- Virus – a type of germ that consists solely of a bit of genetic material (DNA or RNA) wrapped in a protein coat. The coat gets the genes into the target cell where the genes force the cell to make zillions of new viruses, and on it goes.
- Coronavirus – a species name of a number of different viruses. Called corona because its protein coat is studded with spike shapes that form a crown, halo, or corona of spikes
- SARS-CoV-2 – the specific name of the new coronavirus
- COVID-2019 – the name of the illness that the new coronavirus is causing
- Endemic – an illness always present in a region. One could say strep throat is endemic in the US
- Epidemic – a sudden burst of an illness that comes and goes over a limited time
- Pandemic – an epidemic that bursts across the world not just one region
- Spreadability – how contagious is the disease, how many people will end up infected
- Severity – what harm does the disease cause, in terms of how sick you get and how many it will kill
A New Strategy – From Testing to Universal Action
When the SARS-CoV-2 virus first began appear in America, the initial strategy had to be focused on finding out where it was with the goal of keeping it from spreading.
During these initial weeks, the only way to execute this critical strategy was to do testing of everyone who might have COVID-19, in order to discover where the first cases were emerging, with the ultimate goal of keeping the SARS-CoV-2 from spreading from its initial landing sites. Tragically, this strategy never stood a chance, because our nation failed to distribute the tests necessary to do this plan. As a result of not having the test kits to stop the initial spread, the virus, as we all know, has spread.
The SARS-CoV-2 virus is now in every state. It certainly is here in Ohio, in all our neighborhoods. And as a result, the nation’s top health officials have begun proposing a new strategy: accepting the evident reality that the virus has spread, and moving now to limit new cases across every neighborhood, independent of testing. To be clear, testing still remains important, but it is shifting from helping us know if and where the virus has arrived, and now will be serving to identify if a person with a serious lung infection has this virus.
Studies will continue, using testing, to find out more details of major questions such as how many people infected with the virus have no symptoms, age distributions, etc.
But now that the pandemic is come to full bloom, (see more details in Spreadability below), it is no longer helpful to have everyone with symptoms or those who are well but contacted, tested.
In this new stage of our strategy, it is important to know that testing comes at a cost to the health care system. Gathering people with higher risk of being infected, that is those seeking testing, a large number of health care workers are obligated to obtain the tests, and to use protective gear to be in contact with those tested. Now that mass testing is losing its value, the allocation of health care workers to mass testing sites, using up supplies such as masks in critically short supply, is making the new urgency, managing those critically ill more difficult.
With this new reality in mind, we are joining with the national health experts in urging people who have mild symptoms, even symptoms consistent with COVID-19, to simply self-quarantine, and not seek testing.
A word on this new strategy. Consider the 80% of cases that never require any medical treatment, the 80% of COVID-19 cases that are mild and never lead to hospitalization. Consider the treatment plan should a person with mild illness be tested, or not be tested. If such a person is tested and found positive, the treatment plan will be have that person quarantine at home. Now, if such a person is tested and found negative, then that person will still be advised to stay at home, because everyone is being asked to stay at home and socially distant.
This does not mean no one with mild disease should be tested. The main people with mild illness who still need testing are those who have an urgent need to still be working outside the home, people such as myself and all other health care workers, or those working in groceries and pharmacies, and other such workers.
A reminder on the meaning of mild illness. A case of COVID-19 is considered mild if the person infected does not require oxygen to breathe adequately.
Some New Patterns – News for Young Adults and for all Men
It is worth reminding ourselves that the virus, SARS-CoV-2, first infected humanity just 4 months ago, every bit of information about the illness it causes, COVID-2 is only 4 months old, and so it has to be that we are still learning how it infects, and who it infects.
The data are preliminary, but we are seeing a pattern emerging that men are at greater risk than women. A recent report in The NY Times laid out what we know: https://www.nytimes.com/2020/03/20/health/coronavirus-italy-men-risk.html
And here are the highlights on the male risk from COVID-19:
- Men clearly were more likely to die than women in other new coronavirus infections, SARS and MERS.
