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By Nancy Lapid
June 25 (Reuters) - The following is a roundup of some of
the latest scientific studies on the novel coronavirus and
efforts to find treatments and vaccines for COVID-19, the
illness caused by the virus.
Vaccine-associated myocarditis tends to resolve quickly
Cases of an inflammation of the heart muscle known as
myocarditis have been reported after receiving COVID-19 shots,
mostly in young men after the second dose of the mRNA vaccines.
When myocarditis symptoms, such as chest pain and rapid or
irregular heartbeats, do occur after vaccination, they usually
resolve quickly, suggests a report of a small study published in
the journal Circulation. Doctors tracked seven male patients,
ages 19 to 39, who were hospitalized for myocarditis-like
illness not long after receiving a COVID-19 vaccine manufactured
by either Pfizer and BioNTech, Moderna
- the two mRNA vaccines - or Johnson & Johnson. All
recovered and left the hospital after two to four days of
treatment. Study co-author Dr. Christopher deFilippi of the
Inova Heart and Vascular Institute in Fairfax, Virginia, noted
that in his health system, which represents about 2 million
patients, myocarditis after COVID-19 vaccination has been a
"rare event" and "fortunately so far associated with a benign
outcome." The U.S. Centers for Disease Control and Prevention
this week said reports of the heart condition occurred at a rate
of 12.6 cases per million people who received either the
Pfizer/BioNTech or Moderna vaccines, a higher rate than would be
expected in the general population. However, deFilippi's team
advised that given the dangers of COVID-19, even for younger
adults, "the risk-benefit decision for vaccination remains
highly favorable." (https://bit.ly/35NyLRv)
Delta variant's spike fuses cells to infect them
Compared to the spike protein on earlier versions of the
coronavirus, the spike on the worrisome Delta variant is better
able to break into lung cells and fuse them together,
researchers have discovered. "Spread by cell-to-cell fusion
allows the virus to spread faster in infected people and
partially hide from the immune system," said Markus Hoffman of
Georg-August-University Göttingen in Germany, coauthor of a
report posted on Wednesday on bioRxiv ahead of peer review. "For
example, if a cell that is infected by the Delta variant is
forced (by the spike protein) to fuse with a neighboring cell
that is not yet infected, this allows the virus to enter the new
cell much faster" than if the virus particles first needed to be
released from a previously infected cell, he explained. By
spreading via cell-to-cell fusion, the virus reduces its risk of
encountering immune system cells that might attack and
inactivate it, Hoffman added. These "skills" might make the
Delta variant - first identified in India and now circulating
widely in many countries - more transmissible, and the resulting
illness more severe, the researchers said. The researchers also
found that although the Delta variant can evade antibodies, it
is not completely resistant. "It might be possible that the
Delta variant can infect people who are vaccinated (especially
if only one of two vaccine shots have been administered so far),
but vaccination is highly effective in preventing severe
disease," Hoffman said. (https://bit.ly/3A2bGIH)
Open https://tmsnrt.rs/3c7R3Bl in an external browser for a
Reuters graphic on vaccines in development.
(Reporting by Nancy Lapid; Editing by Bill Berkrot)
