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By Nancy Lapid
July 26 (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.
Most with allergy to first mRNA shot can get second dose
Most people with allergic reactions to the first dose of an
mRNA COVID-19 vaccine from either Pfizer/BioNTech
or Moderna can safely receive the second dose,
a new study shows. The rates of allergic reactions to these
vaccines have been reported to be as high as 2%, with
anaphylaxis, the most serious kind, occurring in up to 2.5 of
every 10,000 vaccine recipients, the researchers said. They
reviewed data on 189 adults with first-dose reactions to one of
these vaccines, such as flushing, dizziness or lightheadedness,
tingling, throat tightness, hives, and wheezing or shortness of
breath. Most of these adults - 84% - received the second dose of
the vaccine, with about a third taking an antihistamine
beforehand. All of them tolerated the second dose, including
those with first-dose anaphylactic reactions. Any potentially
allergic symptoms that developed after the second dose were mild
and easily controlled, the researchers reported on Monday in
JAMA Internal Medicine https://bit.ly/3iSeJLI. "Complete
two-dose vaccination has become even more important with the
Delta variant and we suspect there are many more people who did
not get their second shot because of allergic symptoms," said
coauthor Dr. Matthew Krantz from Vanderbilt University. "Our
data suggest that most patients with immediate and potentially
allergic reactions to mRNA COVID-19 vaccines tolerate a second
dose," his team concluded.
Delta may be 1,000 times more infectious than original virus
The Delta variant of the coronavirus may be over a thousand
times more infectious than the original version first identified
in Wuhan, China, a Chinese study suggests. Tracking a recent
outbreak, researchers found people infected with the Delta
variant carry 1,260 times more virus in their noses compared to
those infected in the first wave of the pandemic. The higher
load means the virus spreads far more easily from person to
person, increasing infections and hospitalizations, they
reported ahead of peer review in a paper first posted on medRxiv
earlier in July and updated on Friday https://bit.ly/3iNDQPR.
The interval between when people were exposed to infected
individuals and when they themselves were diagnosed decreased
from an average of 6 days in 2020 to 4 days during the Delta
outbreak, the researchers found. The Delta variant is
"outcompeting all other viruses because it just spreads so much
more efficiently," said Shane Crotty of the La Jolla Institute
for Immunology in San Diego, who was not involved in the Chinese
study. In the United States, Delta accounts for about 83% of new
infections, with unvaccinated people representing nearly 97% of
severe cases.
Popular antacids not linked to severe COVID-19 outcomes
Widely-used antacid medications known as proton pump
inhibitors (PPIs) are not linked with severe COVID-19 outcomes,
a new study found. Researchers with the U.S. Veterans Affairs
Health Care System analyzed data on nearly 15,000 veterans with
positive COVID-19 tests, about 42% of whom were using PPIs such
as Procter & Gamble's Prilosec (omeprazole), Takeda
Pharmaceuticals' Prevacid (lansoprazole), and
AstraZeneca's Nexium (esomeprazole). After taking
patients' underlying COVID-19 risk factors into account, the
risk of becoming sick enough to need mechanical ventilation or
to die within two months of diagnosis was no different between
regular PPI users and non-users, the researchers reported on
Sunday on medRxiv https://bit.ly/2UQdh4H ahead of peer review.
"With respect to COVID-19," the researchers concluded, "patients
and providers should feel safe to continue to use PPIs at the
lowest effective dose for approved indications."
Click for a Reuters graphic https://tmsnrt.rs/3c7R3Bl on
vaccines in development.
(Reporting by Nancy Lapid and Julie Steenhuysen; Editing by
Bill Berkrot)
