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By Nancy Lapid
June 14 (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.
Delta variant doubles risk of COVID-19 hospitalization
The delta variant of the coronavirus first identified in
India may double the risk of hospitalization among COVID-19
patients, compared with the alpha variant first discovered in
the UK, a study from Scotland suggests. Researchers looked at
19,543 COVID-19 cases and 377 hospitalizations among 5.4 million
people, including 7,723 cases and 134 hospitalizations in
patients with the delta variant, who tended to be younger and
more affluent. The risk of COVID-19 hospital admission was about
double with the delta variant compared to the alpha variant,
with the risk particularly increased in those with five or more
medical conditions known to contribute to more severe disease,
the researchers reported on Monday in The Lancet. They found
that two doses of the vaccines from Pfizer and BioNTech
and from AstraZeneca still provide strong
protection, although not as strong as the protection provided
against the alpha variant. Two weeks after the second dose, the
Pfizer/BioNTech vaccine was found to provide 79% protection
against infection from the delta variant, compared to 92%
against the alpha variant. With AstraZeneca's vaccine, there was
60% protection against delta compared with 73% for alpha.
Because this was an observational study, more research is needed
to confirm the findings, the research team said. (https://bit.ly/3xinW5K)
Novavax vaccine highly effective in North American trial
Novavax Inc on Monday said its COVID-19 vaccine was
more than 90% effective, including against a variety of
concerning coronavirus variants, in a large, late-stage
clinical trial, providing another potential weapon against the
disease once approved for use. In the trial involving nearly
30,000 volunteers in the United States and Mexico, the two-shot
vaccine was 100% effective in preventing infection by the
original version of the coronavirus, the company said. It was
more than 93% effective against the predominant variants of the
virus that have been of concern among scientists and public
health officials. The alpha variant first identified in the UK
was the predominant variant in the United States while the trial
was being conducted, the company said. The vaccine was 91%
effective among volunteers at high risk of severe infection and
100% effective in preventing moderate and severe cases of
COVID-19. Novavax said the vaccine was generally well tolerated,
with side effects similar to those seen with existing COVID-19
vaccines. The Novavax COVID-19 shot is a more conventional type
of vaccine than those currently available. It contains an actual
version of the virus' spike protein that cannot cause disease
but can trigger the immune system directly. The company said the
results put it on track to file for emergency authorization in
the United States and elsewhere in the third quarter of 2021. (https://reut.rs/3iEvUlw)
Tetanus, diphtheria boosters tied to less severe COVID-19
Older individuals who have gotten a diphtheria or tetanus
vaccine booster shot in the last 10 years may be at lower risk
for severe COVID-19, a new study suggests. Using a large UK
registry, researchers looked back at 10 years of immunization
records from 103,409 participants with an average age of 71.
They saw a trend toward a lower risk of a positive COVID-19 test
in people who had gotten a tetanus or diphtheria booster shot
during the study period, although the difference was small and
might have been due to chance. There was, however, a
statistically significant association between the booster shots
and the odds of severe COVID-19. After accounting for age, sex,
underlying respiratory diseases, and socioeconomic status, the
odds of developing severe COVID-19 were 64% lower in people who
had gotten a diphtheria booster and 50% lower in recipients of
tetanus booster, according to a report posted on medRxiv on
Saturday ahead of peer review. The study does not prove cause
and effect. If there is some effect of the boosters, it might be
that they protect against severe COVID-19 symptoms by
stimulating the immune system, the authors suggest. "The
possibility that these vaccinations may influence the severity
of COVID-19 warrants follow-up investigations," they conclude.
(https://bit.ly/2SBSVLg)
Open https://tmsnrt.rs/3c7R3Bl in an external browser for a
Reuters graphic on vaccines in development.
(Reporting by Nancy Lapid, Carl O'Donnell and Alistair Smout;
Editing by Bill Berkrot)
