Months into the coronavirus pandemic, the US is finally consistently reporting 500,000 Covid-19 tests a day. That’s the bare minimum of daily new tests that some experts have long said is needed to properly track and contain the nation’s coronavirus outbreak.
The US reported more than 500,000 tests a day every day over the weekend of June 19, according to the Covid Tracking Project. The nation previously hit the standard the previous weekend, but over the ensuing week fell back below 500,000 tests a day.
The figures are a significant improvement from previous months. For much of May, the US reported less than 400,000 tests a day. In April, less than 200,000. In March, reported new tests began in the low hundreds.
Testing is a crucial component to getting control over the pandemic. When paired with contact tracing, testing lets officials track the scale of the Covid-19 outbreak, isolate the sick, quarantine those whom the sick came into contact with, and deploy community-wide efforts as necessary. The combination of testing and tracing is how other countries, such as South Korea and Germany, managed to control their outbreaks.
Since the coronavirus reached the US, experts have consistently called for a minimum of 500,000 tests a day — though some have gone further, calling for tens of millions of tests a day. The country initially struggled to scale up testing due to supply constraints for tests and materials required to run tests, as well as a lack of federal coordination. Over time, state and local governments and private actors have addressed these issues, albeit largely on their own.
In hitting 500,000 new tests a day, the US now has a crucial foundation for tracking and containing the coronavirus pandemic — right as cases appear to surge across much of the country. (More testing could explain at least part of the increase in new cases, since more testing means more detected cases.)
At least in theory, the greater testing capacity, if paired with contact tracing, should make it easier to respond to the current crisis.
Many states aren’t meeting this testing standard
The milestone comes with an important caveat: Not all states are equal when it comes to Covid-19 testing. As of June 22, just 20 states have hit 150 daily new tests per 100,000 people — the equivalent to 500,000 tests a day nationwide. (Washington and Wyoming are excluded due to recent errors and changes in test data reporting that make it hard to properly evaluate their current trends.)
By another metric, some states are doing better.
The positive rate, or positivity rate, gauges how many tests come back positive. An area with adequate testing should be testing lots and lots of people, many of whom don’t have the disease or don’t show severe symptoms. The positive testing rate in South Korea, for example, is below 2 percent. High positive rates indicate that only people with obvious symptoms are getting tested, so there’s not quite enough testing to match the scope of an outbreak.
Generally, the positive rate should be no higher than 5 percent. As of June 22, 29 states meet this standard. (Again, Washington and Wyoming are excluded.)
Still, some states, especially in the South and West, are doing poorly — with Arizona in particular reporting a positive rate above 20 percent. That’s a sign not just of insufficient testing but also significant Covid-19 outbreaks in these states.
The state-by-state differences in testing are concerning for addressing the current wave of Covid-19 cases. Coronavirus outbreaks in the US are regional — meaning different states, counties, cities, and even hospitals are getting hit at different levels. New York Times data shows 23 states — mostly in the South and West — have seen recent increases in Covid-19 cases, while the rest have remained flat or seen recent drops.
Based on these numbers, experts say that it’s important not just that the nation as a whole hit certain thresholds for coronavirus test capacity, but that each state, county, and city does to meet localized challenges.
To that end, the US as a whole may now hit the minimum for coronavirus testing experts recommend. But most states have not met that minimum — and that puts them at greater risk as the country again starts to see a spike in Covid-19 cases.
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