Latest news with #OphthalmicEpidemiology
Daily Record
a day ago
- Health
- Daily Record
Pfizer Covid-19 vaccine linked to eye problems that could damage vision in new study
Researchers looked at how the vaccine affected patients' corneas - the clear front part of the eye that allows light to come in Scientists have found that Pfizer's COVID-19 vaccine may increase the risk of serious eye damage, potentially leading to loss of sight, according to a recent study. The new research conducted by Turkish scientists specifically examined how the jab affected patients' corneas - the transparent front part of the eye that lets light in. In 64 subjects, changes in the inner layer of the cornea, known as the endothelium, were measured before receiving the first Pfizer dose and two months after the second. The results indicated that having two doses of the vaccine led to thicker corneas, fewer endothelial cells in the eye, and more variation in the size of these specialised cells that form the endothelium. In the short term, these alterations suggest the Pfizer vaccine might temporarily weaken the endothelium, even though patients didn't experience noticeable vision problems during the study. For individuals with healthy eyes, these minor changes likely won't impact vision immediately. However, scientists stated that if these changes persist for years, they could result in corneal swelling or blurred vision, particularly in those with pre-existing eye conditions or individuals who have undergone a corneal transplant. A thicker cornea and reduced cell density may contribute to eye conditions like corneal oedema, bullous keratopathy, or corneal decompensation, which can all lead to permanent vision loss in severe cases, especially if left untreated, reports the Express. The researchers cautioned in the study, published Wednesday (July 16) in the journal Ophthalmic Epidemiology: "The endothelium should be closely monitored in those with a low endothelial count or who have had a corneal graft." Nevertheless, the team did not advise against the Pfizer jab and will still require long-term studies on additional patients' vision to determine if these alterations persist months and years following the injections. A representative from Pfizer UK stated they regarded the findings "very seriously". In a statement to the Express, they said: "Patient safety is paramount and we take any reports of adverse events very seriously. Adverse event reports do not imply causality, and in the context of vaccination such events may be unrelated to administration of the vaccine. "Hundreds of millions of doses of the Pfizer-BioNTech COVID-19 vaccine have been administered globally and the benefit-risk profile of the vaccine remains positive for all authorised indications and age groups. "As with every medicine and vaccine, including the Pfizer-BioNTech COVID-19 vaccine, Pfizer has robust processes to meet its regulatory responsibilities to closely monitor, report and analyse all adverse events, and collect relevant information to assess any new potential safety risks that may be associated with the COVID-19 vaccine." Pfizer said as well as their pharmacovigilance efforts and compliance with regulatory requirements related to quality and safety, they also work with regulatory authorities to independently monitor the safety profile of the vaccine. Join the Daily Record WhatsApp community! Get the latest news sent straight to your messages by joining our WhatsApp community today. You'll receive daily updates on breaking news as well as the top headlines across Scotland. No one will be able to see who is signed up and no one can send messages except the Daily Record team. All you have to do is click here if you're on mobile, select 'Join Community' and you're in! If you're on a desktop, simply scan the QR code above with your phone and click 'Join Community'. We also treat our community members to special offers, promotions, and adverts from us and our partners. If you don't like our community, you can check out any time you like. To leave our community click on the name at the top of your screen and choose 'exit group'. If you're curious, you can read our Privacy Notice. In any case, patients who receive the COVID-19 vaccine "should talk to their doctor, pharmacist or nurse if they have any concerns or experience any side effects" - including any possible side effects not listed in the package leaflet. "As with all medicines and vaccines... Pfizer has stringent procedures in place to fulfil its regulatory obligations to closely monitor, report, and analyse all adverse events, as well as gather pertinent information to evaluate any new potential safety risks that may be associated with the COVID-19 vaccine," the spokesperson added.
