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Suppression of COVID-19 waves reflects time-dependent social activity, not herd immunity

Scientists developed a model showing that a fragile, temporary state of immunity emerged during the early epidemic but got destroyed as people changed their social behaviors over time, leading to future waves of infection Credit: Brookhaven National Labor

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Scientists developed a model showing that a fragile, temporary state of immunity emerged during the early epidemic but got destroyed as people changed their social behaviors over time, leading to future waves of infection

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Credit: Brookhaven National Laboratory

UPTON, NY–Scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and the University of Illinois Urbana-Champaign (UIUC) have developed a new mathematical model for predicting how COVID-19 spreads. This model not only accounts for individuals’ varying biological susceptibility to infection but also their levels of social activity, which naturally change over time. Using their model, the team showed that a temporary state of collective immunity–what they coined “transient collective immunity”–emerged during early, fast-paced stages of the epidemic. However, subsequent “waves,” or surges in the number of cases, continued to appear because of changing social behaviors. Their results are published in the Proceedings of the National Academy of Sciences.

The COVID-19 epidemic reached the United States in early 2020, rapidly spreading across several states by March. To mitigate disease spread, states issued stay-at-home orders, closed schools and businesses, and put in place mask mandates. In major cities like New York City (NYC) and Chicago, the first wave ended in June. In the winter, a second wave broke out in both cities. Understanding why initial waves end and subsequent waves begin is key to being able to predict future epidemic dynamics.

Here’s where modeling can help. But classical epidemiological models were developed almost 100 years ago. While these models are mathematically robust, they don’t perfectly capture reality. One of their flaws is failing to account for the structure of person-to-person contact networks, which serve as channels for the spread of infectious diseases.

“Classical epidemiological models tend to ignore the fact that a population is heterogenous, or different, on multiple levels, including physiologically and socially,” said Alexei Tkachenko, a physicist in the Theory and Computation Group at the Center for Functional Nanomaterials (CFN), a DOE Office of Science User Facility at Brookhaven Lab. “We don’t all have the same susceptibility to infection because of factors such as age, preexisting health conditions, and genetics. Similarly, we don’t have the same level of activity in our social lives. We differ in the number of close contacts we have and in how often we interact with them throughout different seasons. Population heterogeneity–these individual differences in biological and social susceptibility–is particularly important because it lowers the herd immunity threshold.”

Herd immunity is the percentage of the population who must achieve immunity in order for an epidemic to end.

“Herd immunity is a controversial topic,” said Sergei Maslov, a CFN user and professor and Bliss Faculty Scholar at UIUC, with faculty appointments in the Departments of Physics and Bioengineering and at the Carl R. Woese Institute for Genomic Biology. “Since early on in the COVID-19 pandemic, there have been suggestions of reaching herd immunity quickly, thereby ending local transmission of the virus. However, our study shows that apparent collective immunity reached in this way would not last.”

“What was missing prior to this work was that people’s social activity waxes and wanes, especially due to lockdowns or other mitigations,” added Nigel Goldenfeld, Swanlund Professor of Physics and director of the NASA Astrobiology Institute for Universal Biology at UIUC. “So, a wave of the epidemic can seem to die away due to mitigation measures when the susceptible or more social groups collectively have been infected–what we call transient collective immunity. But once these measures are relaxed and people’s social networks are renewed, another wave can start, as we’ve seen with states and countries opening up too soon, thinking the worst was behind them.”

Ahmed Elbanna, a Donald Biggar Willett Faculty Fellow and professor of civil and environmental engineering at UIUC, noted transient collective immunity has profound implications for public policy.

“Mitigation measures, such as mask wearing and avoiding large gatherings, should continue until the true herd immunity threshold is achieved through vaccination,” said Elbanna. “We can’t outsmart this virus by forcing our way to herd immunity through widespread infection because the number of infected people and number hospitalized who may die would be too high.”

