A Blog by Jonathan Low


Mar 31, 2021

The 4th Covid Surge Is Here. Is the Healthcare System Ready This Time?

Yes, the healthcare system is ready. The vaccines have been remarkably effective - and the inoculation effort, now as many as 3 million a day - has been impressive. 

But as is so often the case with public health emergencies, keeping the latest surge at bay requires good policy as well as good medical practice. That means matching vaccine availability with variant outbreaks - and continuing to distance and wear masks for a few months more. JL

Zeynep Tufekci reports in The Atlantic:

Across the US, cases have started rising again. Hospitalizations are ticking up. We appear to be entering our fourth stage. (But) we now have a supply of efficacious vaccines being administered at an incredible clip. If we act quickly, this surge could be merely a blip. 73% of people over 65, and 36% of US eligible adults, have received at least one dose. Two weeks after even a single dose, the two mRNA vaccines were 80% effective in preventing infection. We match variant surges with vaccines and keep up mitigations a little longer. We have the vaccine supply and the infrastructure to do it. We just need to actAcross the United States, cases have started rising again. In a few cities, even hospitalizations are ticking up. The twists and turns of a pandemic can be hard to predict, but this most recent increase was almost inevitable: A more transmissible and more deadly variant called B.1.1.7 has established itself at the precise moment when many regions are opening up rapidly by lifting mask mandates, indoor-gathering restrictions, and occupancy limits on gyms and restaurants.

We appear to be entering our fourth surge.

The good news is that this one is different. We now have an unparalleled supply of astonishingly efficacious vaccines being administered at an incredible clip. If we act quickly, this surge could be merely a blip for the United States. But if we move too slowly, more people will become infected by this terrible new variant, which is acutely dangerous to those who are not yet vaccinated.

The United States has an advantage that countries such as Canada, France, Germany, and Italy, who are also experiencing surges from this variant, don’t. The Moderna, Pfizer, and Johnson & Johnson vaccines work very well against this variant, and the U.S. has been using them to vaccinate more than 3 million people a day. That’s more than 4 percent of our vaccine-eligible population every three days. An astonishing 73 percent of people over 65, and 36 percent of all eligible adults in the country, have already received at least one dose. More than 50 million people are now considered fully vaccinated, having received either their booster dose or the “one and done” Johnson & Johnson shot. Many states have already opened up vaccination to anyone over 16, and everyone eligible is expected to have a chance to get at least a first dose no later than May.

In addition, the United States has had one of the largest outbreaks in the world. This has caused us immense suffering and loss, but it also means that we are now less vulnerable to future waves. So far, 30 million people in the United States have had a confirmed SARS-CoV-2 infection, although the real (unmeasured) number is perhaps as high as 100 million. As expected, those people retain some level of immunity for a substantial amount of time. It’s hard to know exactly how long, because the virus is so new, but for SARS (the related coronavirus that almost sparked a pandemic in 2003), people who were infected retained an antibody response, and thus protection, for an average of two years. Though amazingly, the vaccines appear to provide better immunity than natural infection, those previously infected also gain defenses. Carefully done studies on large populations show a very low rate of reinfection for this coronavirus: less than 1 percent. Plus, many documented reinfections tend to be mild or asymptomatic, an unsurprising outcome given that in these cases the virus is no longer totally novel for the immune system, and thus not as catastrophic in its consequences.

It’s pretty clear that large numbers of people in the U.S. already are, or will soon be, protected from COVID-19’s more severe outcomes, such as death and hospitalization, which the vaccines reduce so close to zero that clinical trials have reported hardly any such cases. And it gets better: Yesterday, the CDC released real-life data showing that, just two weeks after even a single dose, the two mRNA vaccines were 80 percent effective in preventing infection. The effectiveness rose to 90 percent after the second, booster dose. People in the study were routinely tested regardless of whether they had symptoms, so we know that vaccines prevented not just symptomatic illness—the vaccine-efficacy rate reported in the trials—but any infection. People who are not infected by a virus cannot transmit it at all, and even people who have a breakthrough case despite vaccination have been shown to have lower viral loads compared with unvaccinated people, and so are likely much less contagious.