Daily Mail
3 days ago
- Health
- Daily Mail
Covid shot linked to vision loss in rare cases
A study has linked a Covid shot with vision loss. It found that Pfizer 's vaccine can adversely affect the cornea, which allows light to enter the eye. At its worst this could lead to corneal swelling or blurry vision, especially in those who already suffer from eye problems or have had a cornea transplant. In 64 people, scientists in Turkey measured changes in the cornea's inner layer, called the endothelium, before taking the first Pfizer dose and two months after receiving the second. Results revealed that taking both doses of the vaccine led to thicker corneas, fewer endothelial cells in the eye and more variation in size of these specialized cells that form the endothelium. In the short term, these changes suggest the Pfizer vaccine may temporarily weaken the endothelium, even though patients didn't suffer clear vision problems during the study. For people with healthy eyes, these small changes likely won't affect vision right away. However, if scientists find that these changes last for years, they could lead to corneal swelling or blurry vision, especially in those with pre-existing eye problems or people who have had a cornea transplant. A thicker cornea and reduced cell density could contribute to eye conditions like corneal edema, bullous keratopathy, or corneal decompensation, which can all cause permanent vision loss in severe cases, especially if left untreated. The researchers warned in the study, published Wednesday in the journal Ophthalmic Epidemiology: 'The endothelium should be closely monitored in those with a low endothelial count or who have had a corneal graft.' An eye doctor can use a special microscope called specular microscopy to find out if someone has a low endothelial cell count. If you have blurry vision or eye discomfort, this test can also check if your cornea's cells are healthy. A low count can be the result of aging, eye diseases like Fuchs' dystrophy, eye surgeries, injuries, or infections. These factors damage the cells that keep your cornea clear, and they don't grow back. Specifically, the team found that the Pfizer-BioNTech vaccine caused a patient's cornea to go from 528 to 542 micrometers in thickness, or roughly 0.0208 inches to 0.0213 inches. This is a roughly two-percent increase in micrometers. A slightly thicker cornea isn't automatically harmful. The cornea can thicken temporarily due to inflammation, fluid buildup, or stress on the endothelium from minor illnesses or injuries to the eyes. If it stays too thick for months or years, however, it could make the cornea less clear, potentially affecting vision. The team did not recommend against vaccination and will still need to conduct long-term testing on patients to see if these changes continue to appear months and years after taking the shots. The average number of endothelial cells, which keep the cornea clear by pumping out excess fluid, dropped from 2,597 to 2,378 cells per square millimeter in the study, a loss of about eight percent. Normal endothelial cell counts range from 2,000 to 3,000 cells per square millimeter in healthy adults, so 2,378 is still within a safe range for most people. However, for someone with a low cell count to start with, due to a previous eye surgery, infection, or disease, this loss could be riskier for their vision. Researchers also discovered that these cells became less uniform after the vaccination, with their coefficient of variation - each cell's difference in size - increasing from 39 to 42. When cells die, nearby cells stretch to fill the gaps, leading to bigger differences in size. This could mean the endothelium is less healthy. If this trend continued for years, it could affect the cornea's clarity. After vaccination, the study found fewer cells kept their healthy six-sided shape, with the total dropping from 50 to 48 per cent of the cells in the eye. Healthy endothelial cells are usually shaped like hexagons, which allows them to fit together tightly, like a honeycomb. Although the two per cent drop was not a direct sign of damage, it suggested to the team that the cells might be reacting to some sort of stress over those two months to three months. Researchers said their results also showed evidence that the changes had a high likelihood of being directly linked to taking the vaccine, meaning it wasn't just a random anomaly in the testing. If the signs of stress and inflammation drop off shortly after receiving the Pfizer shot, the impact of these minor changes would not be overly harmful. To find these results, the team studied 128 eyes, 64 pairs in total, before each person received their Covid vaccinations. They followed up with the group approximately 75 days after they got their second dose of the Pfizer-BioNTech vaccine. The team used a machine called Sirius corneal topography to measure the corneas' thickness and shape, and another device, the Tomey EM-4000 specular microscope, to take detailed pictures of the endothelial cells to check their number, size and shape. Each participant also took a full eye exam, including tests for vision sharpness, eye pressure and scans of the eye's front and back parts to ensure overall eye health. By comparing the measurements taken before vaccination to those after, the researchers could see if the Pfizer vaccine was influencing the health of the eyes. The new data on potentially harmful side-effects linked to Pfizer's Covid vaccine added to a growing list of concerns the Trump Administration has highlighted. In May, the US Food and Drug Administration (FDA) forced Pfizer and Moderna to use expanded warning labels about the risks of heart damage tied to Covid-19 vaccines. The shots previously included warning labels about the rare chance of patients suffering myocarditis, inflammation of the heart muscle, and pericarditis, inflammation of the sac-like lining surrounding the heart. The new labels expanded that warning to certain age groups, particularly men between the ages of 16 and 25. Researchers found that this seemingly healthy group appeared to be at the highest risk of the rare complications.
