Auburn professor discusses Delta variants of COVID-19, outlines what people may expect in coming months
Viruses are known to constantly mutate and change, and the COVID-19 coronavirus is no exception. The Delta and Delta Plus variants of the virus have drawn considerable attention lately after becoming more predominant in the United States.
Both variants were first detected in India. The Delta variant is now found in more than 80 countries throughout the world. It accounts for approximately 20% of infections in the United States, with health experts predicting it could become the country’s most dominant type.
India has dubbed Delta Plus a “variant of concern,” and there are fears it could potentially be more transmissible than the original strain. Delta Plus is reportedly in at least 11 countries so far.
Marilyn Bulloch, an associate clinical professor in Auburn University’s Harrison School of Pharmacy and an infectious disease expert, discusses the Delta variants and outlines what we can expect in the coming months.
What is the Delta variant of COVID-19?
The Delta variant is more officially known as COVID B.1.617.2. All viruses mutate—it is constant and expected. When they develop mutations, it differentiates them from other variants of the virus out circulating among people. The Delta variant is just one of many known mutated strains of the SARS-CoV-2 virus.
However, we look at the types of mutations that occur to determine if it is going to be clinically worrisome. There are certain genetic markers that may impact how contagious it is, how severe of disease it may cause and how susceptible it is to available treatments. The CDC has labeled this a “variant of concern” because there is evidence that it is spread more easily, can cause more severe disease, including hospitalizations and death, and is associated with reduced effectiveness of available treatments and vaccines.
How is it different from what has been circulating since the pandemic began?
This is still coronavirus, and it is still the SARS-CoV-2 virus. It has just mutated, much in the way other viruses mutate. The flu is a great example of where this also occurs. Some years, flu season is light, while other years, the circulating strain is really harsh on the body. It all depends on the circulating strains and the way it has evolved.
It is not surprising that the same variability would exist with SARS-CoV-2. It appears that the COVID-19 Delta variant may have different symptoms than what we have come to associate with COVID-19. Researchers with the COVID Symptom Study have reported that the most common symptom in those infected with the Delta variant is headache, along with a runny nose, sore throat and a fever, much like a bad cold. There appears to be less cough or loss of smell.
As more people are infected, we will continue to learn more about it. However, the “bad cold” with this variant seems more likely to progress to more severe disease and at a faster pace than what we say with infections from other variants.
It is also less discriminating by age. When COVID-19 first emerged, younger patients, including children, were less susceptible to infection and severe infection. Whatever initial natural protection that may have existed in this age group in 2020 seems to decline more and more with each variant that emerges.
The concerning thing with this is we are learning that almost half of all children who develop COVID-19 symptoms experience Long COVID-19, and we still do not know the full implications of the virus over the life span. We do know that there are many other viruses that are spread through the respiratory route that did cause devastating long-term effects, but thankfully we do not see that today because many of those viruses have vaccines.
What makes the Delta variant more concerning?
This variant seems to be more contagious, and patients can become very sick pretty quickly. Based on recently released research, including a study in “Lancet” in June, patients infected with the Delta variant are twice as likely to be hospitalized, particularly those with five or more co-morbidities. However, the increased risk of hospitalization appears to be broad reaching across age groups, gender and previous health status.
One other concern is the ability we may have to treat the variant. We have made great strides in developing neutralizing monoclonal antibodies, which overall have been extremely helpful in preventing the progression of mild COVID-19 to severe disease in high-risk patients. Unfortunately, this variant has a particular substitution in the virus’ spike protein that may make the monoclonal antibodies less effective. It is similar to the way bacteria develop resistance to antibiotics.
It sounds like this virus has mutated yet again and there is now a Delta Plus variant. Will we continue to see it mutate and mutate, causing more concern for the unvaccinated?
We will continue to see the virus mutate and change. It is how viruses survive. We have thousands of strains of influenza now and similar amounts with other viruses. There is no way to predict how strong each strain will be. With other viruses, some are more virulent than others.
How can we stop or slow the spread of the Delta variants?
The best thing people can do is to get vaccinated if they are able to. It seems that protection against this strain may not be seen for up to 28 days after getting immunized. The Delta variant is anticipated to become the dominant strain by fall and that is the same time that we enter cold and flu season. It is really important to give your body enough time to mount an immune response. It is also important to continue common-sense infection prevention practices—things like good hand washing or staying away from others if you feel sick. These are things that we recommended long before COVID-19 because we know it reduces transmission of pathogens.
The vaccines available are reportedly effective, so is vaccination vital?
Vaccination is absolutely key. While there is not a vaccine for anything that is 100% effective, we know that the Moderna and Pfizer/BioNTech vaccines have about an 79-88% protection rate. Based on what we know of vaccines in general against viruses, even if someone who is vaccinated becomes infected, their symptoms and clinical course are more likely to be mild rather than severe. We are seeing that in the community. The mRNA vaccine is 96% effective at preventing hospitalizations in those who do get infected.
Is vaccine availability an issue in Alabama?
When the vaccines first came out, there was a huge interest in it, but it was extremely difficult to get an appointment. There were support groups on social media dedicated to helping people locate an available immunization slot. Since then, the number of providers who have vaccine available has dramatically increased. A lot of this is due to increased distribution and involvement of pharmacies across the state.
Unfortunately, there are still some rural and/or underserved areas that may have limited access. Even if there is a location to be vaccinated, the hours may not be compatible with the hours someone may be able to get there due to work or other responsibilities. I think there are some people who have chosen not to get vaccinated because they feel they have natural immunity after having been infected with COVID-19 in the last year and a half. Unfortunately, their immune systems have not been exposed to this particular strain, and it is entirely possible, if not probable, that their body would be susceptible to infection with the more potent variant.
In Alabama, we were becoming encouraged by the downward trend in COVID-19 diagnoses, hospitalizations and deaths. Over the past few weeks, there has been a small, but noticeable upward trend in cases and deaths. This underscores that we have a lot of people in our state who are still vulnerable.
Why are people hesitant about getting vaccinated?
In a poll conducted in the spring, there was reluctance among all groups, not just minorities, regarding the vaccine. About 49% of people who responded said they were somewhat or very unwilling to get the vaccine. People, particularly minorities, reported that they want the choice to get the vaccine rather than to feel like they are being targeted or forced to do so. There are some concerns in the Hispanic/Latino communities about deportation and cost.
However, the biggest reason is that they don’t think it has been studied enough, and they will get the vaccine when they feel it is safe. With the number of people who have been vaccinated in the U.S. and worldwide, I think it is really important that we start getting data from our vaccination efforts and providing that information to the public. With the real-world use, we should have much more data than a drug or vaccine usually has before it gets FDA approved to show to the public the efficacy and safety of these vaccines.
I think it is also important to provide people perspective about how long drugs and vaccines are traditionally studied before they are approved for use in the U.S. These surveys rarely if ever ask people how long the vaccine would have to be studied before they felt comfortable taking it, but I think most people would be surprised at the duration of most clinical trials—they often do not last as long as most people would think. Unfortunately, we don’t do a great job of explaining the process very well to those outside of health care.
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