The World Health Organisation has since updated their list of ‘less common’ symptoms of the disease to include conjunctivitis and red eyes, as recent reports have suggested a link between conjunctivitis, coronavirus (Sars-Cov-2) and the corresponding disease, COVID-19.1
To help you understand the latest research around coronavirus, and what conditions may place someone at higher risk of contracting it, we’ve put together this guide.
Can coronavirus be contracted through the eyes?
The conjunctiva is a mucous membrane which covers the surface of the eye. If viral particles, such as the coronavirus, come into contact with it (for example, from a sneeze, cough or touching your eyes with unclean hands), this could result in an individual becoming infected.
This is because coronavirus latches onto ACE-2 receptors on the cells of the conjunctiva, similar receptors are found in the respiratory tract and lungs. These cell surface receptors act as a gateway into cells themselves, leading to the virus entering the body3.
Can conjunctivitis cause COVID-19?
No, there is no research evidence to suggest that conjunctivitis can cause COVID-19 itself.
Is conjunctivitis a symptom of COVID-19?
Coronavirus can cause conjunctivitis, however it’s quite rare — occurring in about 1-3 % of affected people and is on the less frequent symptoms list by WHO. Conjunctivitis associated with COVID-19 tends to occur in the later stages of the disease, alongside more common symptoms such as a continuous cough and fever.
One study on children hospitalised with COVID-19 in China found that those with common COVID-19 symptoms (such as a cough) were also more likely to develop ocular symptoms of conjunctivitis4.
Does conjunctivitis place me at higher risk of contracting COVID-19?
No, there is no scientific evidence to suggest having conjunctivitis places you at higher risk of developing COVID-19.
Is it possible to have conjunctivitis and COVID-19 unknowingly?
Conjunctivitis associated with COVID-19 tends to occur in the later stages of the disease, so you will most likely be showing other common symptoms of coronavirus alongside it. Typical symptoms of conjunctivitis include:
- Bloodshot eyes
- Burning or gritty feeling
- Discharge from one or both eyes
- Pus that sticks to the eyelashes
- Itchiness and redness
- Excessive watering
If you're worried that you might be experiencing some of these symptoms, get in touch with your local store team for advice.
What information sources can I trust regarding conjunctivitis?
There is a lot of misinformation circulating about coronavirus and its link to a number of eye conditions. If you’re ever unsure about which information to trust, the official government website is a helpful and reliable resource to consult.
What information sources can I trust regarding conjunctivitis?
There is a lot of misinformation circulating about coronavirus and its link to a number of eye conditions. If you’re ever unsure about which information to trust, the HSE Ireland website is a helpful and reliable resource to consult2.
I have conjunctivitis and I suspect I have COVID-19 — what should I do?
If you think you might have COVID-19, then you should begin following official Government self-isolation guidelines. Conjunctivitis usually gets better within a couple of weeks without treatment, although there are things you can do to help ease your symptoms:
Boil some water and then let it cool down. Soak a clean cotton wool pad (1 for each eye) in the water and:
- Gently rub your eyelashes to clean off any crust or build-up
- Hold a cold flannel on your (closed) eyes for a few minutes to cool them down and ease the inflammation
- Do not wear contact lenses until your eyes are better
How to prevent conjunctivitis
There are a number of different causes of conjunctivitis and it’s usually a common, mild eye condition. Whilst there are many causes of conjunctivitis, the main ones are usually viruses and bacteria.
To reduce the likelihood of contracting conjunctivitis, you should avoid touching your face and eyes, maintain good general levels of hygiene, and regularly wash your hands. Take a look at the NHS handwashing guidelines for more information on how to do this correctly.
To limit the spread of conjunctivitis it’s advisable to not rub your eyes or share pillows and towels. Such items should be laundered with detergent at a high temperature regularly and, as ever, hand washing should be regular.
Sometimes the cause of conjunctivitis can be an allergy or even from a dusty environment which doesn’t have the same infective risk. Hay-fever is actually a type of allergic conjunctivitis. For the latest updates and eyecare guidance during coronavirus, visit our COVID-19 resource.
Last year "conjunctivitis" was the 5th most searched eye health term.
- World Health Organisation (2021). Coronavirus [online]. Available at: https://www.who.int/health-topics/coronavirus#tab=tab_3 [accessed 18 February 2021]
- HSE Ireland. Conjunctivitis [online]. Available at: https://www.hse.ie/eng/health/... [accessed 8 April 2020]
- Lingli Zhou, Zhenhua Xu, Gianni M. Castiglione, Uri S. Soiberman, Charles G. Eberhart, Elia J. Duh. (2020). ACE2 and TMPRSS2 are expressed on the human ocular surface, suggesting susceptibility to SARS-CoV-2 infection [online]. Available at: https://www.biorxiv.org/conten... [accessed 26 May 2020].
- Ma N, Li P, Wang X, et al. (2020) Ocular Manifestations and Clinical Characteristics of Children With Laboratory-Confirmed COVID-19 in Wuhan, China. JAMA [online]. Available at: https://jamanetwork.com/journals/jamaophthalmology/fullarticle/2769877 [accessed 18/09/2020]
Moorfields (no date) Conjunctivitis [online]. Available at: https://www.moorfields.nhs.uk/condition/conjunctivitis [accessed 7 April 2020]
The New England Journal of Medicine (2020). Clinical Characteristics of Coronavirus Disease 2019 in China [online]. Available at: https://www.nejm.org/doi/pdf/10.1056/NEJMoa2002032 [accessed 7 April 2020]
Yunyun Zhou, Yuyang Zeng, Yongqing Tong, ChangZheng Chen (2020). Ophthalmologic evidence against the interpersonal transmission of 2019 novel coronavirus through conjunctiva [online]. Available at: https://www.medrxiv.org/content/10.1101/2020.02.11.20021956v1 [accessed 7 April 2020]