As the clock reached 1 p.m. today, I started my new daily ritual: visiting the Utah Coronavirus Task Force website to see the updates in the number of coronavirus cases and tests in the state. While day-to-day trends can be deceptive, the results for the past few weeks have been consistent.
Utah has, so far, avoided an overwhelming surge of cases of the coronavirus. Undoubtedly, this has saved lives, as fewer people have been infected and those who have become infected are able to receive lifesaving medical care.
One admirable aspect of Utah’s fight against the coronavirus is the push for more testing. The Test Utah initiative has led more people to get tested than before, and the number of people being tested each day in April dwarfs the March numbers. This has led to more people being diagnosed and quarantined, thereby slowing the spread of the virus. Impressively, the positive test rate has hovered at approximately 5%, despite the increase in testing.
Despite Utah’s admirable efforts to expand testing, on most days Utah could test twice as many people for the coronavirus than it does each day. With the potential to test many more people, the time has come to start testing representative samples of people who do not display symptoms.
Austria recently had such a program that tested 1,544 people in two days. The result indicated that there were approximately three times more active infections with no symptoms than confirmed symptomatic cases of coronavirus. An article published in Science suggested that in China, six times more people were infected during the course of the pandemic than had an official diagnosis.
One of the things that makes the coronavirus so virulent is its ability to spread when people do not display symptoms. Having a better understanding of the frequency of asymptomatic infections is critical for epidemiologists to estimate how quickly the virus has spread in a community and how many people have likely already been infected unwittingly.
This information is essential to determining when the peak of the pandemic has passed in a geographic area. That information can help leaders better plan for a timeline of lifting restrictions on businesses, movements and meetings — which may speed up economic recovery from the pandemic.
For Utah specifically, the question of hidden infections is critical. Utah is the youngest state in the country, and young people may be more likely to be infected without symptoms and pass on the coronavirus. A testing program of Utahns without symptoms would help experts understand whether the state has a hidden reservoir of carriers who might pass the coronavirus to more vulnerable individuals.
Austria’s experience shows that a representative sample could be tested in a few days. With some preliminary planning and cooperation from citizens who feel healthy, Utah could have an estimate of the number of infected people statewide very soon. A more ambitious testing program than Austria’s would also provide accurate information about the infection rate for subgroups — Hispanics, senior citizens, individuals in poverty, children, people in different parts of the state. If the program were long term, then a rolling testing program across weeks could reveal whether asymptomatic infections are increasing or decreasing.
Utah has been a leader in its coronavirus response since the beginning. Gov. Herbert’s early request for limits on meetings and the state’s high rate of voluntary compliance are paying off. Both Utah’s confirmed case rate and the growth of new confirmed cases remain lower than the rest of the country’s. Adding a testing program of people without symptoms would maintain Utah’s place as a leader in the coronavirus response, make good use of the state’s testing capacity, and provide essential information to scientists and leaders.
Russell Warne is a scientist living in Provo. Twitter: @Russwarne.