The US just hit 1 million cases of coronavirus

People wearing masks and keeping their distance from one another while waiting in line outside Costco in Wheaton, Maryland.
People wearing masks and keeping their distance from one another while waiting in line outside Costco in Wheaton, Maryland. There are now more than 1 million cases of the coronavirus in the U.S. (Image credit: Nicole Glass Photography/Shutterstock)

The United States has reported 1 million cases of COVID-19 nationwide, as of today (April 28). That's about one-third of all reported cases of the disease in the world. 

Since the beginning of the coronavirus pandemic, case numbers and related data have been voluntarily collated by a few nongovernmental organizations, rather than by a central government agency like the Centers for Disease Control and Prevention (CDC). The groups are reliably collecting data from state health departments and local news reports, but occasionally their total counts may differ. 

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The COVID-19 Dashboard created by the Center for Systems Science and Engineering at Johns Hopkins University is reporting 1,002,498 cases of the coronavirus in the U.S. as of the afternoon of April 28, and 3,083,467 cases globally. The Worldometer is a database operated by statisticians and volunteers who work for Dadax, an independent company based in the U.S., and is reporting 1,022,259 cases of the coronavirus in the U.S., and 3,106,700 cases globally. 

Both databases use similar sources for their data, according to their websites, but Johns Hopkins dashboard reports data for 185 countries and regions, while Worldometer reports data for 212 countries and regions. 

No matter which database you follow, there are likely many more cases of the coronavirus in the U.S. than what's being reported, because testing has never been widely available. To make up for the presumed underreporting of numbers, New York City's report includes probable deaths and probable cases in the total count. Similarly, Maryland reports the number of probable deaths and Wyoming reports the number of probable cases. 

Although the total number of cases continues to increase, the number reported each day seems to be leveling off and becoming more consistent, according to several databases. (That's not to say that number isn't still high, though.) 

According to the Johns Hopkins COVID-19 Dashboard, between 25,100 and 36,200 cases have been reported each day in the month of April so far — a difference of around 11,000 cases between the highest and lowest days. That's much more stable than in March, when the number of cases skyrocketed from fewer than 1,000 total to more than 26,000 in just two weeks. The Worldometer is reporting a comparable trend. 

One issue with interpreting case numbers, however, is that the U.S. has conducted vastly more tests in recent weeks. For instance, it conducted about 25 times more tests on April 15 as it did on March 15, The Atlantic reported. That means that if you're sampling the same population, you would expect to find more cases now than we would have weeks ago, even if the percentage of the population that is infected had not changed. 

The number of COVID-19 deaths reported daily in the U.S. is still relatively variable, but since reaching a record of 2,683 COVID-19 deaths on April 21, no day has reached that number so far, according to the Worldometer. Since then, the number of deaths each day has held between 1,157 and 2,358. 

According to a model produced by the Institute for Health Metrics and Evaluation at the University of Washington, the U.S. may have already seen its highest number of COVID-19 deaths in one day on April 15, with 2,698 deaths (the Worldometer recorded 2,631 deaths on that date). Since then, the numbers have been lower. But as some states begin to allow businesses to reopen this week, time will tell how long the trends will hold. 

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Originally published on Live Science.

Kimberly Hickok
Live Science Contributor

Kimberly has a bachelor's degree in marine biology from Texas A&M University, a master's degree in biology from Southeastern Louisiana University and a graduate certificate in science communication from the University of California, Santa Cruz. She is a former reference editor for Live Science and Her work has appeared in Inside Science, News from Science, the San Jose Mercury and others. Her favorite stories include those about animals and obscurities. A Texas native, Kim now lives in a California redwood forest.