MU researchers identify mutations of Delta, Delta Plus variants

Findings help explain COVID-19 reinfections, Delta variant infections despite vaccination efforts.

November 12, 2021


Brian Consiglio: As the COVID-19 pandemic has continued to evolve around the world, two emerging variants, known as Delta and Delta Plus, have led to infections even among vaccinated individuals and those who have previously tested positive.

A recent study at the University Missouri, led by Kamlendra Singh, a professor in the MU College of Veterinary Medicine, MU undergraduate student Austin Spratt, and others sought to discover why the emerging variants have been so infectious.

Singh: “The main question we were trying to answer is why are people, even though they have been given the vaccine or already been infected with covid,  why are they still getting infected with these new variants. We thought that perhaps the answer was in the structure of the virus and how that is changing over time.”

Consiglio: The research team analyzed protein sequences for more than 300,000 COVID-19 samples of Delta and Delta Plus variants. They identified specific mutations that are far more prevalent in Delta Plus infections compared to Delta infections, providing important clues about the structural changes to the virus and its ability to infect even those with antibodies either from vaccination  or previous infection.

Singh: “Viruses are changing all the time. The reason they can still get infected is because the mutations of these new variants are located in a place where the spike protein and the antibodies meet, and so if that place is changed, the body interprets it as a new virus, and so the vaccine doesn’t know how to handle it.”

Consiglio: The findings highlight the need to expand the toolbox in the fight against COVID-19. While vaccines have been effective, the development of antiviral drugs will likely also play an important role in responding to the pandemic moving forward.

For more on this research, visit

I’m Brian Consiglio, with a Spotlight on Mizzou.

Learn more about the research here

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