- In Italy 58% of all those infected were male
- In Italy 70% of all deaths from COVID-19 were in men
- In China, the chance of a man dying from COVID-19 was 2.8% and for women was 1.7%
- Of note the pattern of excessive male death appears only after age 50
We have no idea why these patterns have emerged, but some guesses include:
- Men smoke more than women, in China the rates are 50% v 3% and in Italy 30% v. 19%, and smoking makes COVID-19 worse
- Men develop high blood pressure earlier in life than women, and this makes COVID-19 worse
- Men develop cardiovascular disease earlier in life than women, and this makes COVID-19 worse.
For Young Adults
A disturbing pattern of more young adults (less than 65 years olds) having lots of COVID-19 infections, and having more serious disease than expected. This morning the CDC reported that 48% of ICU admissions for COVID-19 are under 65 years old, and a full fifth of COVID-19 fatalities.
The main point to be made here is that young adults do appear to be getting infected and more severely infected in our American experience of this disease, than we have seen elsewhere.
However, even as recently as March 16, the Imperial College of London (see more below) has documented that across the globe, the chance of a 20-29 year old with COVID-19 needing any hospital care is 1.2%, and that only 5% of them hospitalized will need an ICU, and overall people in their 20’s have a 0.03% of dying, which is a very, very reassuring number for people in their 20’s.
So although the pattern for men over 50 is emerging as a more and more reliable risk factor, the very recent observation that many young adults in the US are getting sick may not be a pattern that holds up over time, let us hope not.
The Report From The Imperial College Of London, March 16, 2020
The Imperial College of London (ICL) is highly regarded as one of the world’s leading centers of epidemiologic science. If you want to know how a disease spreads, how it kills, what can stop it, the ICL is one the most trusted places to look for answers.
So the whole world anticipated their report, which came out on March 16, the link above gets you to the whole report, which is focused on what sort of steps short of vaccine or medication, will best stop this virus, and save the most lives.
Along the way, the paper presents absolutely terrific information on basic properties of the COVID-19 pandemic.
Here are some highlights.
On COVID-19 Spreadability
The report defines three places where a person can catch COVID-19: home, work or school, random contact in the community. A wide variety of variables were taken into account, such as the estimate that perc capita contacts were double in school than elsewhere, and found that the chance of catching COVID-19 across a nation was about equal in these three settings, that is, before any isolation measures are take, if nothing is done:
- One third of COVID-19 cases are caught in the home
- One-third of COVID-19 cases are caught at school or work
- One-third of COVID-19 cases are caught randomly outside the home, school or work
The authors found the actual average time from catching the SARS-CoV-2 virus to having symptoms of the COVID-19 illness was 5.1 days, making the incubation period about 5 days, typically.
A big question is when does someone with COVID-19 become contagious? Here is their answer:
- If you get COVID-19 symptoms, you become contagious about 12 hours before the first symptom, or, typically, 4 days after you catch the SARS-CoV-2 virus
- If you catch the SARS-CoV-2 but never get sick, then you become contagious about 4.6 days after you catch the virus, even if you never get sick.
- They find that infected people with symptoms are 50% more contagious than people without symptoms.
The key number that defines the spreadability of the SARS-CoV-2 is the R0, the reproducibility number, frequently discussed on these posts. This is the average number of people someone infected with the SARS-CoV-2 virus will spread the disease to. This number can change if cases are isolated, of course. But this report asks what is the R0 for SARS-CoV-2 virus, if nothing is done, and they put their estimate for R0 at 2.4, but model spread if it really is somewhere between 2.0-2.6.
The R0 defines how wild the wildfire of viral spread will heat up to. Imagine an uncontrolled outbreak has an R0 of 2.0, that means after 10 cycles of spread, one person will become about 1,000 cases, and after 20 cycles of spread one person will spread it to 1 million people. If the R0 just goes up to 2.6, those numbers go to 14,000, and 200 million!
