The big question for most people is how long are we going to have to isolate and how long will this pandemic last.
And, what’s coming next?
No one — not even health experts and epidemiologists — can tell you for sure. But it is possible to get an idea by looking at epidemiological information about the virus and looking at the experience in other countries that got hit by the virus first.
Here’s the difficult reality: we won’t be free from the risk of the virus until a sufficient number of people acquire immunity. And that will only happen when either a vaccine is developed or enough people have had Covid-19 and recovered.
The vaccine solution is obviously preferable, but it takes time to develop and sufficiently test a vaccine to make sure it’s both effective and safe.
Anthony Fauci, the American immunologist who serves as director of the National Institute of Allergy and Infectious Diseases and as a member of the White House Coronavirus Task Force, has said it could take a year and a half. With luck and international cooperation, it could be faster, but ignore the statements U.S. President Donald Trump has made about the vaccine being imminent. In fact, ignore everything Trump says about this virus.
One of the concerns with developing a vaccine is that the virus, officially known as SARS-CoV-2, might mutate, creating new strains that can bypass a vaccine. That’s why, for example, there’s no vaccine for the common cold, which is potentially caused by more than 200 virus strains.
But there’s good news about possible mutation of SARS-CoV-2. Scientists tracking the spread have found the virus is not mutating significantly, suggesting developing an effective vaccine could be less complicated. (Washington Post)
“At this point the mutation rate of the virus would suggest that the vaccine developed for SARS-CoV-2 would be a single vaccine, rather than a new vaccine every year like the flu vaccine.” – Peter Thielen, molecular geneticist at the Johns Hopkins University Applied Physics Laboratory in the Washington Post.
The less desirable path is that enough people contract and recover from the virus, thereby developing a “herd immunity.” The more people in a population who are immune, the harder it is for the virus to spread to others.
Medical professionals believe that people acquire immunity after recovering from the virus, but there are still a lot of unknowns.
This article from NPR — National Public Radio in the U.S. — discusses the immunity question.
So why not let a lot of people get infected to build up “herd immunity” quickly? The problem, obviously, is that many people would become seriously sick and overrun the healthcare system. About 15 percent of those with the virus require hospitalization.
“Flattening the curve” is all about slowing the rate of spread through social distancing and isolation. Slowing the spread helps to keep the number of cases to a level the medical system can handle by extending the time over which the curve proceeds, reducing the number of cases at the peak. It requires strong social distancing and isolation before the worst hits.
If the system becomes overwhelmed, many more people will die as overworked medical professionals have to choose who gets a ventilator and who doesn’t.
This article in Forbes, a U.S. business magazine, discusses three possible scenarios: doing nothing; mitigating the spread by isolating those at greatest risk; or suppression — closing schools and distancing everyone. The article draws on a recent paper from Imperial College COVID-19 Response Team in the United Kingdom.
Here in Canada, the response leans towards mitigating and suppression. In the U.S., responses in different states are all over the map with some governors imposing tough suppression measures and some doing almost nothing.
The problem is that infectious diseases expand exponentially rather than linearly. This article, “The Promising Math Behind ‘Flattening the Curve’” in Wired by Rhett Allain, an associate professor of physics at Southeastern Louisiana University, explains the math.
The good news, he says, is that after exponential growth at first, the rate of growth does flatten and decline.
“Reduce this spike and you spread the infections over a longer period of time. That might not sound great as we’re all getting stir-crazy indoors. But it means you avoid overburdening the health care system. Reduce the growth rate, stretch out the curve, and you save lives.” — Rhett Allain
This article from LiveScience,” Coronavirus: What is ‘flattening the curve,’ and will it work?” explains the concept of “flattening the curve” for those who would rather not wade through the math.
This article in the Washington Post uses animated graphics to simulate how diseases spread and how immunity develops. The Post also has a simulation showing how a population becomes infected, but recovers after enough people have had the virus.
Back to the original questions — how long will this last and what’s coming next?
Unfortunately, we are now in the phase of exponential growth in infections. Sadly, many people will become very sick and roughly 2 percent of people with the illness will die. Based on the experiences in Asia and Europe, we can expect weeks of exponential growth before it starts to level off and decline.
We can probably expect restrictions to be relaxed when the rate of new infections drops enough. But as people become complacent again, restrictions will resume to suppress new spreads.
So it probably won’t be a case of full isolation for a year and a half, but we may be living with the virus for many months as restrictions are tightened, relaxed and tightened again.