The nuts and bolts of predictive modelling

Over the past year, the Brookhaven-UIUC team has been carrying out various projects related to a broader COVID-19 modeling effort. Previously, they modeled how the epidemic would spread through Illinois and the UIUC campus, and how mitigation efforts would impact that spread. Last May, they began this project to calculate the effect of population heterogeneity on the spread of COVID-19.

Several approaches already exist for modeling the effect of heterogeneity on epidemic dynamics, but they typically assume heterogeneity remains constant over time. So, for example, if you’re not socially active today, you won’t be socially active tomorrow or in the weeks and months ahead.

“Basic epidemiological models only have one characteristic time, called the generation interval or incubation period,” said Tkachenko. “It refers to the time when you can infect another person after becoming infected yourself. For COVID-19, it’s roughly five days. But that’s only one timescale. There are other timescales over which people change their social behavior.”

In this work, the team incorporated time variations in individual social activity into existing epidemiological models. While a complicated, multidimensional model is needed to describe each group of people with different susceptibilities to disease, they compressed this model into only three equations, developing a single parameter to capture biological and social sources of heterogeneity.

“We call this parameter the immunity factor, which tells you how much the reproduction number drops as susceptible individuals are removed from the population,” explained Maslov.

The reproduction number indicates how transmissible an infectious disease is. Specifically, the quantity refers to how many people one infected person will in turn infect. To estimate the social contribution to the immunity factor, the team leveraged previous studies in which scientists actively monitored people’s social behavior. They also looked at actual epidemic dynamics, determining the immunity factor most consistent with data on COVID-19-related hospitalizations, intensive care unit admissions, and daily deaths in NYC and Chicago. For example, when the susceptible number dropped by 10 percent during the early, fast-paced epidemic in NYC and Chicago, the reproduction number fell by 40 to 50 percent–corresponding to an estimated immunity factor of four to five.

“That’s a fairly large immunity factor, but it’s not representative of lasting herd immunity,” said Tkachenko. “On a longer timescale, we estimate a much lower immunity factor of about two. The fact that a single wave stops doesn’t mean you’re safe. It can come back.”

This temporary state of immunity arises because population heterogeneity is not permanent; people change their social behavior over time. For instance, individuals who self-isolated during the first wave–staying home, not having visitors over, ordering groceries online–subsequently start relaxing their behaviors. Any increase in social activity means additional exposure risk.

“The epidemic has been with us a year now,” said Maslov. “It’s important to understand why it has been here for such a long time. The gradual change in social behavior among individuals partially explains why plateaus and subsequent waves are occurring. For example, both cities avoided a summer wave but experienced a winter wave. We attribute the winter wave to two factors: the change in season and the waning of transient collective immunity.”

With vaccination becoming more widespread, the team hopes we will be spared from another wave. In their most recent work, they are studying epidemic dynamics in more detail. For example, they are feeding statistics from “superspreader” events–gatherings where a single infected person causes a large outbreak among attendees–into the model. They are also applying their model to different regions across the country to explain overall epidemic dynamics from the end of lockdown to early March 2021.

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This work was supported by the DOE Office of Science; University of Illinois System Office, the Office of the Vice-Chancellor for Research and Innovation, the Grainer College of Engineering, and the Department of Physics at UIUC; DOE Computational Science Graduate Fellowship; and National Science Foundation Faculty Early Career Development (CAREER) Program. This research was carried out as part of a CFN user program. The Illinois Department of Public Health, through a Data Use Agreement with Civis Analytics, supplied data for the calculations. The calculations were carried out on the Illinois Campus Cluster, a computing resource operated by the Illinois Campus Cluster Program in conjunction with the National Center for Supercomputing Applications, which is supported by funds from UIUC.

Brookhaven National Laboratory is supported by the U.S. Department of Energy’s Office of Science. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science.

Follow @BrookhavenLab on Twitter or find us on Facebook.