Arab Times
3 days ago
- Health
- Arab Times
New study links COVID-19 vaccine to potential eye damage
NEW YORK, July 19: A new scientific study has found that Pfizer's COVID-19 vaccine may cause temporary changes in the eyes' corneal structure, raising concerns about long-term vision health, particularly for individuals with pre-existing eye conditions. Researchers in Turkey studied 64 participants who received both doses of the Pfizer-BioNTech vaccine and discovered measurable changes to the cornea's innermost layer, known as the endothelium. This thin cell layer is vital for keeping the cornea clear by pumping out excess fluid. The study was published Wednesday in the journal Ophthalmic Epidemiology. The scientists observed that, within two months of vaccination, participants showed a slight thickening of the cornea, a decrease in endothelial cell count, and greater variability in the size of these cells — all potential signs of short-term stress on the eye. 'These changes suggest the vaccine may temporarily weaken the endothelium, though none of the participants experienced vision problems during the study,' the researchers noted. The average corneal thickness increased from 528 to 542 micrometers — about a 2% change. Meanwhile, endothelial cell density dropped from an average of 2,597 to 2,378 cells per square millimeter — an 8% decrease. While this remains within normal limits for healthy adults, the decline could pose a risk for people with already low cell counts, such as those with prior eye surgeries, infections, or conditions like Fuchs' dystrophy. The study also found a drop in the proportion of endothelial cells with a healthy hexagonal shape, from 50% to 48%, and an increase in the coefficient of variation in cell size from 39 to 42 — further indicators of stress or damage. 'These changes are subtle and may not cause immediate harm, but they warrant monitoring, especially in individuals with compromised corneal health,' the authors stated. The research team did not recommend against COVID-19 vaccination but emphasized the need for further long-term studies to determine whether the observed changes persist or worsen over time. 'If these effects on the endothelium continue for years, they could contribute to eye diseases such as corneal edema, bullous keratopathy, or corneal decompensation — all of which can lead to permanent vision loss if left untreated,' the study warned. Specialists recommend that people with eye discomfort or blurry vision consult an ophthalmologist. A non-invasive test using a specular microscope can determine endothelial cell health. The study adds to a growing list of side-effect concerns linked to COVID-19 vaccines. In May, the U.S. Food and Drug Administration (FDA) expanded its warning labels on Pfizer and Moderna vaccines to include risks of myocarditis and pericarditis — types of heart inflammation — particularly in males aged 16 to 25. Despite these concerns, health authorities maintain that the benefits of COVID-19 vaccination continue to outweigh the risks for the majority of the population. The Turkish study involved 128 eyes (64 participants), with each subject undergoing full ophthalmic examinations before receiving their first vaccine dose and approximately 75 days after their second. Researchers used high-precision tools — including Sirius corneal topography and the Tomey EM-4000 specular microscope — to assess corneal thickness and endothelial cell characteristics.
Time of India
3 days ago
- Health
- Time of India
Pfizer COVID vaccine may cause serious eye damage, new study reveals
A recent study has raised concerns that the Pfizer-BioNTech COVID-19 vaccine may cause subtle but potentially serious effects on the eye's cornea, particularly its innermost layer, the endothelium. Conducted by scientists in Turkey and published in the journal Ophthalmic Epidemiology, the research examined changes in the corneas of 64 patients before and after receiving both doses of the vaccine. While no immediate vision loss was reported, the study found that the vaccine led to thicker corneas, a reduced number of endothelial cells, and structural changes that could affect eye health over time. According to the Daily Mail, experts caution that while these changes may be harmless in the short term, they could pose risks for those with pre-existing eye conditions or corneal transplants. Pfizer COVID vaccine linked to corneal cell loss, swelling and altered structure Researchers found that the average thickness of the cornea increased from 528 to 542 micrometers after two Pfizer doses, a roughly 2 percent rise. The endothelial cell count, responsible for keeping the cornea clear, dropped by about 8 percent, from 2,597 to 2,378 cells per square millimeter. Though this remains within a safe range for healthy individuals, such a decline could pose serious risks for those with a low baseline count due to aging, eye surgeries, or diseases like Fuchs' dystrophy. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like Hear better, live easier Amplifon Book Now Undo In addition, the study noted an increase in cell size variation (coefficient of variation), rising from 39 to 42, suggesting the corneal endothelium was under stress. The number of cells maintaining a healthy hexagonal shape also dropped from 50 percent to 48 percent. As Daily Mail reported, these signs may not immediately affect vision but could compromise the cornea's long-term clarity and function if they persist. Scientists urge caution but do not oppose vaccination The study, which analyzed 128 eyes using Sirius corneal topography and Tomey EM-4000 specular microscopy, does not recommend halting vaccination efforts. Rather, it calls for ongoing monitoring of corneal health in individuals with known eye vulnerabilities. The researchers emphasized that the changes observed might be temporary responses to stress or inflammation and could resolve over time. Still, they warned that 'the endothelium should be closely monitored in those with a low endothelial count or who have had a corneal graft,' especially if future studies confirm long-term damage. According to Daily Mail, this adds to existing concerns over rare side effects of mRNA vaccines, including myocarditis and pericarditis, particularly in younger men. The researchers plan to continue tracking participants to determine if these early corneal changes progress or stabilize over time.
