As Delta variant turns into dominant strain in California, scientists detect 'Delta plus'

Some scientists studying this mutation are concerned a booster shot of the COVID-19 vaccine might be needed.

ByLuz Pena KGO logo

Tuesday, July 6, 2021

We know about Delta strain, but 'Delta plus?' Scientists explain

The Delta variant continues to spread across the U.S. and now scientists are reporting a new version of this variant, the Delta plus.

SAN FRANCISCO (KGO) -- The Delta variant continues to spread across the U.S. and now scientists are reporting a new version of this variant, the Delta plus.

ABC7 News reporter Luz Pena is part of our vaccine team and spoke to infectious disease experts who are studying this mutation and are concerned a booster shot of the vaccine might be needed.

Accounting for nearly 36% of COVID-19 cases sequenced in June across California is the Delta variant. Now, scientists detected a new mutation of the Delta variant, the Delta plus.

Working to stay ahead of these mutations and studying the Delta variant is UCSF's Dr. Nevan Krogan and his team at the Quantitative Biosciences Institute at the University of California San Francisco.

Luz Pena: "What is difference between the Delta and the Delta plus?"

Nevan Krogan, PhD: "The Delta variant has 18 different mutations and 7 of them are in the spike protein. The Delta plus variant has an additional mutation in spike, where some people are saying is resulting in increased transmissibility."

Last week Dr. Krogan met with nearly 50 scientists in New York City to understand how the Delta variant is mutating and morphing into new strains like the Delta plus.

VIDEO: 'CA could backtrack' amid rapid spread of COVID-19 Delta variant, doctors say

Bay Area health officials are concerned about the rapid spread of the Delta variant, warning outbreaks could trigger a setback for the state.

"It's mutating compared to other viruses incredibly quickly. I think a big part of that is because there is a significant percentage of people who are getting infected and are asymptomatic," said Dr. Krogan and added, "So the world is really a huge petri dish."

Infectious Disease Specialist Dr. Monica Gandhi says the Delta plus is a vital example of the need for a global vaccination plan. The Delta variant was first detected in India then mutated into the Delta Plus and now it's in the US.

"The Delta plus variant has been detected in Utah," said Dr. Gandhi.

But even with a new mutation, the vaccines continue to prove effective against these variants.

"It's true that it's mutating, but the one thing to remember about the immune system is that when we get protection from the vaccines, you form T-cells across 85 parts of the spike protein. Losing 11 to 13 places on the spike protein, you still have very strong T-cell immunity from the vaccine," said Dr. Gandhi.

Luz Pena: "Is there a chance that there will be a need for a booster shot because of the Delta and the Delta plus variants?"

Dr. Monica Gandhi: "There is a chance of that, like older people. I think it's going to be a decision that the United States makes, likely to emulate the U.K. and Israel whether older people and immunosuppressed patients need a third shot"

Dr. Krogan says more data needs to be collected to confirm if this Delta plus is more transmissible than the Delta variant.

Luz Pena: "Can this variant continue to morph into the Delta plus plus?"

Nevan Krogan, PhD: "Yes, all these viruses, if given the chance can and will mutate and the majority of these mutations will have no effect on the virus, but some will actually help the virus infect others and replicate better.

According to experts, the Delta variant is the dominant variant in California and the more unvaccinated people there are, the more places these variants have to continue mutating.

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