How Will the New COVID-19 Variants Affect Our Vaccine Strategy? by Angela Dunn, MD, MPH

 

Just as we are seemingly near the end of the COVID-19 pandemic, we start identifying mutations in the virus that causes COVID-19 (SARS-CoV-2). These mutations are causing concern because they are producing variants that are spread more easily, cause more severe disease, or are less susceptible to vaccines or treatment. However, this was not unexpected. Scientists started preparing for mutations and adjusting the COVID-19 vaccines before any variants were identified.

Let’s take a closer look at the COVID-19 variants, whether the current vaccines work against them, and whether we’ll need to continue to develop vaccines to keep up with ongoing mutations.

Why is the coronavirus mutating?

Mutating viruses may sound like something out of a sci-fi movie. But it’s actually very common for a virus to mutate. 

Here’s how it works: Once a virus has infected a person, it starts replicating — making more and more copies of itself. Errors can happen in this replication process. It’s similar to making chocolate chip cookies. The last time you made a batch, was every single cookie exactly the same? Likely not. They were probably different sizes and shapes.

Replication errors in viruses are called mutations. The virus with the mutation is similar to the original virus, but not an exact copy. It is called a variant. Often, the original virus and the variant act the same. Much like the size or shape of a chocolate chip cookie doesn’t change how it tastes.

Rarely, mutations are significant and cause a variant to act differently. If you were to double the baking time of your chocolate chip cookies, they would burn and certainly taste different. Some mutations change how easily the virus spreads, the severity of disease it causes, or how well a vaccine or treatment works against it.

The virus that causes COVID-19 has mutated over 7,000 times since the beginning of the pandemic. The recently identified variants spread easier and are more likely to cause severe disease. COVID-19 vaccines and treatments may not work as well against some variants. Public health scientists and vaccine manufacturers are working to improve our current COVID-19 vaccine strategy. This will help protect us against the new COVID-19 variants.

How are COVID-19 variants detected?

Much like a human, a virus has a genome — its own unique DNA that acts like a manual for everything that virus is and does. Scientists can map a virus’s genome by a process called whole genome sequencing. This allows them to identify how the virus is changing over time and creating new variants. 

The CDC is working with public health partners to identify the variants currently spreading. The CDC, state and local health departments, commercial laboratories, and universities are performing whole genome sequencing on laboratory samples that are positive for COVID-19. This allows scientists to identify new variants or those already identified in other countries.

How many COVID-19 variants are there?

Multiple COVID-19 variants have been spreading globally. However, only five variants thus far are considered variants of concern. Variants of concern have evidence of being easier to spread, harder to vaccinate against or treat, or more difficult to detect with current COVID-19 tests. The CDC updates the list of variants of concern as information about new variants becomes available.

The CDC and its public health partners put extra effort into identifying variants of concern and investigating people who are infected with them. These efforts help track where the variants are spreading and inform public health recommendations.

1) The five variants of concern and their characteristics aB.1.1.7 (first identified in the United Kingdom)

• 50% more easily spread
• Increased severity — more hospitalizations and deaths
• Minimal impact on vaccines and treatments

2) P.1 (first identified in Brazil)

• Reduced effectiveness of vaccines and treatments

3) B.1.351 (first identified in South Africa)

• 50% more easily spread
• Reduced effectiveness of vaccines and treatments

4) B.1.427 (first identified in California)

• 20% more easily spread
• Significantly reduced effectiveness of some treatments
• Reduced effectiveness of vaccines

5) B.1.429 (first identified in California)

• 20% more easily spread
• Significantly reduced effectiveness of some treatments
• Reduced effectiveness of vaccines

B.1.1.7 is the most widely circulating variant in the United States. All 50 states have identified at least one person infected with it. While the vaccines work well against B.1.1.7 (more on this in the next section), it is still important to keep track of the other variants that aren’t as susceptible to the current COVID-19 vaccines. These variants may require a new vaccine or booster dose.

How well do the current COVID-19 vaccines work against the new coronavirus variants?