Media Contact
Ariana Manglaviti
amanglaviti@bnl.gov

Original Source

https://www.bnl.gov/newsroom/news.php?a=118757

Related Journal Article

http://dx.doi.org/10.1073/pnas.2015972118

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The Coming Of The Police State In America

The Coming Of The Police State In America

Authored by Jeffrey Tucker via The Epoch Times,

The National Guard and the State Police are now…

Published

18 hours ago

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March 9, 2024

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The Coming Of The Police State In America

Authored by Jeffrey Tucker via The Epoch Times,

The National Guard and the State Police are now patrolling the New York City subway system in an attempt to do something about the explosion of crime. As part of this, there are bag checks and new surveillance of all passengers. No legislation, no debate, just an edict from the mayor.

Many citizens who rely on this system for transportation might welcome this. It’s a city of strict gun control, and no one knows for sure if they have the right to defend themselves. Merchants have been harassed and even arrested for trying to stop looting and pillaging in their own shops.

The message has been sent: Only the police can do this job. Whether they do it or not is another matter.

Things on the subway system have gotten crazy. If you know it well, you can manage to travel safely, but visitors to the city who take the wrong train at the wrong time are taking grave risks.

In actual fact, it’s guaranteed that this will only end in confiscating knives and other things that people carry in order to protect themselves while leaving the actual criminals even more free to prey on citizens.

The law-abiding will suffer and the criminals will grow more numerous. It will not end well.

When you step back from the details, what we have is the dawning of a genuine police state in the United States. It only starts in New York City. Where is the Guard going to be deployed next? Anywhere is possible.

If the crime is bad enough, citizens will welcome it. It must have been this way in most times and places that when the police state arrives, the people cheer.

We will all have our own stories of how this came to be. Some might begin with the passage of the Patriot Act and the establishment of the Department of Homeland Security in 2001. Some will focus on gun control and the taking away of citizens’ rights to defend themselves.

My own version of events is closer in time. It began four years ago this month with lockdowns. That’s what shattered the capacity of civil society to function in the United States. Everything that has happened since follows like one domino tumbling after another.

It goes like this:

1) lockdown,

2) loss of moral compass and spreading of loneliness and nihilism,

3) rioting resulting from citizen frustration, 4) police absent because of ideological hectoring,

5) a rise in uncontrolled immigration/refugees,

6) an epidemic of ill health from substance abuse and otherwise,

7) businesses flee the city

8) cities fall into decay, and that results in

9) more surveillance and police state.

The 10th stage is the sacking of liberty and civilization itself.

It doesn’t fall out this way at every point in history, but this seems like a solid outline of what happened in this case. Four years is a very short period of time to see all of this unfold. But it is a fact that New York City was more-or-less civilized only four years ago. No one could have predicted that it would come to this so quickly.

But once the lockdowns happened, all bets were off. Here we had a policy that most directly trampled on all freedoms that we had taken for granted. Schools, businesses, and churches were slammed shut, with various levels of enforcement. The entire workforce was divided between essential and nonessential, and there was widespread confusion about who precisely was in charge of designating and enforcing this.

It felt like martial law at the time, as if all normal civilian law had been displaced by something else. That something had to do with public health, but there was clearly more going on, because suddenly our social media posts were censored and we were being asked to do things that made no sense, such as mask up for a virus that evaded mask protection and walk in only one direction in grocery aisles.

Vast amounts of the white-collar workforce stayed home—and their kids, too—until it became too much to bear. The city became a ghost town. Most U.S. cities were the same.

As the months of disaster rolled on, the captives were let out of their houses for the summer in order to protest racism but no other reason. As a way of excusing this, the same public health authorities said that racism was a virus as bad as COVID-19, so therefore it was permitted.

The protests had turned to riots in many cities, and the police were being defunded and discouraged to do anything about the problem. Citizens watched in horror as downtowns burned and drug-crazed freaks took over whole sections of cities. It was like every standard of decency had been zapped out of an entire swath of the population.

