SARS-CoV-2 Variants: Pandemic Expert Pushes Need for Continued Caution

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Michael Osterholm, PhD, MPH, director of the Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota in Minneapolis, has a cautionary tale for any-one feeling supremely confident that we have “everything going in our favor” regarding the COVID-19 pandemic.

In the spring of 2020, the city of Manaus in northwestern Brazil had a “house on fire” outbreak, with 75% of the residents infected between mid-May and early July, and “astronomical” levels of death. Bodies were heaped into mass graves. Afterward, academic papers were written declaring that the city had, in all likelihood, reached herd immunity, the level at which the virus is unable to take hold and thrive.

But in early to mid-November, the nightmare started all over again, with a worse outbreak through early January than they’d had previously, with even more deaths. Many of those cases were associated with people who had previously been infected and recovered. This time, the city was stricken with the P1 variant, a mutation on the binding site of the spike protein of the virus. COVID-19 had found a second life in Manaus.

During the American Society of Pediatric Otolaryngology’s Kerschner Lecture at the virtual Combined Otolaryngology Spring Meetings (COSM) in April, Dr. Osterholm, as part of the American Society of Pediatric Otolaryngology program, delivered a sobering talk underscoring the uncertainty and potentially dire effects that new SARS-CoV-2 variants could have, even as vaccines ramp up in the world’s wealthiest nations and society is allowing itself to feel hope that the pandemic is nearing an end. “We are now living in the age of the variants,” he said. “This is one of the curveballs that we didn’t understand with the coronavirus pandemic, unlike influenza.”

Variant Concerns

The most dominant common “variant of concern” in the United States, B.1.1.7, is more transmissible than the original SARS-CoV-2—50% to 100% more, Dr. Osterholm said. And data suggest that it’s 50% more likely to cause severe illness. With the spread of this strain, there has been a “remarkable” rise in the number of severe illnesses in people aged 20 to 49, he said.

There also seems to be greater transmission at school-based and sporting activities among children that had not been seen until B.1.1.7 came onto the scene, he said. While he had been supportive of children going back to in-person schooling when transmission seemed to be low among schoolchildren, he now views it differently. “B.1.1.7 turns out to lay that on its head,” Dr. Osterholm said.

The P1 variant that struck Manaus reduces the level of protection from vaccines and from natural infection by the original virus. It also causes more severe illness. The B.1.351, or South African variant, is similarly associated with a reduction in vaccine protection, but isn’t associated with the same frequency of severe illness as the P1, Dr. Osterholm said.