I was asked recently when life might return to normal. The question is simple but the answer is complex, with many knowns, lots of known unknowns, and some unknown unknowns. But I'll give it my best shot.
To get the fatality rate down to flu-like levels would require that we cut Covid-19 fatalities down by a factor of 5.
Since I'm human (and thus want my life back), I might be biased toward optimism.
Here's one way to think about it: Is there another infection that causes sickness and death at levels that we tolerate? The answer, of course, is 'yes': influenza.
According to the Centers for Disease Control, from 2010 to 2019, an average of 30 million Americans had the flu each year, leading to an annual average of 37,000 deaths. This works out to an infection-fatality rate, or IFR, of 0.12 percent. We've tolerated that level of illness death from influenza for a century.
Before going on, let's get one thing out of the way: Back in March, Covid-19 wasn't, as some maintained, "like the flu," and it still isn't. Since then, the U.S. has had 3.9 million confirmed Covid-19 cases and 140,000 deaths, for an IFR of 3.6 percent. Taking all the cases — including asymptomatic patients and those with minimal symptoms who were never tested for Covid-19 — into account, the real IFR is probably 0.6 percent, or roughly 5 times that of the flu.
Nonetheless, even a partly effective vaccine, combined with moderately effective medications, could bring Covid-19 numbers down to a tolerable, flu-like, threshold. It's a goal that seems within our reach.
Chronic mask-wearing and physical distancing are not my idea of normal, nor, I would venture to guess, would most other Americans consider these desirable states in which to live. We need both now to achieve some semblance of normalcy, but they're decidedly not normal life. My notion of normal: daily life with no or minimal mask wearing, open restaurants and bars, ballparks with fans, and theaters with audiences.
My projection for when we might get there: perhaps a year from now.
To get the fatality rate down to flu-like levels would require that we cut Covid-19 fatalities down by a factor of 5, via some combination of fewer symptomatic cases and a lower chance that a symptomatic patient will go on to die. How might that happen?
First, we have to make some impact on young people – getting them to follow the public health directives at higher rates than they are currently. The main reason we need to push younger people to stay safe is that they can spread Covid-19 to vulnerable people (those who are older, with underlying health problems). But, once the most vulnerable are protected (through the deployment of some combination of effective medications and a vaccine), the fact that some young people aren't acting safely – or maybe won't take a vaccine themselves – wouldn't cause so much concern. The key is whether the people at highest risk for bad outcomes are protected.
Then there's the vaccine. The first principle: We don't need a 100 percent-effective vaccine injected into 320 million deltoid muscles (in the U.S. alone). Thank God, since it's fanciful to believe that we can have a vaccine that's 100 percent effective, universally available by next summer, and that each and every American agrees to be vaccinated.
How are we doing in our vaccine journey? We've been having some banner days lately, with recent optimistic reports from several of the vaccine companies. In one report, the leading candidate vaccine, the one effort being led by Oxford University, led to both antibodies and a cellular immune response, a very helpful belt-and-suspenders approach that increases the probability of long-lasting immunity. This good news comes on the heels of the positive news regarding the American vaccine being made by Moderna earlier in July.
While every article about vaccines sounds the obligatory cautionary notes, to date we've checked every box on the path to a safe and effective vaccine. We might not get there, but most experts are now predicting an FDA-approvable vaccine (more than 50 percent effective with no show-stopping side effects) by early 2021.
It is true that we don't know how long immunity will last, but that can be a problem to solve later. In this area, time is our friend. If we can get to an effective vaccine that lasts for a year or two, over time we should be able to discover strategies (more vaccine boosters, new and better medications) to address the possibility of waning immunity.
All things considered, I'm going to put my nickel down on the following optimistic scenario: we'll have one, and likely several, vaccines that have been proven to be more than 50 percent effective and safe by January, 2021.
If only that were the finish line.
Once we vaccinate a large fraction of high-risk patients, having a moderate number of unvaccinated people running around won't pose as much threat.
The investments in manufacturing and distribution should pay off, but it's still inconceivable that we'll be able to get vaccines to 300 million people in three to six months. For the 2009 Swine Flu, we managed to vaccinate about 1 in 4 Americans over six months.
So we'll need to prioritize. First in line will likely be the 55 million Americans over 65, and the six to eight million patient-facing healthcare workers. (How to sort priorities among people under 65 with "chronic diseases" will be a toughie.) Vaccinating 80-100 million vulnerable people, plus clinicians, might be achievable by mid-21.
If we can protect vulnerable people with an effective vaccine (with the less vulnerable waiting their turn over a subsequent 6-12 month period), that may be enough to do the trick. (Of course, vulnerable people may also be least likely to develop immunity in response to a vaccine. That could be an Achilles' heel – time will tell.)
Why might that be enough? Once we vaccinate a large fraction of high-risk patients, having a moderate number of unvaccinated people running around won't pose as much threat. Since they're at lower risk, they have a lower chance of getting sick and dying than those who received the vaccine first.
We're likely to have better meds by then, too. Since March, we've discovered two moderately effective medications for Covid-19 — remdesivir and dexamethasone. It seems likely that we'll find others by next summer, perhaps even a treatment that prevents patients from getting ill in the first place. There are many such therapies, ranging from zinc to convalescent plasma, currently being studied.
Moreover, we know that hospitals that are not overrun with Covid-19 have lower mortality rates. If we've gotten a fairly effective vaccine into most high-risk people, the hospitals are unlikely to be overwhelmed – another factor that may help lower the mortality rate to flu-like levels.
All of these factors – vaccination of most vulnerable people, one or two additional effective medications, hospitals and ICU's that aren't overwhelmed – could easily combine to bring the toll of Covid-19 down to something that resembles that of the flu. Then, we should be able to return to normal life.
Whatever the reason, if enough people refuse the vaccine, all bets are off.
What do I worry about? There's the growing anti-vaxxer movement, for one. On top of that, it seems that many Americans worry that a vaccine discovered in record speed won't be safe, or that the FDA approval process will have been corrupted by political influences. Whatever the reason, if enough people refuse the vaccine, all bets are off.
Assuming only high-risk people do get vaccinated, there will still be cases of Covid-19, maybe even mini-outbreaks, well into 2021 and likely 2022. Obviously, that's not ideal, and we should hope for a vaccine that results in the complete eradication of Covid-19. But the point is that, even with flu-like levels of illness and death, we should still be able to achieve "normal."
Hope is not a strategy, as the saying goes. But it is hope, which is more than we've had for a while.