Meanwhile, large checks were arriving in people’s bank accounts, defying every normal economic expectation. How could people not be working and get their bank accounts more flush with cash than ever? There was a new law that didn’t even require that people pay rent. How weird was that? Even student loans didn’t need to be paid.

By the fall, recess from lockdown was over and everyone was told to go home again. But this time they had a job to do: They were supposed to vote. Not at the polling places, because going there would only spread germs, or so the media said. When the voting results finally came in, it was the absentee ballots that swung the election in favor of the opposition party that actually wanted more lockdowns and eventually pushed vaccine mandates on the whole population.

The new party in control took note of the large population movements out of cities and states that they controlled. This would have a large effect on voting patterns in the future. But they had a plan. They would open the borders to millions of people in the guise of caring for refugees. These new warm bodies would become voters in time and certainly count on the census when it came time to reapportion political power.

Meanwhile, the native population had begun to swim in ill health from substance abuse, widespread depression, and demoralization, plus vaccine injury. This increased dependency on the very institutions that had caused the problem in the first place: the medical/scientific establishment.

The rise of crime drove the small businesses out of the city. They had barely survived the lockdowns, but they certainly could not survive the crime epidemic. This undermined the tax base of the city and allowed the criminals to take further control.

The same cities became sanctuaries for the waves of migrants sacking the country, and partisan mayors actually used tax dollars to house these invaders in high-end hotels in the name of having compassion for the stranger. Citizens were pushed out to make way for rampaging migrant hordes, as incredible as this seems.

But with that, of course, crime rose ever further, inciting citizen anger and providing a pretext to bring in the police state in the form of the National Guard, now tasked with cracking down on crime in the transportation system.

What’s the next step? It’s probably already here: mass surveillance and censorship, plus ever-expanding police power. This will be accompanied by further population movements, as those with the means to do so flee the city and even the country and leave it for everyone else to suffer.

As I tell the story, all of this seems inevitable. It is not. It could have been stopped at any point. A wise and prudent political leadership could have admitted the error from the beginning and called on the country to rediscover freedom, decency, and the difference between right and wrong. But ego and pride stopped that from happening, and we are left with the consequences.

The government grows ever bigger and civil society ever less capable of managing itself in large urban centers. Disaster is unfolding in real time, mitigated only by a rising stock market and a financial system that has yet to fall apart completely.

Are we at the middle stages of total collapse, or at the point where the population and people in leadership positions wise up and decide to put an end to the downward slide? It’s hard to know. But this much we do know: There is a growing pocket of resistance out there that is fed up and refuses to sit by and watch this great country be sacked and taken over by everything it was set up to prevent.

Tyler Durden Sat, 03/09/2024 - 16:20

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Another beloved brewery files Chapter 11 bankruptcy

The beer industry has been devastated by covid, changing tastes, and maybe fallout from the Bud Light scandal.

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23 hours ago

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March 9, 2024

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Before the covid pandemic, craft beer was having a moment. Most cities had multiple breweries and taprooms with some having so many that people put together the brewery version of a pub crawl.

It was a period where beer snobbery ruled the day and it was not uncommon to hear bar patrons discuss the makeup of the beer the beer they were drinking. This boom period always seemed destined for failure, or at least a retraction as many markets seemed to have more craft breweries than they could support.

Related: Fast-food chain closes more stores after Chapter 11 bankruptcy

The pandemic, however, hastened that downfall. Many of these local and regional craft breweries counted on in-person sales to drive their business. 

And while many had local and regional distribution, selling through a third party comes with much lower margins. Direct sales drove their business and the pandemic forced many breweries to shut down their taprooms during the period where social distancing rules were in effect.

During those months the breweries still had rent and employees to pay while little money was coming in. That led to a number of popular beermakers including San Francisco's nationally-known Anchor Brewing as well as many regional favorites including Chicago’s Metropolitan Brewing, New Jersey’s Flying Fish, Denver’s Joyride Brewing, Tampa’s Zydeco Brew Werks, and Cleveland’s Terrestrial Brewing filing bankruptcy.

