What is the Delta variant?

Delta is the name for the B.1.617.2. variant of COVID-19, which originally surfaced in India in December 2020. This strain spread rapidly, becoming the dominant strain of the virus in both India and then Great Britain. Now, it has reached the United States, and the Delta variant is the most dominant form of COVID-19, accounting for more than 83% of new cases.

Why is the Delta variant a concern?

The Delta variant is a strain of COVID-19 that has mutations in the spike protein that make it easier for it to infect human cells. That means people may be more contagious if they contract the virus, and it is easier to spread it to others.

Putting the Delta variant’s infection in perspective, the Delta (India) variant is about 50% more contagious than the Alpha variant. The Alpha (United Kingdom) variant was already 50% more contagious than the original coronavirus first identified in China in 2019. Reports from the United Kingdom do highlight that the Delta variant is more severe and deadly, particularly among unvaccinated individuals.

The Delta variant presents the greatest risk to unvaccinated individuals, but also poses a risk to vaccinated individuals as vaccines are less effective against it. Pfizer and Johnson & Johnson have identified that their vaccines’ effectiveness against contacting COVID-19 decreases against the Delta variant, but are still very effective against severe symptoms and hospitalizations. Unfortunately, since their effectiveness has dropped, breakthrough cases are being reported.

Breakthrough cases are defined as an individual who is fully vaccinated, but still contracts COVID-19. Currently, the Centers for Disease Control and Prevention (CDC) is only monitoring breakthrough cases in those who are hospitalized or have severe symptoms. This results in under reporting, so it is unknown how many breakthrough cases have mild symptoms.

Why are we seeing the Delta variant and why is it worse than other variants?

The Delta variant originated because we did not have protection against COVID-19. When a virus widely circulates in a population, it is constantly replicating, and this increases the opportunity to undergo changes or mutations. Typically, most viral mutations have little-to-no impact on the virus’s ability to cause infections and disease, but depending on where the changes are in the virus’s genetic material, they may affect a virus’ properties, such as transmission (spreads quickly or slowly) or severity (cause more or less severe disease).

The mutation in the Delta variant has made it so it can spread much easier and is resulting in more severe symptoms. The Delta variant is thought to spread 2-3 times more quickly than previous variants, which means it can infect more people more quickly, which is why there are rapid spikes in cases.

How to protect yourself against the Delta variant?

The best way to protect yourself is to get vaccinated. Variants form because they spread from person to person and mutate as they replicate; if we can stop the spread, we will slow down or stop variants from forming.

If you are unable to be vaccinated due to religious or medical reasons, wearing a facemask, social distancing and practicing good hand hygiene will minimize the spread of COVID-19 as well.