The following is a summary of some of the latest scientific studies on the novel coronavirus and efforts to find cures and vaccines for Covod-19, the disease that caused the virus.
Vaccine responses appear weaker in the elderly
The Covid-19 vaccine from Pfizer Inc and German partner BioNTech SE stimulates weaker immune responses in the elderly compared to younger and middle-aged adults, new data suggest.
Researchers studied 91 vaccine recipients under the age of 60 and 85 recipients over the age of 80. Seventeen days after the second of two doses, nearly a third (31%) of the elderly had no antibodies. -get to be able to neutralize the virus.
This was true for just 2% of the youngest group, the researchers reported on medRxiv on Friday ahead of a peer review. Even among those under 60, only 16% had neutral antibodies after the first dose, the researchers found.
“But that does not mean that elderly people should expect real problems if they get the disease,” said coauthor Ortwin Adams of Dusseldorf University Hospital in Germany. “Recent reports from Israel, England and Scotland show that hospitalization rates and major disease progression are significantly lower than in vaccines, even in people over 80 and even after the first COVID vaccine. -19, “Adams said.
“However, it may mean that older people need to be vaccinated faster than young people to generate long-term protection. The results also suggest that referrals may still be possible. possible in some elderly people after receiving the vaccine, “he said, adding that” measures to prevent transmission effectively should continue. “
Read more: Pfizer / BioNTech Covid-19 vaccine neutralizes Brazilian variant in laboratory study
Merck’s antiviral drug may help speed up viral clearance
An experimental antiviral drug developed by Merck & Co and Ridgeback Biotherapeutics could help reduce viral loads in patients with early Covid-19, according to preliminary results from a clinical trial.
Researchers presented their findings Saturday at the 2021 Conference on Retroviruses and Fair Diseases but did not publish a formal report. In the 202-patient study, people who had been a symptom for no more than 7 days and were not hospitalized received either the oral antiviral molnupravir or a placebo.
In data from less than half of the trial participants, after five days of treatment, none of the 47 patients taking molnupravir had positive viral cultures, compared with 6 of 25 patients (24%). taking the placebo. Merck said data on the safety and effectiveness of the drug and additional secondary goals of the study will be presented at an upcoming medical meeting.
Protective memory enhances the Covid-19 vaccine response
New data suggest why some Covid-19 survivors may only need one dose of the two-dose Pfizer / BioNTech and Moderna Inc vaccines. Researchers monitored vaccine responses in 11 survivors of mild Covid-19 and 33 people who were not always ill.
Read also: WHO says flu-like illness after Covid-19 vaccine is expected
In all, the vaccines stimulated the immune system to produce antibodies along with so-called B cells that remember the virus and are still ready to produce new antibodies to fight it, although the magnitude of B cell response was lower in the elderly.
Those who had not previously had the disease “benefited from both doses,” with a further increase in antibody and B memory after the second sight, researchers reported on medRxiv Saturday ahead of a peer review. But Covid-19 survivors received large responses to the first dose with no increase in antibodies or B memory cells after the second dose.
Active levels of B memory cells before vaccination were strongly linked to their post-vaccination antibody levels, “indicating that these B cells are the most likely source” of elevated antibody levels. those who survived after just one photo, said coauthor John Wherry of the University of Pennsylvania.
This shows that B memory cells will play an important role if antibody levels fall over time, he said. Since B memory cells can be sources of new antibodies with a degree of “flexibility,” they could play a role in immunity to variable viruses, he speculated.