Pandemic Predictions

When will we be able to come out of our pandemic isolation and resume life with high confidence that we will not contract Covid-19? We all want to know, but predicting the future is always an uncertain endeavor. Using science to predict the end of a pandemic one might best be guided by the adage “plan for the worst and hope for the best.” In that spirit today I offer two different slants on pandemic prediction. 

The first is written by a friend, Bruce Chassy. Dr. Chassy holds a Ph.D. in Biochemistry and Molecular Biology from Cornell. He spent 21 years as a researcher at NIH and 23 years at the University of Illinois. This came to me (as well as the link to the more optimistic article below it) in email and is reproduced with permission:

What follows is a long post about where I think we are at in this pandemic. As you read, keep in mind that more and better therapies and vaccines could lead to a quicker and more favorable outcome. How about a pill that cures Covid-19?  It could happen.  What follows is based on where we are today, hopefully that will change for the better.

There was a story on one of the major networks yesterday about a documented case of someone who received the first vaccination on December 19th and now has a confirmed case of Covid-19.

95% means 19 out of 20 people are protected.  Somebody has to be the 20th and after hiding from SARs-CoV-2 for almost a year I don’t want it to be me.  Also unknown is whether a vaccinated person can contract and transmit to others without being ill.

So when can we
 get together?  When 70-80% of the population is vaccinated and new infection rates have crashed to almost nothing is what I am waiting for.  Do the math.  There are ~330 million Americans. If 100M are vaccinated in the first hundred days and 30 million have post-infection immunity, that amounts to a 40% immunity level.  If we assume these are non-spreaders then we would need to vaccinate another 100 million to reach 70% immunity.  That would crash the new infection rate pretty effectively.  It’s the low end of “herd immunity.”  If 100 days gets up to 100M vaccinated as Biden hopes,  and 200 days gets us to 200M, that will be sometime in early AUGUST… Approval of additional vaccines and significant increases in the rate of vaccination could also help control the pandemic.  The bottom line is don’t expect to be socializing in restaurants and bars for a long time yet.  

Herd immunity will not mean that Covid goes away.  It will be reduced to scattered cases and possibly isolated outbreaks, 
which, if not controlled, will could lead to pockets of epidemic spread.  Covid-19 could easily become like seasonal influenza or common colds.  It could be eradicated but it won’t be. Had the US relied on natural herd immunity to control the pandemic around 3-5 million might have perished. New drugs and antibody therapy might have reduced the carnage.  Historians would have named it Trump’s Holocaust. 

The real danger here is that the more people who contract the disease the greater the chance for adverse mutations.  We have already heard about fast spreading strains.  Should one of those strains not be prevented by the current vaccines, we will be in a lot of trouble.  A more lethal mutation could be even worse.  That is why it was so important to have controlled SARs-CoV-2 as early as possible.  Trump stole that opportunity from our public health experts. Trump couldn’t possibly have understood when the experts explained “More Cases” =  “greater chance for disastrous mutations” because his evaluation was there was nothing in it for him.  Anything that hurt the economy could hurt his chances for re-election.  It’s water under the bridge, but had he mobilized the public health system in January 2020, closed the borders, applied the defense mobilization acts and committed to a national emergency effort to control Covid-19, we would not be where we are now.  And where we are could be the edge of a very slippery slope because millions of cases mean millions of mutations.  Genetics is a numbers game and organisms that multiply quickly change quickly.

As regards controlling Covid-19 Winston Churchill may have said it best:

“This is not the end, this is not even the beginning of the end, this is just perhaps the end of the beginning.”

For counterpoint, a “hope for the best” point of view, Professor Chassy offered a link to David Leonhardt’s column in the NYTimes from January 18th entitled “Good morning. We explain why the vaccine news is better than you may think.” I take the liberty to reproduce it here:

