In fact, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, reported Friday that to stop the pandemic in its tracks, Americans will have to stay home for “at least several weeks.”
While the advice may not sit well with the president, his words are backed up by a new social-distancing study that demonstrates exactly why 'reopening' America is a bad idea for our health.
On Tuesday March 24, President Donald Trump said he would “love to have the country opened up and just raring to go” by April 12, which is Easter Sunday.
He says that “we need to go back to work, much sooner than people thought.”
The study utilizes an influenza epidemic simulation model, which estimated the likelihood of human-to-human transmission of SARS-CoV-2, the virus that causes the disease COVID-19, dependent on what steps are taken to prevent it from spreading.
The model showed that the most effective way of reducing cases is by taking a combined intervention approach — an amalgamation of physical distancing interventions, closing schools, workplace distancing, and quarantining people infected, along with their family members.
The case for combined intervention
Ultimately, all the separate intervention scenarios were significantly more effective at reducing cases than no intervention at all. In order, the most-to-least effective strategies were:
1. The combined approach.
2. Quarantine plus workplace measures (defined as 50 percent of workers working from home for two weeks).
3. Quarantine plus school closure.
4. Quarantine alone.
Importantly, the most-effective measures all rely on some form of social distancing.
The results are based on a faux Singaporean population, simulated through an influenza epidemic modeling program called FluTE. The synthetic population was generated using 2010 census data from Singapore, which includes demographic characteristics, like family size and employment.
In terms of the simulated influenza epidemic, these were the conditions the researchers set: Virus incubation period was set at 5.3 days, the duration of time at the hospital after symptom onset at 3.5 days, and it was assumed that 7.5 percent of the population was asymptomatic.
The study authors note that since the novel coronavirus outbreak began in Wuhan, 68 “imported cases” and 175 locally acquired infections have been reported in Singapore. This study is part of an effort to determine what steps should be taken in Singapore now to contain the virus.
This model suggests that the combined approach could, the team finds, “prevent a national outbreak at low levels of infectivity and reduce the number of total infections considerably at higher levels of infectivity.”
The team randomly placed 100 cases of COVID-19 among the population and ran the simulations for an 80 day period.
For the purposes of the simulation, they also assumed that no individuals had existing immunity to the virus, and used SARS-COV parameters to estimate the infection rate of SARS-CoV-2. Different models either incorporated no intervention or the four intervention scenarios.
Importantly, “quarantine plus immediate workplace distancing” was defined as 50 percent of the workforce being encouraged to work from home for two weeks.
The results indicated that a combined approach could stop a national outbreak when there were low levels of infectivity — higher infectivity scenarios were harder to contain, even when all intervention steps were taken. The researchers explain that this is because, while certain steps can reduce the number of total infections, at that level, transmissions can still happen.
Specifically, the combined intervention method — when enacted at the very start of the outbreak — was effective at reducing the median number of infections by 99.3 percent. In Singapore, that would mean preventing 1,800 cases.
The study results get really interesting when the level of outbreak severity changed.
If the outbreak was dialed up to moderate, the estimated caseload jumped to 50,000 cases. At the “high” level of outbreak, meaning transmissibility is very possible, cases rose to 258,000, despite the implementation of the combined intervention method.
If more asymptomatic cases are assumed, then the number of infected people grew across the board.
Study co-author Alex Cook, associate professor at the National University of Singapore, explained in a statement accompanying the research that higher asymptomatic rates mean that “public education and case management become increasingly important.”
“If the preventative effect of these interventions reduces considerably due to higher asymptomatic proportions, more pressure will be placed on the quarantining and treatment of infected individuals, which could become infeasible when the number of infected individuals exceeds the capacity of health-care facilities,” Cook says.
The model has its limitations — what we know about COVID-19 is still preliminary, and the models can’t account for unforeseen factors, like where exactly people will go, who they will spend their time with, and how vulnerable each individual is to the virus.
But the results do underscore one thing: Social distancing of some kind does seem to work, especially if done quickly and across social, work, and school environments.
In a related commentary, the study authors note that while a mathematical model is the only “viable and timely method” we currently have to gather evidence like this, each intervention approach does involve “considerable societal disruption.”
Closing schools, and leaving work fundamentally changes lives — and not everyone is equipped, whether it be socioeconomically, emotionally, or even physically — to handle these changes in a sustainable way.
It is also important to note that, unlike the model used here, the number of COVID-19 cases in the United States has moved far beyond the baseline.
How many, exactly, depends on what actions the country takes, and what advice we decide to listen to.
Interpretation: Implementing the combined intervention of quarantining infected individuals and their family members, workplace distancing, and school closure once community transmission has been detected could substantially reduce the number of SARS-CoV-2 infections. We therefore recommend immediate deployment of this strategy if local secondary transmission is confirmed within Singapore. However, quarantine and workplace distancing should be prioritized over school closure because at this early stage, symptomatic children have higher withdrawal rates from school than do symptomatic adults from work. At higher asymptomatic proportions, intervention effectiveness might be substantially reduced requiring the need for effective case management and treatments, and preventive measures such as vaccines.