All of this doesn’t mean that there will be zero deaths or illnesses among the vaccinated. The elderly, who tend to have weaker immune systems, are especially prone to having vaccines fail. In nursing homes, even the common cold can cause deadly outbreaks. But for the vaccinated, the risk from COVID-19 clearly has become comparable to “baseline risk”—it’s not zero, but just like the risks presented by the flu and other viruses, it’s not something for which most of us would put our lives on hold.

How do we square all this good news with what happened during a White House briefing yesterday, when CDC Director Rochelle Walensky interrupted the flow, saying, “I’m going to lose the script,” and talked of “the recurring feeling I have of impending doom.” She was visibly emotional and her voice cracked as she said was “scared,” and pleaded with Americans to “hold on a little longer.”

I can’t read her mind, but if I were Walensky, I’d be scared because those who are not protected through vaccination or past infection are still at grave risk, a fact that may be overshadowed by all the good news. Even as our vaccines continue to work very well against it, the particular variant we’re facing in this surge is both more transmissible and more deadly for the unvaccinated.

Throughout this pandemic, Americans have become used to asking one another to pull together and enact mitigations for everyone’s benefit. One of the slogans for mask wearing was “My mask protects you, and your mask protects me.” Although we were always polarized, and the effects were always unequal—our mitigations helped those who could work from home more than the essential workers who made that possible—at least theoretically, we were all in it together, even if some of us did not act like it.

You see this appeal to the collective good in the many discussions around achieving herd immunity, too: a goal that will protect us all. That’s still true to some degree, for the future, but it was always an oversimplification. Now, with uneven but increasing rates of vaccination, understanding how those divisions work is even more important, starting with herd immunity.

Herd immunity is sometimes treated as a binary threshold: We’re all safe once we cross it, and all unsafe before that. In reality, herd immunity isn’t a switch that provides individual protection, just a dynamic that makes it hard for epidemics to sustain themselves in a population over the long term. Even if 75 percent of the country has some level of immunity because of vaccination or past infection, the remaining 25 percent remains just as susceptible, individually, to getting infected. And while herd levels of immunity will eventually significantly drive down the number of infections, this may not happen without the epidemic greatly “overshooting”—infecting people beyond the levels required for achieving herd immunity, somewhat like a fire burning at full force even though it is just about to run out of fuel.

Worse, people’s infection risks are not distributed evenly: Some people have lots of contacts, while others have a few. People are also embedded in different social networks: Some may have a lot of friends and family members who are immune, others not so much. Some work in jobs that increase their risk, others not so much. So it’s perfectly possible for a country as a whole to have herd immunity against a pathogen, but for outbreaks to happen among communities that have a lot of unvaccinated people among them. That’s happened in California, Michigan, and New York for measles among vaccine-resistant communities. In addition, this coronavirus is highly overdispersed. Infections occur in clumps. A single event can result in dozens or even hundreds of people being infected all at once in a super-spreader event.

Compared with previous surges, case-for-unvaccinated-case, this surge has the potential to cause more illness and more deaths, infecting fewer but doing more damage among them. We can also expect to see more younger, unvaccinated people falling sick and dying. We’ve observed this in other places, including the U.K. and Israel, which started vaccinating the elderly after B.1.1.7 had already taken hold and then had many younger victims. This variant is also very hard to dislodge; the U.K., for example, was able to avoid more catastrophic outcomes by delaying booster doses to cover more people initially, but still battled lengthy surges, as did Israel. Even with the U.K.’s ongoing vaccination campaign, which started in early December, almost 50,000 people in the country died from COVID-19 in just January and February this year, equal to nearly two-thirds of the total for all of 2020.

Other complications have arisen, too. In some places, we could be seeing what pandemic denialists have been calling “casedemics”—a term that (falsely) implies that the large number of cases amounted to no big deal. In the past, those deniers were wrong because case numbers and infection rates were leading indicators of later hospitalization and death rates. This time, in many places, case upticks may not result in measurable hospital outcomes, because so many elderly people are vaccinated. However, this surge can’t be dismissed as a “casedemic” either, because this virus causes lingering long-term effects—known as “long COVID”—for some portion of the younger population, too. This effect has been observed for other viral diseases, such as influenza and nonbacterial pneumonia, and is clearly an important consideration, especially when so many people are encountering a novel virus for the first time as adults.

