By Nancy Lapid
(Reuters) – The following is a summary of some recent studies on COVID-19. They include research that deserves further study to corroborate the findings and that has not yet been certified by peer review.
The fourth dose of vaccine protects against Omicron for at least one month
A fourth dose of Pfizer and BioNTech’s COVID-19 vaccine provided significant additional protection against severe illness, hospitalization and death for at least a month in the elderly, according to an Israeli study conducted when the Omicron variant was dominant .
The estimated efficacy of the fourth dose during days 7 to 30 after its administration compared to a third dose administered at least four months earlier was 45% against infection, 55% for symptomatic disease, 68% for hospitalization, 62% for critical illness and 74% for death, the research team reported Wednesday in the New England Journal of Medicine. The study compared 182,122 people aged 60 and over who received a fourth dose and 182,122 very similar people who received a third dose but not a fourth.
“The results of our real-world study suggest that a fourth vaccine dose is, at least initially, effective against the Omicron variant,” the researchers said. “Additional follow-up will allow for a more thorough assessment of the protection provided by the fourth dose over time.” A larger, recently published Israeli study that only looked at rates of breakthrough infections and severe illness after the fourth dose found that efficacy declined rapidly with respect to infection, but remained stable with respect to disease. serious.
COVID-19 may increase risk of rare eye clots
Patients with COVID-19 may have an increased risk of rare vision-threatening blood clots in the eyes for months afterwards, according to new findings.
Because SARS-CoV-2 infections increase the risk of blood vessel blockages at other sites in the body, researchers studied nearly half a million COVID-19 patients to see if they would develop clots in the veins or arteries of the retina, the nerve tissue at the back of the eye that receives images and sends them to the brain. Over the next six months, 65 patients had retinal vein occlusion. While the number is low, it reflects a statistically significant 54% increase over pre-COVID infection rates, according to a report published Thursday in JAMA Ophthalmology. Retinal artery clots were 35% more common after COVID-19 than before, but this difference could be due to chance. The clots most often occurred in patients with other conditions that increased their risk of blood vessel problems, such as diabetes, high blood pressure and high cholesterol.
Clot risk does not appear to be associated with severity of coronavirus infection. The study cannot prove that COVID-19 caused the clots in the eyes of these patients, the researchers noted, saying larger studies of the issue are needed.
Risk of infectious breakthroughs linked to psychiatric problems
People with mental health issues are at higher risk of breakthrough infections after receiving COVID-19 vaccines, new data shows.
California researchers have followed more than a quarter of a million fully immunized patients in the US Veterans Health System. Almost all were men and about half had received at least one psychiatric diagnosis in the past five years. Overall, 14.8% developed COVID infections despite vaccination. Compared to study participants without a psychiatric diagnosis, people over the age of 65 with substance abuse, psychotic disorders, bipolar disorder, adjustment disorder or anxiety faced a risk of up to 24%. higher in breakthrough infections, according to the study. For those under 65, the risks were up to 11% higher than for those without a psychiatric history, the researchers reported Thursday in JAMA Network Open.
“Our research suggests that the increase in breakthrough infections in people with psychiatric disorders cannot be fully explained by socio-demographic factors or pre-existing conditions,” said study leader Aoife O’Donovan of the San Francisco VA Health Care System. “It is possible that post-vaccination immunity wanes faster or more steeply for people with psychiatric disorders and/or they might have less protection against new variants.”
For a Reuters graphic on vaccines in development, click: https://graphics.Reuters.com/HEALTH-CORONAVIRUS/VACCINE-TRACKER/xegpbqnlovq/
(Reporting by Nancy Lapid; Editing by Bill Berkrot)