Coronavirus has radically altered life in the United States at mind-bending speed in the past three months and our understanding of the virus is changing just as quickly.

More than 2.5 million cases have been confirmed worldwide, and the U.S. has reported more than any other nation. A large portion of the country now lives under stay-at-home orders, plaguing the economy and causing millions of Americans to lose their jobs.

At the same time, public health officials are often adjusting policies as new research reveals more about the virus and its symptoms. It's happening at a pace that can be bewildering and confusing to the average person.

To help you keep up with all the changes, here’s a running list of what we know about the new coronavirus and the illness it causes, COVID-19:

Reports of new coronavirus symptoms: loss of taste or smell, 'COVID toes'

When the World Health Organization and the CDC first warned about the new coronavirus, they urged the public to be on the lookout for these three main symptoms: fever, dry cough and difficulty breathing.

There were some reports of gastrointestinal issues, such as diarrhea, but these symptoms appear to be rare.

Since then, doctors have been able to identify more symptoms in patients.

There are now six new symptoms that the CDC cautions could be signs of the coronavirus: chills, repeated shaking with chills, muscle pain, headache, sore throat and a loss of taste or smell.

Shortness of breath was tweaked to "shortness of breath or difficulty breathing" by the CDC. The CDC recommends seeking "medical attention immediately" for trouble breathing, persistent pain or pressure on chest, bluish lips or face, or a new confusion or inability to awaken.

The medical term for loss of smell is anosmia,while the term for an altered sense of taste is dysgeusia.

South Korea, China and Italy have all reported "significant numbers" of known COVID-19 patients with lost or reduced sense of smell, according to a joint statement by Claire Hopkins, president of the British Rhinological Society, and Nirmal Kumar, president of ENT UK.

"In Germany it is reported that more than 2 in 3 confirmed cases have anosmia. In South Korea, where testing has been more widespread, 30% of patients testing positive have had anosmia as their major presenting symptom in otherwise mild cases," they wrote.

Another more recent symptom accumulating more anecdotal evidence has been informally called “COVID toes.” It’s the presence of purple or blue lesions on a patient’s feet and toes, most commonly appearing in young adults.

While experts can’t pinpoint the condition, some have hypothesized that it could be excess inflammation or a micro-clotting of blood vessels.

US coronavirus deaths: First one took place 3 weeks earlier than previously reported

President Donald Trump announced the first coronavirus fatality Feb. 29, but California officials later announced coronavirus fatalities that occurred weeks earlier.

The medical examiner in Santa Clara County, southeast of San Francisco, said April 21 that autopsies on the bodies of two people who died Feb. 6 and Feb. 17 showed that they were positive for the virus.

The victims "died at home during a time when very limited testing was available only through the CDC," Dr. Michelle Jorden said in a statement. She said criteria set by the CDC at the time restricted testing only to individuals with a known travel history and who sought medical care for specific symptoms.

Should I wear face mask for coronavirus? CDC said no, then yes.

For months, the Centers for Disease Control and Prevention urged the mass public not to wear a mask unless they were sick or caring for a COVID-19 patient, citing concerns about supply and effectiveness.

They reversed that guidance in early April.

Now, the CDC recommends people wear homemade or cloth masks in public. The agency says the mask should fit snugly against the face, be secured with ties or ear loops, include multiple layers of fabric and be laundered after every use.

The new guidance came after research suggested that presymptomatic and asymptomatic carriers were able to transmit the virus and infect healthy people.

Officials recommend wearing these masks in public settings where social distancing measures are difficult to maintain, such as grocery stores and pharmacies. Many cities and states require masks in public, including New York, New Jersey and Los Angeles.

Is the coronavirus deadlier than the flu?

Before the coronavirus was declared a pandemic, experts noted that coronavirus cases were incomparable to this season’s influenza impact.

"Everybody is being cautious because we’re still learning about it, but right now you’re sitting in the midst of an influenza seasonal busy-ness," said Dr. David Hooper, chief of the Infection Control Unit at Massachusetts General Hospital, in late January.

"The risk is much higher for influenza for people in the U.S. than this new coronavirus."

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However, that quickly changed as COVID-19 spread rapidly and fatality rates surpassed those seen typically seen in the seasonal flu.

In a March 3 teleconference, WHO Director-General Tedros Adhanom Ghebreyesus said that globally, the seasonal flu kills far less than 1% of those infected while about 3.4% of reported COVID-19 cases have died.

Even that fatality rate is uncertain and varies between countries, although most nations report a death rate significantly higher than the flu. In the U.S., limited testing has made it difficult to determine an accurate number.

Contributing: John Bacon, Ryan Miller and Susan Miller, USA TODAY. Follow Adrianna Rodriguez on Twitter: @AdriannaUSAT.