may still get symptoms if they acquire the delta variant, the symptoms are almost always considered mild. The vaccines are still very effective against the delta variant in terms of keeping people out of the hospital and keeping them from getting severely ill, or even moderately ill, from COVID. So, vaccination is still incredibly important in protecting people from the serious complications from the delta variant. 

Vaccination rates in Alabama are still very low. If vaccination rates were to increase, would that help fight the delta variant?

Yes, it absolutely would. The more people we get vaccinated, the less likely the delta variant is to spread in the community. There will still be some spread of the disease, but it will be much less than it currently is. So, vaccination helps protect people who cannot get the vaccine (i.e., young children) from acquiring COVID.

Additionally, increasing vaccine rates will help prevent an even more dangerous variant from emerging. I mentioned earlier that viruses mutate when they replicate. Vaccines help prevent COVID from replicating and will therefore help to prevent new and more dangerous strains from developing.

There has been a lot of talk about the COVID vaccines affecting female fertility. Can you comment on this?

There is no scientific reason to expect that the COVID-19 vaccines would affect fertility. This myth has been perpetuated through a false post on social media that said the COVID spike protein, which is targeted by the vaccines, is very similar to another protein called synctin-1, which is involved in the growth and attachment of the placenta during pregnancy; the false idea was that the COVID vaccines might therefore “attack” this other protein and cause infertility. 

However, in reality, the COVID spike protein is very different from synctin-1. In the clinical trials that brought the COVID vaccines to the market in the United States, there has been no loss of fertility in women who participated. In fact, several women who received the COVID vaccine became pregnant afterwards. So, the bottom line is that there is no reason to suspect the vaccines would have any effect on fertility. 

The CDC recently recommended that people who are immunocompromised receive a third dose of the Pfizer or Moderna vaccines. What can you tell us about this?

People who are immunocompromised do not always develop a good immune response to the first two doses of the vaccines, which means they may not be as protected against COVID infection. This is important because these same people are at a higher risk for complications if they get COVID.

However, studies have shown that a third dose of the vaccine greatly increases protection. Because of this, the CDC and FDA recommend people with moderate or severe immunocompromising conditions get a third dose of the vaccine at least four weeks after the second dose. Here are some examples of individuals who can get a third dose now:

  • People receiving treatment for cancer
  • Those who have had an organ transplant or stem cell transplant
  • People taking medications to suppress the immune system, including people taking high doses of corticosteroids
  • Moderate or severe primary immunodeficiency (DiGeorge syndrome, Wiskott-Aldrich syndrome)
  • Advanced or untreated HIV infection

There has been a lot of talk recently about everyone, not just immunocompromised people, needing a third dose of the Pfizer or Moderna vaccines. What can you tell us about this?

We know that antibodies made by the COVID vaccines slowly decrease over time, meaning that the body may not be able to fight off COVID once these antibodies get too low. Because of this, many different experts have recommended a third vaccine dose, and the FDA and the Advisory Committee on Immunization Practices is currently evaluating if they will make this recommendation. 

It is very likely they will recommend that everyone should receive a third dose approximately eight months after they received their second dose. These third doses will likely begin shortly after approval by the FDA and ACIP. It is important to remember that immunocompromised people should go ahead and get their third dose now.

What about people who received the one-shot Johnson & Johnson vaccine? Should they get a second dose?

It is likely that people who received the J&J vaccine will need a booster dose at some point.  However, because this vaccine was not available until a few months after the Pfizer and Moderna vaccines, there is not yet as much data on how long the antibodies last for this vaccine. This is currently being evaluated. For now, no one who has received the J&J vaccine needs a second dose, but this may change over time. 

More Information To arrange an interview with our experts, please contact Preston Sparks, director of university communications services, at preston.sparks@auburn.edu.