A nurse treating coronavirus patients at a care home in the US has shared a common symptom that all of the infected have shared so far.
Chelsey Earnest, who works at Life Care Center in Kirkland, Washington state, said all of the patients at the home had red eyes.
The centre has so far seen 129 patients and staff become sick, with 35 confirmed deaths.
Chelsey said redness around the eyes was the most important sign someone was infected with the virus.
She added that if she told a doctor somebody had red eyes, a hospital bed was made ready for them.
Speaking to CNN from the epicentre of Washington's outbreak, she said: "It's something that I witnessed in all of the patients.
"They have allergy eyes. The white part of the eye is not red. It's more like they have red eye shadow on the outside of their eyes."
So far, health authorities haven't listed red eyes or any eye complaints on lists of coronavirus symptoms.
The official symptoms include fever, cough, and shortness of breath.
Emergency signs are persistent pain or pressure in the chest and bluish lips.
But on Sunday, the American Academy of Ophthalmology sent an alert about reports that the virus can cause conjunctivitis, an inflammation of the membrane lining the eyelid.
Chelsey went on: "We've had patients that just had the red eyes as the only symptom that we saw and go to the hospital and pass away.
"I've even had the disaster medical control physician say: 'Do they have the red eyes?' And I will say: 'Yes'."
Life Care Center, just outside of Seattle, has been one of the hardest hit from the virus since the first cases were detected in the state of Washington last month.
As of Tuesday, at least 129 patients, staff and visitors had been infected, with 35 dying including 18 patients.
Jeffrey Duchin, an officer for Public Health, Seattle & King County, said he asked hospitals to offer staff but had been unsuccessful.
"I personally would have thought that we would have been able to muster more staff from our local healthcare system," he told KUOW.
"But I think everybody at this point was already experiencing some degree of COVID-19 stress and didn't feel like they had staff that they could spare."
It comes as the US has seen a huge surge in coronavirus cases in recent days, up to almost 55,000.
There have also been 783 deaths in the US, with a huge number of cases in New York state.
Despite this, President Donald Trump has declared that his country will be open as normal by Easter Sunday, just three weeks away, and declared he wouldn't instate a lockdown to prevent the disease spreading.