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

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.

Whatever is the herd immunity level, it’s going to be substantially higher when you have a variant like B.1.1.7. —Michael Osterholm, PhD, MPH

The picture in the United States, he said, is vastly different from that in low- and middle-income countries, which he said are now his biggest area for concern. Ten countries—not coincidentally the wealthiest—have received about 80% of all the vaccine that’s available. And 30 countries have not seen a drop of vaccine, he said.

Spread of the variants in the 30 countries without vaccines is important on more than one level, he said. “It isn’t about just being humanitarian right now; it’s absolutely about what we’re going to do to prevent more variants from developing that will continue to threaten the security and integrity of our current vaccines,” Dr. Osterholm said.

From heart issues to mental health issues to “long COVID”—disabling symptoms six to eight weeks after initially mild cases—the effects of the virus can be devastating, he said.

Asked whether he sees the variants as an existential threat, Dr. Osterholm said, “My view of the world is limited in terms of where we’re going.” He said he’s optimistic that if the more severe variants don’t take hold, then the supply of vaccine won’t be an ongoing problem. The real problem is how many people actually get vaccinated and at what level the population will need to be vaccinated for true protection.

“If we in this country get only 65% to 70% vaccinated or protected through natural infection, we’re going to continue to see lots of transmission occur here, which will make it more difficult as a society to open back up and actually feel confident and comfortable,” he said.

But he said he puts B.1.1.7 in the “measles category” with regard to its ease of transmission and the high threshold needed for herd immunity. “Whatever is the herd immunity level, it’s going to be substantially higher when you have a variant like B.1.1.7,” he said.

Balancing Risks

Asked how to balance the risk of the virus with the risks of the response to the virus—in particular, the social isolation—Dr. Osterholm said the effects of the response could have been improved with better policy, comparing New Zealand to Minnesota, areas that have roughly the same population. New Zealand has been able to suppress the virus while keeping its economy largely open, he said. (Minnesota had about 7,000 deaths, as of the time of his talk.)

“Is their science that much better than ours? No,” he said. Instead, the difference has been in the way New Zealand was proactive in getting ahead of potential transmissions and in how the country isolated and quarantined those infected without shutting down the economy. Those quarantined were compensated for losses, inspiring willingness to comply with recommendations to limit virus transmission.

“We never really picked a point to say, ‘This is when we will or will not open up,’” he said. “Right now, everybody is opening up because it’s the only politically correct thing they can do without losing their jobs.”

We never really picked a point to say, ‘This is when we will or will not open up.’ —Michael Osterholm, PhD, MPH

Dr. Osterholm marveled at how the rates of respiratory illnesses have plummeted in ways not explained by the mitigation measures intended to fight the COVID-19 pandemic. “In countries where there has been no effort toward mitigation, they’ll tell you they’re seeing an absolute absence of viral respiratory pathogens across all ages, and particularly in kids,” he said. “Mother Nature is doing something here that we just don’t understand.”

The bottom line, he said, is that the pandemic is still here.

“I think that this virus is telling us that it’s far from done with us,” he said, “and we’ll have to see what happens over the months ahead.”

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Thomas R. Collins is a freelance medical writer based in Florida.