‘Dark spots’: COVID jab tied to rare health symptom

A rare side effect from COVID-19 vaccines has caught the attention of health experts, after a number of people reported unusual symptoms.

New research is calling for further study on a possible link between COVID-19 jabs and long-term vision issues.

While vaccines have been vital in fighting the pandemic, emerging data could mean we’re not out of the woods yet.

Between January 2021 and January 2023, 20 peer-reviewed studies looked into eye problems reported by 243 people aged 18 to 84 who had received COVID-19 vaccines.

Almost half of these patients - 42 per cent - had the Pfizer-BioNTech jab, which was the main vaccine rolled out in Australia, the USA, the UK, and much of Europe.

What jumps out is inflammation. Nearly half of the patients reported experiencing ocular inflammatory conditions like uveitis, an irritation deep inside the eye.

Another 24 per cent were said to have suffered optic neuritis, a swelling of the optic nerve that can cause pain and threaten vision.

Herpetic eye disease, caused by the herpes virus attacking the eye, showed up in 14 per cent of cases, triggering redness, pain, and discomfort.

About 10 per cent documented retinal circulation issues - blockages in the eye’s arteries or veins that can trigger sudden vision loss.

And there were also a few rare cases where patients were noted to exhibit retina-related problems causing “dark spots” or “blind patches”.

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None of the study participants reported immediate vision problems. Picture: iStock

But the most notable observations come from a recent Turkish study that tracked 64 patients before and after their two mRNA vaccine doses.

Using detailed eye scans, researchers found an 8 per cent drop in the cornea’s endothelial cell count - the cells responsible for keeping the cornea clear.

These cells don’t regenerate, and losing too many can permanently impair vision.

To put that into perspective, healthy adults usually have between 2000 and 3000 of these cells per square millimetre.

After vaccination, the average dropped from 2597 to 2378.

While these numbers are still considered safe for most, the decline could be a warning sign for people with pre-existing eye conditions or those who have had eye surgeries like LASIK, cataract removal, or corneal transplants.

Researchers also noted that corneas thickened by around 2 per cent after vaccination - a sign of possible swelling.

The honeycomb shape of the endothelial cells became distorted, and the size differences between individual cells increased, which are both signs of cellular stress.

Though none of the study participants reported immediate vision problems, experts warn that long-term structural changes to the cornea could lead to lasting damage, especially in vulnerable patients.

Dr Fatma Sümer and Sevgi Subasi, authors of the study published in Ophthalmic Epidemiology, stressed the need for careful observation: “The endothelium should be closely monitored in those with a low endothelial count or who have had a corneal graft.”

Eye complications after vaccination are rare. Picture: iStock

According to Healthline, eye complications after vaccination are rare and appear to be driven by an overactive immune response.

Symptoms can include blurred vision, light sensitivity, redness, eye pain, shingles around the eye, or reactivated herpes infections.

In even rarer cases, the immune system may reject a previously transplanted cornea, risking vision loss and graft failure.

This means the transplanted cornea loses its clarity and function, leading to impaired vision and the potential need for further treatment or surgery.

These findings are not conclusive, and experts do not advise people to skip their COVID vaccine shots — far from it.

But they are urging doctors and patients to not ignore these subtle warning signs.

Those who have had prior eye surgery, suffer from chronic eye disease, or notice persistent blurry vision after vaccination are advised to be checked, because even small changes inside your eyes can have big consequences down the road

According to safety reports from the Therapeutic Goods Administration (TGA), “vaccination is the most effective way to reduce deaths and severe illness from infection.”

Like all medicines, the TGA notes, “COVID-19 vaccines may cause some side effects.

“The most frequently reported include injection-site reactions (such as a sore arm) and more general symptoms, like headache, muscle pain, fever and chills.”

The TGA closely monitors reports of adverse events to the COVID-19 vaccines and emphasises that “the protective benefits of vaccination far outweigh the potential risks.”