COVID-19 Testing: Why It Matters to Re-Opening the Economy, What it Takes, and Where Things Stand

All we want right now is a return to some semblance of normalcy. We want to see our loved ones, go to work, and send our kids to school. But even more than that, we want to know that we and our loved ones are safe.

We don’t have to look very far to see what unsafe looks like. The national news has countless stories mass illness and death, of overloaded hospitals, and people unable to get the help that they need.

Thanks to the Governor’s Safer at Home order, we’ve avoided this. Dane County’s progress stands out even more: while the nation sees the number of COVID cases doubling every 18 days, in Dane County, it takes about 30 days for the number of cases to double. That means you’ve been listening and taking the Safer at Home order seriously.

We’ve been careful, and it shows in our outcomes. While we want to open our economy back up, we need to be just as careful in doing so to avoid backsliding. The last thing we want is to repeat this last month again. We avoid that by reopening one step at a time, and always following the data. One of the most critical types of data is how many people have been tested, and how many positive tests we see in our community.

Back in March, we had a low supply of COVID-19 test kits, so, anybody with symptoms had to be treated as potentially COVID-positive, and we didn’t always have capacity to learn who else they might have interacted with. In that scenario, we had to plan for the worst, and close down all possible sources of COVID exposure. In order to be confident about easing back these restrictions, we need much more testing capacity.

Increasing testing capacity has not been a simple endeavor. With the entire world looking for COVID-19 testing kits at the same time, there have been global supply chain shortages of key test kit components and ingredients, including shortages in the nasopharyngeal (NP) swabs used to take samples, shortages in the particular saline solution used as a transport medium, and shortages of a key test ingredients called reagents. Solutions to these shortages are in the works globally and locally. Some testing facilities are turning to alternative swabs for taking samples, while other companies shifted to manufacturing more NP swabs. Increasing supply of the right transport medium is easier – the CDC posted a recipe for it on their website that local labs can use to make it themselves.

We have also been fortunate to have great local partners helping us to fill these gaps. Promega, based in Fitchburg, is manufacturing reagents and testing kits. Here in Madison, Exact Sciences has stepped up to conduct COVID tests and can run 20,000 tests per week under a contract with the State. The State has now set up a website where local labs in Wisconsin can submit requests for individual components or full test kits if they are facing shortages, and the State will work to distribute that supply.

The Governor’s Badger Bounce Back Plan outlines a need to test 12,000 people per day in Wisconsin. We’re getting closer to that number, with the capacity for about 11,000 tests per day. Testing capacity is expanding all over the state – in major labs like the State Lab of Hygiene and the Milwaukee Public Health Lab, and with over 70 local healthcare providers. But we still need more. Exact Sciences wants to do this testing and has rapidly developed a sophisticated genetic test to aid the state of Wisconsin. Rep. Mark Pocan notes that at full capacity, it could run 120,000 tests a week. I agree with Pocan that “It’s time to take full advantage of that ingenuity,” and that the barriers to testing need to be solved as rapidly as possible.

We’re also increasing the number of people with mild COVID-like symptoms that can be tested. One month ago, the shortage of tests meant that the bar for receiving a test was high: it was only available to people whose symptoms required hospitalization, and to symptomatic people where testing was important for controlling the spread -- people like first responders, women going into labor or people with symptoms in a congregant living facility like a nursing home or a jail. In the last couple of weeks, that has changed. Now, people with milder COVID-19 symptoms can be tested – and we want to test them! The more we know about who has this virus, the better we can limit their exposure to others.

Even with this desire for more complete information, we are still not testing people who have no symptoms of COVID-19. A COVID-19 test is a snapshot of one moment in time. Truly monitoring asymptomatic people via a COVID-19 test would require regular and repeated testing of everybody, which means these particular tests aren’t a very good tool for ongoing monitoring.

Another effort is underway to expand and improve antibody testing. If you have the antibodies to COVID-19, it means your body was already infected, fought it off, and developed the antibodies to quickly recognize it and fight it again in the future.

Antibody testing could give us a better understanding of the total number of COVID-positive cases and help provide better data on the true percentage of cases that turn severe. But that information would not necessarily allow us to re-open the economy faster because we don’t yet know if getting COVID once means you cannot get it again. Moreover, the antibody tests themselves are not yet as accurate as we need them to be. Fifteen percent of tests return false positives, meaning somebody would believe they’d already been exposed to COVID-19 when then had not been. This market may still develop and improve, but for now, we are keeping our focus on testing people with COVID-like symptoms

The closer we get to testing everybody with symptoms, the more we can carefully monitor the numbers, quickly isolate individual cases and ensure they get the healthcare they need, and quickly isolate others who were exposed. This approach gives us a much, much higher likelihood of avoiding a resurgence and keeping our curve on a downward trend. Of course, as we test more, we’ll surely identify more cases. It’s important to know this doesn’t necessarily mean we’ve had a spike in the true number of cases. Rather, it’s a spike in the number of confirmed cases.

If you’d like to follow the data on testing and our progress yourself, visit the State Badger Bounce Back website. You can see Dane County specific numbers here, and follow Public Health Madison & Dane County on Twitter and Facebook for more good information. In a future blog, we’ll discuss what happens after testing, and the other tools that are important in our fight against this pandemic.