The following is a summary of some recent studies on COVID-19. They include research that warrants further study to corroborate the findings and that have yet to be certified by peer review.
Heart attack patients with COVID-19 have lower survival rate
The odds of surviving a heart attack are significantly lower when a person also has COVID-19, even though such patients tend to be generally younger than typical heart patients, a new study found. The researchers reviewed data on more than 80,000 people who had heart attacks in the United States in 2019 or 2020.
Most of them - about 76,000 - had heart attacks at home or at work, or in some other community setting. In this group, 15.2% of those with COVID-19 later died in the hospital, compared to 11.2% of heart attack patients without COVID-19.
Among the roughly 4,000 patients who were already hospitalized when the heart attack occurred, 78.5% of those with COVID-19 died, compared to 46.1% of those without COVID-19, according to a report published on Friday in JAMA.
Overall, the COVID-19 heart attack patients were more likely to have gone into cardiac arrest - when the heart stops beating - and less likely to undergo procedures to reopen clogged heart arteries, the researchers found.
They said more research is needed to understand why a diagnosis of COVID-19 increases the risk for death in patients having heart attacks.
Early Israeli data support Pfizer booster
Early data on the efficacy of a booster dose of the COVID-19 vaccine from Pfizer Inc and partner BioNTech SE announced by the Israeli Health Ministry and now published in a peer-reviewed journal suggest a sharp reduction in risk of severe infections soon after administration.
Pfizer has said that its vaccine's efficacy wanes over time. From late July through late September, when the Delta variant was predominant, researchers tracked more than 1.4 million people who had received two doses of the vaccine at least five months earlier, half of whom had also gotten a third dose at least a week before being enrolled in the study.
As reported on Friday in The Lancet, those who received the booster had a 93% lower risk of COVID-19-related hospitalization, a 92% lower risk of severe illness, and 81% lower risk of COVID-19-related death.
The average age in the study was 52. Both groups - boosted and unboosted - had similar lifestyles and health status. As it was not a randomized controlled trial, the data cannot prove cause and effect.
And how long any extra protection lasts is not yet clear, given that no one was tracked for more than two months, and half were tracked for less than two weeks.