Could Delta Variant Lead to Another Surge in Chicago? Here's What City's Top Doc Thinks

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As concerns surrounding the delta variant rise globally, with the new variant believed to be behind multiple surges, could it lead to another surge in Chicago?

The city's top doc says it's possible, but due to vaccinations, she doesn't believe a potential rise in cases will be like the surges seen in 2020.

"The good news is with vaccine here, you know, I'm not expecting the major surges like we saw in one or two because they remain protective against variants," Chicago Department of Public Health Commissioner Dr. Allison Arwady said.

While Arwady and other officials have predicted the delta variant will become the dominant variant in Chicago and Illinois in the coming months, "that in and of itself is not necessarily a cause for alarm," she said.

"My worry is if we see a surge it would very much [be] concentrated in unvaccinated portions of Chicago, but I don't think, unless we see a new variant, we would be set up for the kind of major surge that threatens to overwhelm the health system where we need to do the big major shutdowns," she said. "You know, the hope is that we would be able to control it and really keep pushing vaccine. I'd of course rather avoid that and just try to get folks vaccinated now, but that's where I think we're headed."

Arwady noted, however, that new variants continue to emerge and could threaten vaccine efficacy.

"The real question for me is, do we see variants emerge where the vaccine is no longer as effective and that would be when we would probably need to be talking about boosters," she said.

While studies have shown that the available vaccines work against variants, including the delta variant, all two-dose vaccines offer significantly more protection following their second dose.

Researchers in England studied how effective the two-dose AstraZeneca and Pfizer-BioNTech vaccines were against it, compared with the alpha variant that was first detected in the U.K.

The vaccines were protective for those who got both doses but were less so among those who got one dose.

Arwady reported Tuesday that a recent study showed the Pfizer vaccine was 84% effective against the variant after two doses, but only 34% effective after the first dose.

Moderna also announced Tuesday that a new study showed its vaccine also produced promising protection in a lab setting against the delta variant and others currently circulating.

“As we seek to defeat the pandemic, it is imperative that we are proactive as the virus evolves. We remain committed to studying emerging variants, generating data and sharing it as it becomes available. These new data are encouraging and reinforce our belief that the Moderna COVID-19 Vaccine should remain protective against newly detected variants,” Stéphane Bancel, chief executive officer of Moderna, said in a statement.

Currently, little data has been released showing just how effective the Johnson & Johnson is at protecting against the Delta variant, though it is believed that the single-shot vaccine does offer protection against the variant.

Dr. Scott Gottlieb, former Food and Drug Administration commissioner, reportedly said the Johnson & Johnson vaccine appears to be about 60% effective against the delta variant.

Still, Arwady said any of the three vaccines currently being used in the U.S. continue to show good results as far as protection.

"Right now there is no recommendation if you are fully vaccinated with any of those three vaccines that you would need to get another type of vaccine or that there's a need there," she said. "And really the news continues to be good where we look at this question of will we need boosters. There was just some additional studies out that have been, you know, this is one of the biggest questions and the news really keeps looking promising that the protection for the variants we have now for the vaccines that we have now is looking quite good and quite long lasting and I'm not anticipating that we will be seeing large scale booster shots anytime very soon for the broad population."

The larger concern, she said, comes for unvaccinated individuals and potentially high-risk populations.

"The biggest thing still is that the vaccine remains really very well protected against it," Arwady said. "So across all types of variants here in Chicago, since a vaccine was fully available, 98% of our deaths, 97% of our hospitalizations have been in people who were not fully vaccinated and that has been holding, even for the delta variant. So, broadly, we definitely have some concern about the delta variant, because if there are unvaccinated social networks or neighborhoods in Chicago, even a single case is more likely to spread and more likely to cause more people to get COVID and so, the most important thing of course is to get vaccinated."

So far, there has been no recommendation from the Centers for Disease Control and Prevention surrounding booster shots with the Delta variant.

“While research continues to be published about the strong efficacy of the COVID-19 vaccines, there have been no formal recommendations regarding booster shots," Dr. Sharon Welbel, director of hospital epidemiology and infection control for Cook County Health, said in a statement.

The suburban Chicago health department said it plans to follow recommendations from the CDC's Advisory Committee on Immunization Practices (ACIP) "if and when they are made."

"It is essential that everyone who is eligible to get vaccinated get their shot now, particularly as we see the delta variant take hold in the US," Welbel said. "The COVID-19 vaccine is the best way to protect your health and the health of those around you.”

But concerns surrounding spread of the variant have prompted warnings from other health officials who say masking guidelines should continue regardless of vaccination status as the variant spreads.

On Monday, the Los Angeles County Health Department said it "strongly recommends everyone, regardless of vaccination status, wear masks indoors in public places as a precautionary measure" due to the spread of the delta variant.

The World Health Organization on Friday urged fully vaccinated people to continue to wear masks, social distance and practice other COVID-19 pandemic safety measures as the delta variant spreads rapidly, CNBC reported.

"People cannot feel safe just because they had the two doses. They still need to protect themselves," Dr. Mariangela Simao, WHO assistant director-general for access to medicines and health products, said during a news briefing from the agency's Geneva headquarters.

"Vaccine alone won't stop community transmission," Simao added. "People need to continue to use masks consistently, be in ventilated spaces, hand hygiene ... the physical distance, avoid crowding. This still continues to be extremely important, even if you're vaccinated when you have a community transmission ongoing."

Arwady noted during a Facebook Live Tuesday, however, that Chicago and Illinois are continuing to follow CDC guidance.

"The WHO is making that recommendation for the whole world," she said. "The CDC, on the other hand, has made the recommendation that people who are fully vaccinated do not need to mask, whereas people who are unvaccinated should continue to mask. Of course we see in truth, there are certainly some people here in Chicago who are unvaccinated who have probably dropped their masks, even indoors. And so, right now, while our outbreak remains in very good control locally, even with the delta here, there is not a reason to adjust that guidance, and we would be sticking with the CDC guidance that says if you're fully vaccinated you don't need to be wearing a mask indoors. But... if you're fully vaccinated and you have concerns right- you have an immune system problem, you have kids who aren't vaccinated, you are worried about people in your social network who may not be vaccinated, or you just want to be extra careful - certainly individuals are continuing in some cases to continue wearing that mask and I welcome people to do that."

She said that the new masking guidance in Los Angeles County can't be ruled out for the Chicago area in the future, however.

"I don't want to rule out, you know, that this could be something that could be a recommendation again in the future," she said. "We're keeping a really close eye on our local data here, on our genomic surveillance, and if there is a need to make a change to that recommendation it's something we would do. But right now, I think we are feeling good about where we are."

The delta variant is expected to become the dominant strain for Illinois cases by the fall, Gov. J.B. Pritzker said Monday.

So far, the Illinois Department of Public Health has identified 105 cases of the variant in the state as of data reported Thursday. That's compared to 6,561 cases of the variant first reported out of the U.K. known as the alpha variant, which is likely the most prolific-strain in the state of Illinois.

Pritzker, who wore a mask to a recent public event, said he was doing so out of an "abundance of caution" as concerns surrounding the delta variant rise.

He encouraged residents to continue to "use your mask accordingly."

"I would say from my own perspective if you're going into a heavily crowded area, you don't know if somebody is not vaccinated and so you should just bring your mask with you and keep safe," he said.

NBC Chicago/Associated Press
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