Sore and itchy eyes can be an early warning sign of Covid-19 infection, new findings show.
Researchers have found that eye problems can be an indication that someone is infected with the virus, and symptoms begin within two weeks before any other signs appear.
Symptoms to look for
Although high fever, new and persistent cough, and loss of taste and smell are the most common symptoms of Covid-19, recent research has shown that sore, itchy eyes are one of the most significant ocular symptoms in patients with coronavirus.
The study, published in the BMJ Open Ophthalmology, also indicated sensitivity to light – known as photophobia – as another sign of a viral infection.
Researchers from the University of Anglia Ruskin studied the data of 83 patients with Covid-19 and found that the following symptoms were the most reported:
- Dry cough – 66 percent
- Fever and fever – 76 percent
- Fatigue – 90 percent
- Loss of taste and smell – 70 percent
However, when assessing eye-related symptoms, the team found that 18 percent suffered from photophobia, 17 percent had itchy eyes, and 16 percent reported having sore eyes.
When do eye symptoms occur?
The study found that the incidence of sore eyes was significantly higher when a person experienced the three main symptoms of coronavirus, than before.
But as many as 81 percent reported having eye symptoms within two weeks of the onset of other Covid-19 symptoms.
Four out of five patients said that their eye problems lasted less than two weeks in total and that no differences were found between men and women.
Previous studies have suggested that Covid-19 can cause eye infections, such as conjunctivitis, although the World Health Organization (WHO) cites it as one of the rarer signs.
Meanwhile, Italian researchers discovered early in the pandemic that Covid-19 could remain in a person’s eyes for up to 21 days after they first develop symptoms.
Scientists from the National Institute of Infectious Diseases discovered that a 65-year-old woman had red, infected eyes before the classic signs of coronavirus showed and that she remained in her eyes for exactly three weeks.
Researchers examined her five days after she was discharged from the hospital and found that the virus had returned to her eye fluid, and she still remained even after the swabs from her nose cleared the virus.
This suggested to the researchers that the virus continues to make copies in its eye fluid, which leads to the warning that conjunctivitis could be an early sign of coronavirus.
Conjunctivitis is “too wide”
The team in Cambridge, led by Professor Shahina Pardhan, director of the vision and eye research unit at Anglia Ruskin University School of Medicine, has since further studied eye symptoms and found that sore eyes are the most significant symptom, not conjunctivitis.
Professor Parhhan explained: “The most significant eye symptom experienced by people suffering from Covid-19 was sore eyes.
“Other symptoms associated with other types of conjunctivitis, such as mucous discharge and sharp eyes associated with a bacterial infection, have not reached significance.
“The term ‘conjunctivitis’ is too broad and should be used with caution.”
The College of Optometrists and the Royal College of Ophthalmologists added that it is unlikely that patients will develop red eyes without other symptoms of coronavirus.
A spokeswoman said: “Recent reports suggest that Covid-19 can cause conjunctivitis, and it is known that virus particles can be found in tears, which has caused some concern among eye health workers.
“It has been recognized that any upper respiratory tract infection can result in viral conjunctivitis as a secondary complication, and this is also the case with Covid-19.
“However, it is unlikely that a person would develop viral conjunctivitis secondary to Covid-19 without other symptoms of fever or persistent cough, as conjunctivitis appears to be a late feature where it has occurred.”