While we don’t have extensive genomic surveillance, we do have some, and every indication is that the upticks in cases are happening in places with a high percentage of B.1.1.7 variant among reported coronavirus infections: Michigan, New Jersey, Philadelphia, Florida, Southern California, and few others. Tragically, some of those places also have great vaccine inequities. In Michigan, for example, as of mid-March, a mere 28 percent of Black people over 65 had received one dose of vaccine—a number as low as 15 percent in Detroit—even though more than 60 percent of all senior citizens in the state have been at least partially vaccinated. Similar inequities have been reported all over the country, with great disparities in vaccination rates especially among the elderly, who are more vulnerable to severe disease. Frontline and essential workers, who tend to be poorer and are more likely to be Hispanic or Black than the average American worker, also have varying levels of vaccine coverage from state to state.

The solution is obvious and doable: We should immediately match variant surges with vaccination surges that target the most vulnerable by going where they are, in the cities and states experiencing active outbreaks—an effort modeled on a public-health tool called “ring vaccination.” Ring vaccination involves vaccinating contacts and potential contacts of cases, essentially smothering the outbreak by surrounding it with immunity. We should do this, but on a surge scale, essentially ring-vaccinating whole cities and even states.

A vaccination surge means setting up vaccination tents in vulnerable, undervaccinated neighborhoods—street by street if necessary—and having mobile vaccination crews knock on doors wherever possible. It means directing supply to places where variants are surging, even if that means fewer vaccine doses for now in places with outbreaks under control. It doesn’t make sense to vaccinate 25-year-olds in places with very low levels of circulation before seniors and frontline workers in places where there is an outbreak.

Another sensible step would be to delay opening up—especially places with surges and especially for high-risk activities that take place indoors—until the next 100 million Americans are vaccinated, which could be done as quickly as in a single month. It makes no sense to rush to open everything now, when waiting a few weeks could protect so many. In the meantime, we need to protect frontline and essential workers by providing high-filtration masks and paid sick leave while targeting their workplaces with vaccination campaigns. We have already asked so much of them, and they have already suffered so much.

I understand the impatience with restrictions—I’m fed up and tired, too—but our restlessness risks creating one last set of victims who could easily be spared. We should not condemn anyone to be the last person to die unnecessarily in a war that we will win, and shortly. The vaccinated can clearly do more, and safely, especially two weeks after their final dose. But it’s a particularly perilous time for the unvaccinated, who deserve our attention, resources, and continued mitigation measures as appropriate.

More dangerous variants are going to be a huge problem around the world, too. Brazil is facing its own variant and surge, and is registering a record number of deaths day after day, as its hospital system faces a collapse from overload. Multiple countries in Europe are going into another round of shutdowns as they face B.1.1.7-driven surges without sufficient vaccine coverage or supply. Places like India that were relatively spared before are seeing a significant rise in cases and deaths, and once again, B.1.1.7 and other local variants appear to play a role. Many countries have yet to vaccinate a single person, and will now face potential surges driven by more difficult variants. In the HIV pandemic, we went through the same tragic moral failure: Poor countries didn’t get substantive supplies of effective—but expensive—antiviral therapies until almost 10 years after they became available in rich countries. Meanwhile, millions died.

Exponential growth—the hallmark of epidemics, but which the B.1.1.7 variant accelerates—is dangerous but also sensitive to small initial changes, giving an advantage to those who act quickly. A slight increase in transmissibility can make the difference between an epidemic petering out or being easy to control with a reasonable amount of mitigation measures, and that same epidemic ravaging a whole country. Starting vaccinations a few weeks earlier can make the difference between being able to largely outrun the virus and being swamped by its exponential growth instead

We know what we should do—match variant surges with vaccines and keep up our mitigations for just a little longer. We have the vaccine supply and the infrastructure to do it. We just need to act—now.


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