A new report from the Institute for Disease Modeling shows the decrease in COVID-19 transmission in King County has slowed. Continued social distancing, and additional disease control measures, are necessary to avoid a rebound in new cases that could overwhelm the healthcare system.
Research shows COVID-19 transmission decline slowing, rapid rise in disease at risk without continued social distancing
A new report details how social distancing measures have reduced transmission of COVID-19 in King County to the point where new cases are expected to slowly decline or plateau at current levels. Additional interventions to further cut transmissions should be in place before social distancing measures could be relaxed to avoid risk to public health.
Modeling from the Institute for Disease Modeling (IDM) show the effective reproductive number – the number of new cases stemming from each COVID-19 infection – has declined from around 3 in early March to near 1 through April 4. This is consistent with previous estimates since the statewide Stay Home, Stay Healthy order went into effect on March 23.
We’ve done a very good job in King County suppressing transmission of COVID-19 and that’s largely due to the great work of our community in staying home and distancing to the extent possible," said Dr. Jeff Duchin, Health Officer for Public Health – Seattle & King County. "However, we still have way too many cases occurring each day. That means we’re vulnerable to a rebound that could potentially overwhelm our healthcare system if we prematurely ease up on our distancing steps."
Projecting forward, if distancing measures were lifted starting May 1, IDM’s new model predicts a rapid rise in the rate of cases that would likely exceed recent peak levels by the end of the month.
In contrast, if new strategies are added on top of current distancing measures -- such as a significant increases in testing for COVID-19, and detailed contact tracing of those who have contracted COVID-19—the model suggests the effective reproductive number would drop further and the number of cases would go down more quickly.
Until then, the report suggests, disease transmission will remain extremely sensitive to policy choices and community behavior.
I want to acknowledge how difficult this is for everyone in our community, socially, emotionally and economically," said Dr. Duchin. "We're doing everything we can to understand how we can allow a stepwise relaxing of our current physical distancing strategies without overwhelming our healthcare system. We are working hard to better understand how and where new infections are happening, which may suggest other measures that can help reduce transmission."
For more information about the report, read our blog post on Public Health Insider.
Daily totals for new COVID-19 cases and deaths are available on Public Health's Data Dashboard webpage, which updates as soon as data are available, typically between 1-3 p.m.
Isolation and quarantine facilities update
Isolation and quarantine is a proven public health practice for reducing the spread of disease. Examples of people who may need this assistance include people who cannot safely isolate from a family member who is elderly or medically fragile, or people experiencing homelessness. Individuals can only be placed into the King County sites after a health professional with Public Health has determined that they need isolation or quarantine.
Sixty people are currently staying in King County isolation, quarantine and recovery facilities. The number of residents at King County's isolation and quarantine sites is included in regular updates provided by Public Health. No other identifying or personal information will be provided.