If taking no action the R0 for SARS-CoV-2 virus really is 2.4, then one person spreads it to an average of 2.4 and they spread it each to the same number, and if that happens 10 rounds, one case becomes about 6,000 cases and after 20 rounds, 40 million cases. Keep in mind that this is the level of spread from one person if no actions are taken to limit the spread, which is no longer the case in Ohio or much of the United States.
The typical country is expected to have the number of cases rise exponentially, if not contained, and this has been true across the world. And no surprise. If one person infects more than one person and that happens over and over, the result is always an exponential rise.
On COVID-19 Severity
The ICL report also contains a wealth of information about how sick people with COVID-19 get.
How many cases are diagnosed by testing? Even in a heavily tested nation such as China, they estimate 40-50% of cases never get diagnosed. That number is far greater in countries with less testing, and the US has tested a smaller proportion of its population than any other advanced nation.
Once a country is on alert, what’s the chance someone with symptoms will indeed isolate themselves? Across the world that number stands at two thirds. And they tend to do so usually within one day of first symptoms.
How long is an infected person sick before they deteriorate to hospital level illness? The average time here is about 5 days.
How many people with infected (includes everyone with no symptoms) with infection will need a hospital? That number currently stands at 4.4%, but age is a huge variable. The chance any child with this infection will need a hospital is about 0.2%, very slight. Here it is by decade of age:
- 20’s 1.2%
- 30’s 3.2%
- 40’s 4.9%
- 50’s 10.2%
- 60’s 16.6%
- 70’s 24.3%
- 80’s 27.3%
So hospitalization risk jumps considerably over age 50, and goes to about 25% of all infected at age 70 and up.
How many people sick enough with COVID-19 to require a hospital will require critical care (on a ventilator of heart-lung machine)? That number currently stands at 30%, but age is a huge variable. The chance any child with this infection will need a hospital is about 5%. Here it is by decade of age:
- 20’s 5%
- 30’s 5%
- 40’s 6.3%
- 50’s 12.2%
- 60’s 27.4%
- 70’s 43.2%
- 80’s 70.9%
So if sick enough to require oxygen, ie hospital care, the chance of needed intubation, i.e critical care, is goes over 10% at age 50, and becomes a vast majority over age 80.
How many people sick with COVID-19 will not survive their illness? This group in London puts a global mortality rate currently at 0.9%, well below the WHO estimate of 3.4% . The chance any child with this infection will not live is incredibly remote, some series report none have died under age 9, the London group estimates mortality for 0-9 years old at 0.002% or about 2 in 100,000 cases, nearly zero.
Here is the mortality rate by decade of age
- 20’s 0.03%
- 30’s 0.08%
- 40’s 0.15%
- 50’s 0.60%
- 60’s 2.2%
- 70’s 5.1%
- 80’s 9.3%
The risk of mortality remains very strongly correlated to age, youth is protective.
On COVID-19 Immunity
The Imperial College of London team finds that there is good evidence that once you recover from COVID-19 you cannot get it again, at least for the short term, we do not know if immunity lasts years.
How Can We Stop this Epidemic without Drugs or Vaccines?
Now we turn our attention to how the London Report looks at 5 interventions:
- Isolate healthy infected cases in the home for 7 days
- Quarantine all household members where a case is isolated for 14 days
- Social distancing of only those over 70 years old
- Social distance everyone
- Close schools and universities
The report makes a crucial distinction in stopping the epidemic, there are three choices:
- Do nothing
- Actually stop all further spread, this is technically known as suppression
- Don’t stop the spread, but slow it down, this is technically known as mitigation.
The United States has rejected the ideas of doing nothing and embraced slowing the spread, or mitigation. A decision has also been made to not try to stop the spread, or suppress or contain the epidemic, which has been achieved by most nations attempting control in East Asia.
