As the COVID-19 pandemic is rapidly progressing, most countries have implemented physical distancing measures community-wide. As transmission dynamics begin to decline, along with incidence of COVID-19 cases, there will be a need for decisions at the country level about how to transition out of strict physical distancing and into a phased reopening.
Models have shown that, in the absence of social distancing, COVID-19 has a Reproduction rate (Ro) of between 2 and 3, this means, on average every person with the disease will spread it to 2 to 3 others [1]. To end an epidemic, control measures have to be in place to drive that number as far below 1 as possible. Meanwhile, social distancing measures, combined with case-based interventions, are the key tools to maintaining the Ro below 1 [2]. If the Ro rises above 1, this means the curve has been heightened. If that occurs, it may be necessary to re-initiate large-scale physical distancing. It is important to recognize that countries will need to actively manage COVID-19 cases with surveillance for the entire duration of the pandemic until a safe and effective vaccine is widely available.
As we transition out to phase II, economies can begin a process of reopening, with modifications. Rather than asking everyone to stay home, countries can limit SARS-CoV-2 transmission through a combination of physical distancing and case-based interventions (testing, contact tracing, and self-isolation for those with active disease or individuals who may have contracted SARS-CoV-2 and are awaiting test results), which in most places may require an expanded workforce and resources.
This document is limited to phases of reopening and does not address other important matters related to the risk of SARS-CoV-2 transmission in businesses, schools, etc. which are considered nonessential by countries.
This table summarizes 4 phases and identified capacities required in each phase, as well as the triggers needed to progress from one phase to the next [3].
Based on the public health principles [7], coming days will have the following in place until we have a therapeutic option or an effective vaccine:
Phases |
Goals |
Thresholds for action |
Triggers for transitioning to next phase |
Steps required |
Phase I
Slow the Spread |
1) To ask community-level physical distancing measures to “slow the spread.”[4]
2) To increase access to diagnostic testing and increase public health and medical system capacities. |
To slow the spread in this period, schools are closed across the country,
workers are being asked to do their jobs from home
when possible, community gathering spaces such as
malls and gyms are closed, and restaurants are being asked to limit their services. These measures will need to be in place in each state until transmission has measurably slowed down and health infrastructure can be scaled up to safely manage the outbreak and care for the sick.
These capacities are needed to safely identify and treat all COVID-19 patients and to prepare for a shift from community mitigation (what we are doing now) to case-based interventions (when we try to control spread by focusing testing and resources on individuals with disease who may be infectious and their close contacts). |
When following 4 criteria have been met [5]
(1) the number of new cases has declined for at least 14 days;
(2) rapid diagnostic testing capacity is sufficient to test, at minimum, all people with COVID-19 symptoms, as well as close contacts and those in essential roles;
(3) the healthcare system is able to safely care for all patients, including having appropriate personal protective equipment for healthcare workers; and (4) there is sufficient public health capacity to conduct contact tracing for all new cases and their close contacts. |
These capacities are needed to safely identify and treat all COVID-19 patients and to prepare for a shift from community mitigation (what we are doing now) to case-based interventions (when we try to control spread by focusing testing and resources on individuals with disease who may be infectious and their close contacts).
Issuing stay-at-home advisories in hot spots
where transmission is particularly intense
(i.e., when case counts are doubling in a city or
locality every three to five days); and |
Phase II
Reopen, State by State |
1) Lift strict physical distancing measures in a
concerted and careful fashion,
2) Allow the vast majority of businesses and schools to open, and
3) Continue to control SARS-CoV-2 transmission
so we do not revert back to Phase I. |
Businesses and sectors can begin a process of reopening, with modifications.
For older adults
(those over age 60), those with underlying health
conditions, and other populations at heightened
risk from COVID-19, continuing to limit time in the community will be important. |
Physical distancing
restrictions and other Phase II measures can be lifted when safe and effective tools for mitigating the risk of
COVID-19 are available, including broad surveillance, therapeutics that can rescue patients with significant disease or prevent serious illness in those most at risk, or a safe and effective vaccine. |
The public will initially be asked to limit gatherings, and people will initially be asked to wear fabric nonmedical face masks while in the community to reduce their risk of asymptomatic spread [6].
Testing should become more widespread and routine as point-of-care diagnostics are fully deployed in doctors’ offices.
Rather than asking everyone to stay home, states can limit SARS-CoV-2 transmission through a combination of physical distancing and case-based interventions (testing, contact tracing, and self-isolation for those with active disease or individuals who may have contracted SARS-CoV-2 and are awaiting test results), which in most places may require an expanded workforce and resources. |
Phase III
Establish Protection
Then Lift All Restrictions |
1) Prevent infection;
2) Treat those with early disease to prevent bad
outcomes;
3) Provide a prophylaxis for those exposed to infection to prevent them from developing disease or reduce its severity;
4) In the case of a vaccine, build population-level
immunity to the virus in order to reduce illness
and death and stop or greatly slow spread; and
5) Enable the lifting of all physical distancing
measures. |
The new prioritization guidance for the COVID-19 vaccine should identify priority groups for targeted distribution when a safe and effective vaccine starts to become available.
Mass Vaccination or Therapeutic Distribution— When Supply Is Abundant.
Global Vaccine Scale-Up and Vaccination. |
Looks ahead to a time when an effective therapeutic or vaccine is available.
Serological Surveys to Determine Population
Immunity: If a sufficiently high fraction of the population
has become immune either through natural recovery
or vaccination, remaining restrictions can be lifted |
While we need to better understand the strength of the immune response in mild cases and how long people remain immune from reinfection, we know there is a period where most people will have sufficient antibodies to offer protection. |
Phase IV
Rebuild Our Readiness
for the Next Pandemic |
Identifies some policy priorities for increasing preparedness for the next public health threat |
- Develop Vaccines for Novel Viruses in Months, Not Years;
- Modernize and Fortify the Health Care System;
- Establish a National Infectious Disease Forecasting Center; and
- Governance
|
|
Will require investment into research and development initiatives, expansion of public-health and health care infrastructure and workforce, and clear governance structures to execute strong preparedness plans.
Properly implemented, the steps described here also
provide the foundation for containing the damage
that future pathogens may cause. |
1. Physical Distancing- wherever possible people will work or access the business from home; needs restructuring responsibilities to minimize the number of workers that need to be physically present.
2. Engineering controls- creating physical barriers between people (ideally, at least 6 feet).
3. Administrative controls0- redistributing responsibilities to reduce contact between individuals, using technology to facilitate communication.
4. PPE- Wearing non medical cloth masks.
This document briefly summarizes the phases of reopening. Decisions should be made carefully and thoughtfully to limit the risk of second wave of the disease [8].