Sore eyes common vision-based indicator of COVID-19, study finds

Sore eyes are the most significant vision-based indicator of COVID-19, according to a study led by an Indian-origin scientist which provides more understanding of how the novel coronavirus travels through the body.

Researchers at Anglia Ruskin University (ARU) in the UK asked people who had a confirmed COVID-19 diagnosis to complete a questionnaire about their symptoms, and how those compared to before they tested positive.

"This is the first study to investigate the various eye symptoms indicative of conjunctivitis in relation to COVID-19, their time frame in relation to other well-known COVID-19 symptoms and their duration," said study lead author Professor Shahina Pardhan, Director of the Vision and Eye Research Institute at ARU.

The study, published in the journal BMJ Open Ophthalmology, found that sore eyes was significantly more common when the participants had COVID-19, with 16 per cent reporting the issue as one of their symptoms.

Just 5 per cent of the participants reported having had the condition beforehand, the researchers said.

While 18 per cent of people reported suffering from photophobia or light sensitivity as one of their symptoms, this was only a 5 per cent increase from their pre-COVID-19 state, they said.

The study found that of the 83 respondents, 81 per cent reported ocular issues within two weeks of other COVID-19 symptoms, and of those, 80 per cent reported their eye problems lasted less than two weeks.

The most common reported symptoms overall were fatigue -- suffered by 90 per cent of respondents -- a fever seen 76 per cent and a dry cough which was reported by 66 per cent.

"While it is important that ocular symptoms are included in the list of possible COVID-19 symptoms, we argue that sore eyes should replace 'conjunctivitis' as it is important to differentiate from symptoms of other types of infections, such as bacterial infections, which manifest as mucous discharge or gritty eyes, Pardhan said.

"This study is important because it helps us understand more about how COVID-19 can infect the conjunctiva and how this then allows the virus to spread through the body," she added.