The report observes that the mix of interventions most likely to prevent the most deaths if only adopted for 3 months, (NOT the most cases) , is a combination of Case Isolation at Home, Voluntary Home Quarantine of all Home Contacts with a Case, and Social Isolation of those Over 70 Years Old. This strategy would prevent about 50% of deaths in the US. Curiously if a nation simply closes schools, this strategy is estimated to prevent only 2% of deaths. Also curiously, using the three part strategy (Case at home, other in that home at home, social distancing 70+ y/o’s) and adding school closures drops the number estimated to die from COVID-19 from around 50% to around 30%. This is because every strategy of isolation comes at some cost, they estimate closing schools will increase home-based contacts with the virus by 50% for example. But the story is complex, because school closures are an important long-term strategy to reduce number of cases over the long-term.
Ideally, the London Report recommends that a combination of three strategies until a medication or vaccine is in use:
- Universal social distancing, for everyone in the nation, to as great an extent possible, obviously excluding workers in vital sectors such as health, grocery, pharmacy
- Isolation of cases
- School and university closure.
Should a nation achieve these three goals, the London Report suggests actual suppression might occur, that is the virus will no longer spread.
How long will these strategies need to be maintained?
This all depends on the goal of the nation- full suppression, ending all spread, or slowing spread, and now long the nation is willing to keep the epidemic at bay.
Should no medication prove effective and a vaccine takes 18 months to develop, these measures would work best if they were in place the full 18 months, but the Report finds that much of the benefit would accrue if kept in place for 12 months.
Some strategies that may get around a year of this situation discussed included:
- Regionalizing these three strategies, only imposing them in states where the epidemic is a problem. This is the current American approach
- As noted above, only holding to these steps for 3 months could reduce death by 50% and ICU use by 67%.
The Report confirms our impression that if any such strategies are put in place it takes 2-3 weeks to see cases, deaths, and ICU use drop.
THE FINAL PLEA from the Imperial College of London is that even though mitigation can cut numbers of death in half, and ICU use by two-thirds, simply slowing the spread of the virus in the US will still leave over 1 million dead and our health system dramatically overwhelmed. They therefore conclude that nations should only seek suppression, actual end of transmission of the virus.
It simply spreads to easily, makes too many people critically ill, and causes too much death to let it spread at all. The report also recognizes no nation has ever sustained a level of suppression necessary to stop the spread for such a sustained period of time, such as 12 or 18 months.
- The COVID-19 Pandemic is a true danger, we all now know this. It spreads rapidly, it is poised to make very large numbers of people critically ill and cost many people their life.
- In the United States, the virus is already quite widespread. Aside from specific studies to understand the spread, testing is losing its value in those not needing hospitalization. People with fever, sore throat, and/or cough, without a runny nose should now assume they need to be isolated at home, with their families and household, for 14 days, and NOT SEEK TESTING.
- As of now, testing should be reserved for those ill enough to require oxygen to breathe.
- Our office will continue to advise people who are mildly ill with the symptoms noted, which are suggestive of COVID-19, to stay at home and not come to the office, or an ER. We remain available to families in our practice in such a situation via AP Televisits, an easy and effective way to get medical advice from us, your doctors.
- Evidence is tilting quite a bit towards the sense that men over 50 are at greater risk than women over 50. Smoking is a risk factor.
- The Report from the Imperial College of London presents a treasure of information, some of it listed above. The full report is here.
- There are so many valuable insights from this outstanding epidemiologic report. This virus spreads well, people get contagious about 4 and half days after the virus infects, People who recover are likely immune and not able to get it again, at least in the short term. The overall mortality rate is closer to 0.9% than 3.4% but age matters.
- The key strategies the Report claims can achieve suppression, actually ending new cases, is universal social distancing, quarantine cases and their households, close schools and universities.
Doing nothing in the US, an option totally rejected, would lead to an estimated 2.2 million deaths. Doing these three strategies for only 3 months would lead to 1.1 million deaths. Keeping these three strategies in place until a definitive therapy- medication or vaccine, could theoretically prevent any further death from this disease, but can we sustain such severe restrictions for over a year?
This is a dangerous pandemic, a real plague, we join all Americans, and all people of the world in doing all we can to reduce the number of us infected, taken ill, and of course dangerously ill.
To your health,
Dr. Arthur Lavin