Introduction
COVID-19. Coronavirus. It is the global pandemic that is affecting everyone around the world in some form or another. As the precautions and health advice regarding COVID-19 continues to evolve, there is also specific information and knowledge to share about what you need to know about COVID-19 and your eyes.
What is COVID-19?
COVID-19 is a newly evolved virus that is part of the coronavirus family. For those people who contract the COVID-19 virus it causes respiratory illness that is mostly mild to moderate, though it can also be very serious and even fatal in some.
COVID-19 spreads by droplet transmission, which is when you come into contact with droplets containing the virus. The most common ways this occurs are directly from the cough or sneeze of someone infected with coronavirus, or indirectly by touching objects or surfaces that contain droplets from an infected person and then touching your mouth or face. This is why all major global health organisations and governments have advised everyone to frequently wash our hands and avoid touching our eyes, nose and mouth as these are common sites for the virus to enter our bodies.
Can COVID-19 spread through via the eyes?
Our eyes have a tear film which coats the front of the eyeball. The tear film consists of water and mucous layers to help keep our eyes moist. It is known that other common viruses (influenza, adenovirus) can spread into the tear film and cause illness or conditions involving the eye and/or the whole body. As COVID-19 is also a virus, it is believed that this new coronavirus can spread through the eyes in a similar way. However a recent breaking study in Singapore did not find any trace of COVID-19 in the tears of people infected with coronavirus. This suggests the risk of virus transmission through our tears is low. Though this is potentially good news, it is better to be safe than sorry so please continue to wash your hands and avoid touching your eyes, nose or mouth.
Can COVID-19 affect my eyes?
What we do have more evidence for is how COVID-19 can affect your eyes. The most common ocular side effect of COVID-19 is viral conjunctivitis. However even that is quite uncommon, as studies have noted conjunctivitis in only 1 – 3% of patients infected with coronavirus. So though COVID-19 related conjunctivitis is rare, conjunctivitis itself is a very common eye condition. Given that some people with coronavirus experience such mild symptoms, there is a small chance conjunctivitis may be the first sign of COVID-19 infection in some people. Thus it is important to be aware of the signs and symptoms of conjunctivitis, and what to do about it.
Viral Conjunctivitis
Conjunctivitis is the inflammation of the conjunctiva, the transparent tissue that covers the ‘white’ of the eye. Conjunctivitis can be caused by viruses, bacteria or allergies. In viral conjunctivitis, common symptoms include red eyes, sore, itchy or burning eyes, gritty feeling, discharge from the eye (watery or mucus) and sensitivity to light. It can affect just one eye, or both eyes.
The treatment for viral conjunctivitis varies depending on the cause and how severe it is, but it often involves some form of eyedrops either lubricating or medicated.
For people who wear contact lenses (soft or hard), it is also advised that you immediately stop wearing contact lenses during the time you have conjunctivitis. The optometrist may need to take extra treatment precautions for contact lens wearers, and they will advise you when it is safe to resume wearing your contact lenses.
Conclusion
Overall the COVID-19 pandemic is a serious global health issue. It mostly causes respiratory disease, but there can be side effects involving the eye most commonly viral conjunctivitis. The main messages to take home are:
Wash your hands frequently
Avoid touching your eyes, nose and mouth
The risk of COVID-19 spreading via the eyes seems to be very low
COVID-19 may cause viral conjunctivitis, but it is very uncommon
If you experience redness in one or both eyes, please don’t hesitate to contact us by phone or email first. We will ask you a number of questions to determine the risk of COVID-19. We will then direct you to the best care for your situation, which may be an examination with us or referral to the hospital.
Dr Katrina Chim holds a Bachelor of Optometry from UNSW with Honours. She is a full time practising optometrist in Chatswood, Sydney at Proview Optical. She has particular interest in contact lens fitting, anterior and posterior eye disease and children's vision.
Sources:
Cover Image: https://www.newscientist.com/term/covid-19/
World Health Organisation, ‘Coronavirus’ (accessed 26/03/2020)
Australian Government Department of Health ‘What you need to know about coronavirus (COVID-19)’ (accessed 26/03/2020)
World Health Organisation, ‘Basic protective measures against the new coronavirus’ (accessed 26/03/2020)
Science Daily, ‘COVID-19: Low risk of coronavirus spreading through tears’ (accessed 26/03/2020)
American Academy of Ophthalmology, ‘Alert: Important coronavirus updates for ophthalmologists’ (accessed 26/03/2020)
Optometry Australia, ‘Coronavirus may cause ocular signs and symptoms; anecdotally linked to and transmitted by conjunctivitis’ (accessed 26/03/2020)