The vaccines don’t appear to work as well against some variants. However, the current FDA-approved COVID-19 vaccines are very effective at preventing hospitalization and death due to COVID-19. Two of the most concerning COVID-19 variants spreading were first identified in the UK (B.1.1.7) and in South Africa (B.1.351). Both variants have the same key mutation and are more easily spread. 

Moderna and Pfizer conducted laboratory studies to see if their vaccines were still effective against these new strains. The Moderna study showed no impact of the UK strain on its vaccine. There was reduced but still significant efficacy against the South African strain.

Pfizer conducted two studies. The first study showed its vaccine had efficacy against the key mutation found in both strains. The second study showed efficacy against all of the mutations found in the UK strain.The single-dose Johnson & Johnson vaccine was studied in South Africa where 95% of the infections in the study were caused by the B.1.351 variant. The vaccine was found to have 57% efficacy at preventing all COVID-19 disease, and 82% efficacy at preventing severe disease (disease causing hospitalization and death).

Are new vaccines being developed for the variants?

Vaccine manufacturers, such as Moderna and Pfizer, have been preparing for possible COVID-19 mutations before any new variants were identified. Even though we know the current vaccines offer protection against the new variants, manufacturers will continue to monitor the effectiveness of their vaccines. 

There is currently no indication that the vaccines need to change. However, vaccine manufacturers are testing new booster shots to improve protection against the identified variants and potential future mutations.

The updated booster shots will need to go through the same rigorous evaluation as the first shots — which means the companies will be studying the updated shots to make sure they are safe and effective. So it will likely be several months before any updated booster shot is available.

In the meantime, you don’t need to wait until a new vaccine or booster shot is available to get vaccinated. The FDA-approved COVID-19 vaccines offer great protection against disease, including the variants. It is important that you get the COVID-19 vaccine when it becomes available to you. This is a key step in ending the pandemic.

How soon until the COVID-19 variants overtake vaccination efforts?

COVID-19 variants are spreading in the United States. However, our daily COVID-19 infections continue to decrease. The same public health guidelines that have protected us throughout this pandemic still work for variants — wear a face-covering, practice physical distancing, wash your hands, and stay home if you are sick. Following these guidelines, and getting vaccinated when it is your turn, will help prevent a surge due to variants.

The CDC and public health departments are monitoring the spread of variants. In addition, they are identifying anyone who gets infected with COVID-19 after being vaccinated. Thankfully, these cases are very rare. This is an indication that the vaccines are working, even as variants are spreading.

Is a universal coronavirus vaccine possible?

With all of this talk about the COVID-19 virus mutating, it is hard to imagine that we will never need another COVID-19 vaccine again. However, it is possible. 

There are several vaccines that provide long-term immunity. The measles vaccine, for example, likely provides lifetime immunity against the virus. Typically individuals get their final measles vaccine shot between ages 4 and 6 years, and never need another measles vaccination again. On the other hand, we need to get a flu vaccination every single year. This is because the flu virus mutates so much that the vaccine needs to be updated in order to protect against illness.

It is still unclear whether or not we will need an annual COVID-19 vaccination, a booster shot, or nothing after our first COVID-19 vaccination series. Though rare, there are reports of people having a very mild form of COVID-19 after being vaccinated. Scientists are exploring what this means — for instance, how long immunity lasts after a vaccine — and finding ways to make vaccines more effective and long-lasting.

The bottom line

Some COVID-19 variants spread more easily, cause more severe illness, or are not affected as much by vaccine or treatment. However, the FDA-approved COVID-19 vaccines provide effective protection against all known spreading COVID-19 variants. To help prevent the spread of COVID-19 variants and another surge, get a vaccine as soon as you are eligible. You may need an additional vaccine or booster shot in the future, but it is too early to tell at this point.

Angela Dunn, MD, MPH, is a public health physician who seeks to ensure all individuals have good information at their fingertips to make the best health decisions.

Read more:

• What to Look Out for When Monitoring COVID-19 Vaccine Side Effects
• Did the COVID-19 Vaccine Work if I Didn’t Feel Any Side Effects?