Some of these brands hope to survive, but others, including Anchor Brewing, fell into Chapter 7 liquidation. Now, another domino has fallen as a popular regional brewery has filed for Chapter 11 bankruptcy protection.

Overall beer sales have fallen.

Image source: Shutterstock

Covid is not the only reason for brewery bankruptcies

While covid deserves some of the blame for brewery failures, it's not the only reason why so many have filed for bankruptcy protection. Overall beer sales have fallen driven by younger people embracing non-alcoholic cocktails, and the rise in popularity of non-beer alcoholic offerings,

Beer sales have fallen to their lowest levels since 1999 and some industry analysts

"Sales declined by more than 5% in the first nine months of the year, dragged down not only by the backlash and boycotts against Anheuser-Busch-owned Bud Light but the changing habits of younger drinkers," according to data from Beer Marketer’s Insights published by the New York Post.

Bud Light parent Anheuser Busch InBev (BUD) faced massive boycotts after it partnered with transgender social media influencer Dylan Mulvaney. It was a very small partnership but it led to a right-wing backlash spurred on by Kid Rock, who posted a video on social media where he chastised the company before shooting up cases of Bud Light with an automatic weapon.

Another brewery files Chapter 11 bankruptcy

Gizmo Brew Works, which does business under the name Roth Brewing Company LLC, filed for Chapter 11 bankruptcy protection on March 8. In its filing, the company checked the box that indicates that its debts are less than $7.5 million and it chooses to proceed under Subchapter V of Chapter 11. 

"Both small business and subchapter V cases are treated differently than a traditional chapter 11 case primarily due to accelerated deadlines and the speed with which the plan is confirmed," USCourts.gov explained. 

Roth Brewing/Gizmo Brew Works shared that it has 50-99 creditors and assets $100,000 and $500,000. The filing noted that the company does expect to have funds available for unsecured creditors. 

The popular brewery operates three taprooms and sells its beer to go at those locations.

"Join us at Gizmo Brew Works Craft Brewery and Taprooms located in Raleigh, Durham, and Chapel Hill, North Carolina. Find us for entertainment, live music, food trucks, beer specials, and most importantly, great-tasting craft beer by Gizmo Brew Works," the company shared on its website.

The company estimates that it has between $1 and $10 million in liabilities (a broad range as the bankruptcy form does not provide a space to be more specific).

Gizmo Brew Works/Roth Brewing did not share a reorganization or funding plan in its bankruptcy filing. An email request for comment sent through the company's contact page was not immediately returned.

 

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Revving up tourism: Formula One and other big events look set to drive growth in the hospitality industry

With big events drawing a growing share of of tourism dollars, F1 offers a potential glimpse of the travel industry’s future.

Published

2 days ago

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March 8, 2024

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Sergio Perez of Oracle Red Bull Racing, right, and Charles Leclerc of the Scuderia Ferrari team compete in the Las Vegas Grand Prix on Nov. 19, 2023. Tayfun Coskun/Anadolu via Getty Images

In late 2023, I embarked on my first Formula One race experience, attending the first-ever Las Vegas Grand Prix. I had never been to an F1 race; my interest was sparked during the pandemic, largely through the Netflix series “Formula 1: Drive to Survive.”

But I wasn’t just attending as a fan. As the inaugural chair of the University of Florida’s department of tourism, hospitality and event management, I saw this as an opportunity. Big events and festivals represent a growing share of the tourism market – as an educator, I want to prepare future leaders to manage them.

And what better place to learn how to do that than in the stands of the Las Vegas Grand Prix?

A smiling professor is illuminated by bright lights in a nighttime photo taken at a Formula 1 event in Nevada.
The author at the Las Vegas Grand Prix. Katherine Fu

The future of tourism is in events and experiences

Tourism is fun, but it’s also big business: In the U.S. alone, it’s a US$2.6 trillion industry employing 15 million people. And with travelers increasingly planning their trips around events rather than places, both industry leaders and academics are paying attention.

