Coronavirus testing got off to a disastrous start last year, putting the nation in a position of playing catch-up to the pandemic.
The delay in getting widespread testing in February, 2020, left local and state health departments blind to community transmission of the coronavirus. Now, a year removed from the first drive-thru testing sites, the crush of people seeking tests is gone, replaced by a rush to schedule vaccinations. But testing is an essential tool in the fight to suppress the coronavirus and to identify variants.
Diagnostic testing allows the public-health sector to understand the real-world effectiveness of the vaccines and whether people can be infected after inoculation and then spread the disease, said Dr. Charissa Fotinos, leader of Washington state's coronavirus testing.
"Even though it doesn't seem like it's important, it's very important to help us continue to understand how COVID-19 works and travels and how ultimately, we can do the best to protect ourselves," Fotinos said.
Since the public's attention turned to vaccines in December, the number of people seeking diagnostic testing has steadily fallen. Testing in Washington topped out on Nov. 23 with a seven-day rolling average of 33,404 tests. The largest one day total was on Dec. 21 with 44,427 tests.
Testing has flattened since the beginning of March. The most recent day of complete numbers from the state Department of Health showed 17,507 tests, with a rolling seven-day average of 10,254.
During the first month of the pandemic, most samples for testing had to be sent to the Centers for Disease Control and Prevention in Atlanta. The CDC eventually developed a flawed test it sent to labs across the country, further limiting testing.
The results of these early tests were used by public-health officials to identify and quarantine the sick and to connect with close contacts of the infected.
Testing expanded in March 2020 once non-CDC-developed tests were authorized. Health departments were quickly smothered by the volume of cases. The number of cases led public-health departments in King, Snohomish and Pierce counties to curtail contact-tracing efforts by mid-March 2020.
The need for continued access to testing was highlighted a couple of weeks ago when the city of Seattle decided to keep open its testing locations in Rainier Beach and West Seattle that had been set to switch to administering vaccines. The reversal was in reaction to an increasing number of confirmed cases of COVID-19 in the city.
An increasing case count made it clear that "robust, free testing" was needed throughout Seattle, Mayor Jenny Durkan said at the time."
Seattle isn't alone. Confirmed cases of COVID-19 are increasing across the state. DOH's latest situation report shows cases began increasing late last month after flattening in February, with the biggest jumps in the state's five largest counties, including King, Snohomish and Pierce.
At the seven testing sites run by Public Health — Seattle & King County, the number of tests administered has increased since February, as has the positivity rate, which is averaging between 8% to 13% at the county's sites, said Dr. Mark Del Beccaro, who leads Public Health's COVID-19 testing programs.
Last year, the World Health Organization urged governments to not emerge from stay-home orders until a community's positivity rate was below 5%.
Knowing where disease activity is high and knowing which variants are in the community are reasons why robust testing will be needed even as more people are vaccinated, Del Beccaro said.
"The concern is not only that rates are going up, but the number of variants that are being detected is also rising," he said. "So we're in this really difficult position right now racing to vaccinate."
An increase in the various variants worries public-health officials because each variant carries with it the possibility of being more transmissible, more deadly and better at avoiding antibodies, both natural and vaccine-induced.
The B.1.1.7, first identified in the United Kingdom; the B. 1.351, originally found in South Africa; and the P. 1 variant, which emerged in Brazil, are all circulating in Washington. Two other variants being closely watched by public-health officials are two that sprung from California, the B. 1.427 and B. 1.429 variants.
State testing has shown that as of March there were about 600 cases of the variants in Washington.
The introduction of the vaccines has understandably buoyed the mindset of people, which is good but also problematic because of the high level of transmission across the nation happening in the 80% of the population not yet vaccinated, said Dr. Jeffrey Townsend, a professor at the Yale School of Public Health.
"Unfortunately, the current epidemic state is not one we should be proud of. Right now, there is a very, very high level of transmission," Townsend said.
Washington's rising numbers mirror what Townsend is seeing across the country. The biggest increases in Washington are in people ages 10 to 49. People between these ages mostly haven't been made eligible for vaccination. That will be remedied Thursday, when everyone 16 and older will have the option of being vaccinated.