Is the Delta variant a game changer?

By Amichai Perlman, PhD, PharmD
Medically reviewed
July 16, 2021

In the past few months, many have sighed in relief as a whopping 185 million fellow Americans have gotten at least one dose of a COVID-19 vaccine, and we’ve been able to regain some type of normalcy. 

Vaccine uptake across the U.S. has been accompanied by a dramatic decrease in the number of COVID cases, hospitalizations and deaths.

However, in recent weeks the concerns around the Delta variant of the coronavirus has grown. Rates of COVID have begun increasing in some areas, and there is talk of a third dose of vaccine—is this a significant game changer?

So what is a coronavirus variant?

A coronavirus variant is a genetically altered version of the virus. Variants have small changes in the genes encoding the structure of their proteins, which in some cases make them more contagious and cause of concern. This means they can spread more easily, cause more severe disease, or compromise the efficacy of available vaccinations, tests, or treatments.  

Variants will continue to emerge as long as the virus continues to have people to infect. This is because the virus wants to survive, and will change to try and stay alive longer. The more “hosts” (or people to infect) there are, the longer the virus can survive, and potentially mutate to create a new variant.

The first variant of concern of the coronavirus was the UK variant, now referred to as the Alpha variant. The variant currently drawing attention is Delta—formerly known as the variant from India.  

What do we know about the Delta variant?

Evidence from around the world has shown that the Delta variant is much more contagious than earlier variants. It’s been estimated to be between 40% and 80% more transmissible than the Alpha variant, and currently the most dominant variant in many places around the world. 

Available data shows being vaccinated significantly reduces the risk of being infected by the Delta variant. However, vaccinated people still can, and do, become infected. In some cases, symptoms may be severe.

But this does not mean that we’re back in square one. 

Data from Canada, England, Scotland, Israel, and Singapore shows that vaccinated people have over a 90% reduction in the risk of COVID-19-related hospitalization. Other data estimates that the reduced risk of infection for fully vaccinated individuals with the mRNA vaccines range between 64-88% efficacy. 

The possibility of a booster shot

It is possible that over the next weeks or months a third vaccine “booster” dose will be necessary and helpful. This is common for many vaccines!

But now, there’s one thing we know for sure: the more people that are vaccinated, and make smart choices to minimize unnecessary risky exposures, the less of a chance the coronavirus will have to continue spreading and mutating. 

We’re not back to square one, but there are ways to be smart about the coronavirus Delta variant.

K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.

Amichai Perlman, PhD, PharmD

Dr. Perlman is a clinical pharmacist and pharmacoepidemiologist, with over 10 years of experience advising patients and clinicians on medication use, personalization, and safety. He has extensively published peer-reviewed research addressing medication safety.