Event tourism is also key to many cities’ economic development strategies – think Chicago and its annual Lollapalooza music festival, which has been hosted in Grant Park since 2005. In 2023, Lollapalooza generated an estimated $422 million for the local economy and drew record-breaking crowds to the city’s hotels.

That’s why when Formula One announced it would be making a 10-year commitment to host races in Las Vegas, the region’s tourism agency was eager to spread the news. The 2023 grand prix eventually generated $100 million in tax revenue, the head of that agency later announced.

Why Formula One?

Formula One offers a prime example of the economic importance of event tourism. In 2022, Formula One generated about $2.6 billion in total revenues, according to the latest full-year data from its parent company. That’s up 20% from 2021 and 27% from 2019, the last pre-COVID year. A record 5.7 million fans attended Formula One races in 2022, up 36% from 2019.

This surge in interest can be attributed to expanded broadcasting rights, sponsorship deals and a growing global fan base. And, of course, the in-person events make a lot of money – the cheapest tickets to the Las Vegas Grand Prix were $500.

Two brightly colored race cars are seen speeding down a track in a blur.
Turn 1 at the first Las Vegas Grand Prix. Rachel Fu, CC BY

That’s why I think of Formula One as more than just a pastime: It’s emblematic of a major shift in the tourism industry that offers substantial job opportunities. And it takes more than drivers and pit crews to make Formula One run – it takes a diverse range of professionals in fields such as event management, marketing, engineering and beyond.

This rapid industry growth indicates an opportune moment for universities to adapt their hospitality and business curricula and prepare students for careers in this profitable field.

How hospitality and business programs should prepare students

To align with the evolving landscape of mega-events like Formula One races, hospitality schools should, I believe, integrate specialized training in event management, luxury hospitality and international business. Courses focusing on large-scale event planning, VIP client management and cross-cultural communication are essential.

Another area for curriculum enhancement is sustainability and innovation in hospitality. Formula One, like many other companies, has increased its emphasis on environmental responsibility in recent years. While some critics have been skeptical of this push, I think it makes sense. After all, the event tourism industry both contributes to climate change and is threatened by it. So, programs may consider incorporating courses in sustainable event management, eco-friendly hospitality practices and innovations in sustainable event and tourism.

Additionally, business programs may consider emphasizing strategic marketing, brand management and digital media strategies for F1 and for the larger event-tourism space. As both continue to evolve, understanding how to leverage digital platforms, engage global audiences and create compelling brand narratives becomes increasingly important.

Beyond hospitality and business, other disciplines such as material sciences, engineering and data analytics can also integrate F1 into their curricula. Given the younger generation’s growing interest in motor sports, embedding F1 case studies and projects in these programs can enhance student engagement and provide practical applications of theoretical concepts.

Racing into the future: Formula One today and tomorrow

F1 has boosted its outreach to younger audiences in recent years and has also acted to strengthen its presence in the U.S., a market with major potential for the sport. The 2023 Las Vegas race was a strategic move in this direction. These decisions, along with the continued growth of the sport’s fan base and sponsorship deals, underscore F1’s economic significance and future potential.

Looking ahead in 2024, Formula One seems ripe for further expansion. New races, continued advancements in broadcasting technology and evolving sponsorship models are expected to drive revenue growth. And Season 6 of “Drive to Survive” will be released on Feb. 23, 2024. We already know that was effective marketing – after all, it inspired me to check out the Las Vegas Grand Prix.

I’m more sure than ever that big events like this will play a major role in the future of tourism – a message I’ll be imparting to my students. And in my free time, I’m planning to enhance my quality of life in 2024 by synchronizing my vacations with the F1 calendar. After all, nothing says “relaxing getaway” quite like the roar of engines and excitement of the racetrack.

Rachel J.C. Fu does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

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