On March 23, Public Health — Seattle & King County and the team behind the Seattle Flu Study launched the greater Seattle Coronavirus Assessment Network—or SCAN for short. Thanks to the participation of volunteers across the county, SCAN has already begun to identify cases that might otherwise...
publichealthinsider.com
On March 23, Public Health — Seattle & King County and the team behind the Seattle Flu Study launched the
greater Seattle Coronavirus Assessment Network—or SCAN for short. Thanks to the participation of volunteers across the county, SCAN has already begun to identify cases that might otherwise have gone undetected.
In its first 18 days, SCAN tested 4,092 samples. Nearly two-thirds of those were returned by individuals who in the seven days prior to enrollment had reported COVID-like illness (fever, cough, or shortness of breath). However, more than three-quarters of these individuals indicated they had not yet sought medical care. SCAN is the first COVID-19 surveillance program in the U.S. to use “swab-and-send” test kits that allow individuals to collect their own nasal sample and return it to a lab for testing without leaving home—while observing physical distancing guidance and reducing exposure to others.
SCAN testing among those reporting COVID-like illness (CLI) returned 44 (1.6%) positive results for COVID-19—a proportion lower than that being returned through testing within the medical system, but one that may still represent thousands of unrecognized infections in the community.
Cases were identified in all parts of King County. Based on this participant and county census data, SCAN modeling estimates that community prevalence of COVID-19 for the period is between 5 and 75 out of 10,000 people (0.05% to 0.75%), with best estimate of 24 per 10,000 (0.24%).
This early sample shows that community prevalence is around 0.32% (and ranging from 0.08% to 1.18%) during the first six days of testing and 0.07% (and ranging from 0.01% to 0.36%) in the last six. Although the trend is decreasing, the team cautions that the conclusion is uncertain and not statistically significant given the sample size. We are also still learning about the population represented in SCAN and it is too early to draw general conclusions from the data.
www.latimes.com