‘We’re underselling the vaccine’
Early in the pandemic, many health experts — in the U.S. and around the world — decided that the public could not be trusted to hear the truth about masks. Instead, the experts spread a misleading message, discouraging the use of masks.
Their motivation was mostly good. It sprung from a concern that people would rush to buy high-grade medical masks, leaving too few for doctors and nurses. The experts were also unsure how much ordinary masks would help.
But the message was still a mistake.
It confused people. (If masks weren’t effective, why did doctors and nurses need them?) It delayed the widespread use of masks (even though there was good reason to believe they could help). And it damaged the credibility of public health experts.
“When people feel as though they may not be getting the full truth from the authorities, snake-oil sellers and price gougers have an easier time,” the sociologist Zeynep Tufekci wrote early last year.
Now a version of the mask story is repeating itself — this time involving the vaccines. Once again, the experts don’t seem to trust the public to hear the full truth.
This issue is important and complex enough that I’m going to make today’s newsletter a bit longer than usual. If you still have questions, don’t hesitate to email me at
‘Ridiculously encouraging’
Right now, public discussion of the vaccines is full of warnings about their limitations: They’re not 100 percent effective. Even vaccinated people may be able to spread the virus. And people shouldn’t change their behavior once they get their shots.
These warnings have a basis in truth, just as it’s true that masks are imperfect. But the sum total of the warnings is misleading, as I heard from multiple doctors and epidemiologists last week.
“It’s driving me a little bit crazy,” Dr. Ashish Jha, dean of the Brown School of Public Health, told me.
“We’re underselling the vaccine,” Dr. Aaron Richterman, an infectious-disease specialist at the University of Pennsylvania, said.
“It’s going to save your life — that’s where the emphasis has to be right now,” Dr. Peter Hotez of the Baylor College of Medicine said.
The Moderna and Pfizer vaccines are “essentially 100 percent effective against serious disease,” Dr. Paul Offit, the director of the Vaccine Education Center at Children’s Hospital of Philadelphia, said. “It’s ridiculously encouraging.”
The details
Here’s my best attempt at summarizing what we know:
The Moderna and Pfizer vaccines — the only two approved in the U.S. — are among the best vaccines ever created, with effectiveness rates of about 95 percent after two doses. That’s on par with the vaccines for chickenpox and measles. And a vaccine doesn’t even need to be so effective to reduce cases sharply and crush a pandemic.If anything, the 95 percent number understates the effectiveness, because it counts anyone who came down with a mild case of Covid-19 as a failure. But turning Covid into a typical flu — as the vaccines evidently did for most of the remaining 5 percent — is actually a success. Of the 32,000 people who received the Moderna or Pfizer vaccine in a research trial, do you want to guess how many contracted a severe Covid case? One.Although no rigorous study has yet analyzed whether vaccinated people can spread the virus, it would be surprising if they did. “If there is an example of a vaccine in widespread clinical use that has this selective effect — prevents disease but not infection — I can’t think of one!” Dr. Paul Sax of Harvard has written in The New England Journal of Medicine. (And, no, exclamation points are not common in medical journals.) On Twitter, Dr. Monica Gandhi of the University of California, San Francisco, argued: “Please be assured that YOU ARE SAFE after vaccine from what matters — disease and spreading.”The risks for vaccinated people are still not zero, because almost nothing in the real world is zero risk. A tiny percentage of people may have allergic reactions. And I’ll be eager to see what the studies on post-vaccination spread eventually show. But the evidence so far suggests that the vaccines are akin to a cure.
Offit told me we should be greeting them with the same enthusiasm that greeted the polio vaccine: “It should be this rallying cry.”
The costs of negativity
Why are many experts conveying a more negative message?
Again, their motivations are mostly good. As academic researchers, they are instinctively cautious, prone to emphasizing any uncertainty. Many may also be nervous that vaccinated people will stop wearing masks and social distancing, which in turn could cause unvaccinated people to stop as well. If that happens, deaths would soar even higher.
But the best way to persuade people to behave safely usually involves telling them the truth. “Not being completely open because you want to achieve some sort of behavioral public health goal — people will see through that eventually,” Richterman said. The current approach also feeds anti-vaccine skepticism and conspiracy theories.
After asking Richterman and others what a better public message might sound like, I was left thinking about something like this:
We should immediately be more aggressive about mask-wearing and social distancing because of the new virus variants. We should vaccinate people as rapidly as possible — which will require approving other Covid vaccines when the data justifies it.
People who have received both of their vaccine shots, and have waited until they take effect, will be able to do things that unvaccinated people cannot — like having meals together and hugging their grandchildren. But until the pandemic is defeated, all Americans should wear masks in public, help unvaccinated people stay safe and contribute to a shared national project of saving every possible life.

I want to close today with something fun. For years now one of my favorite things has been the camaraderie of Sea Chanty singing. Recently, there has been renewed interest in Sea Chanty singingspurred by TikTok and longing for community made more poignant by pandemic isolation. At the link that follows watch a one minute video that combines Sea Chanty singing and vaccine science. It’s a hoot. Definitely worth your minute::

Keep to the high ground,