EEH: COVID-19 vaccines and the circulating variants

The COVID-19 pandemic first hit the community in March 2020. Without a vaccine, the only defense was avoiding other people by staying at home, wearing masks in public and keeping physically distant.

In 2021, variants with the ability to infect more people are becoming predominant. Fortunately, there is now a powerful weapon against these variants: three COVID-19 vaccines, approved by the FDA under emergency use authorization.

Society is already seeing the benefits of vaccines in those over age 65 and in residents of long-term care facilities, the first group to receive vaccines. By the end of April, over 85% of residents over age 65 in DuPage County had received at least one dose of a COVID-19 vaccine.

While Edward-Elmhurst Health has seen an uptick in COVID-19 hospitalizations in March and April 2021, none are from long-term care facilities and few are over age 65. The spring wave of hospitalization has been predominantly middle-age and younger adults, who had not yet had their turn to be vaccinated. But now no adult needs to be vulnerable because vaccines are widely available.

How did the variants come about?

Each time SARS-CoV2 (the virus that causes COVID-19) replicates, it can mutate. With the rapid pace of viral spread worldwide, the many opportunities to mutate has led to a natural selection for variants that are more fit, that can out-compete and become dominant.

Variants that have a change in these characteristics are known as “variants of concern.” Variants being investigated but not yet proven to be significant are called “variants of interest.”

What are the variants of concern and variants of interest?

The B.1.1.7 variant, recognized first in the UK in November 2020, has several mutations causing changes to the spike protein, notably the N501Y mutation, thought to allow for better attachment to the ACE-2 receptor, resulting in increased transmissibility.

B.1.1.7 has become the predominant variant in the United States, rising from less than 1% at the beginning of January 2021, to 9.5% on March 13, 44% on March 27, and to 57% by April 10.

In South Africa, the B.1.351 variant, and in South America, the P.1 variants, carry the N501Y mutation as well as the E484K. E484K mutation changes targets on the spike protein, making antibodies less able to neutralize the virus. In fact, serum from patients who recovered from COVID-19 did not neutralize the B.1.351 variant.

However, serum from those who have received Pfizer-BioNTech or Moderna vaccines did neutralize the B.1.351 variant. This is because the levels of antibodies after immunization are significantly higher than after natural infection.

The Janssen (J&J) vaccine was trialed in South Africa (where the B.1.351 variant predominates), and though it was found to have a lower efficacy compared to the U.S., it was still highly effective in preventing severe infection, with no hospitalizations or COVID-19 deaths in vaccine participants.

The Pfizer-BioNTech phase 3 clinical trial was expanded to South Africa, enrolling 800 patients. There were nine infections in the placebo group, and none in the vaccine group. Approximately six of the nine infections were due to B.1.351 variant.

The B.1.351 accounts for 0.9%, and the P.1 variant for 3.5% of infections in the United States through April 10. Other variants of concern in the U.S. at a rate of less than 5% include B.1.429 and B.1427.

Variants of interest are B.1.526, B.1526.1, B.1.525, and P.2.

In India, with less than 10% of the population having received a first-dose of a vaccine and less than 3% not fully immunized, there is fertile ground for widespread transmission of viral variants, leading to the largest daily cases and death toll in the history of COVID-19. The B.1.1.7 variant has become dominant in the province of Punjab. While a new variant, B.1617, the so-called “double mutant” is a variant of interest, of unknown significance, circulating in other parts of India.

While the efficacy of the three COVID-19 vaccines has been proven across adults of all age groups and medical conditions, there is not enough information to know the level of protection in those who have a medically compromised immune system.

Are the COVID-19 vaccines more widely available now?

Vaccines are now widely available for everyone age 12 and older. The faster more people can become fully immunized, the less variants will continue to spread through our community.

Becoming fully immunized means that someone is not only protected from getting severe illness with COVID-19, they’re also less likely to become infected and transmit the virus to someone else.

For more information, visit www.eehealth.org/coronavirus.