By Nancy Lapid
May 5 (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.
Pfizer/BioNTech vaccine appears not to affect sperm
The COVID-19 mRNA vaccine from Pfizer Inc and
BioNTech SE does not damage sperm, according to a study
by Israeli researchers. They collected sperm samples from 43
male volunteers before and roughly a month after the men were
vaccinated. None of their sperm parameters - volume,
concentration, or motility - had changed significantly after
vaccination, the researchers reported Monday on medRxiv ahead of
peer review. "These preliminary results are reassuring to the
young male population undergoing vaccination worldwide," the
researchers said. "Couples desiring to conceive should
vaccinate, as vaccination does not affect sperm," whereas
previous studies have shown that coronavirus infection does
affect sperm adversely. (https://bit.ly/3nPTwnL)
Neuropsychiatric symptoms persist in COVID-19 survivors
Neuropsychiatric symptoms are common in COVID-19 survivors,
a large new analysis confirms. Researchers pooled data from 51
studies involving a total of nearly 19,000 patients who were
tracked for up to six months. The average follow-up was 77 days
post-diagnosis. Overall, 27.4% reported sleep problems, 24.4%
had fatigue, 20.2% scored poorly on objective tests of
cognition, 19.1% reported anxiety, and 15.7% had post-traumatic
stress. Nerve disturbances and dizziness or vertigo were less
common but were seen in "a non-negligible proportion" of
patients, the research team reported on Tuesday in a paper
posted on medRxiv ahead of peer review. Only about 7% of the
patients were said to have required intensive care, based on
this meta-analysis in which some papers were not clear on
intensive care figures. "There was little or no evidence of
differential symptom prevalence based on hospitalization status,
severity, or follow-up duration," the researchers said. They
caution that some of the patients may still have been in the
acute phase of their infections, and longer follow-up will be
necessary to know how long these problems persist, and whether
they are effects of viral infection in general or are specific
to the new coronavirus. (https://bit.ly/3b2OVtz)
Vaccines protect unvaccinated household members, too
Compared to an unvaccinated COVID-19 patient, a vaccinated
person who nevertheless becomes infected with the coronavirus
has a much lower risk of transmitting the virus to household
members, a large UK study found. Researchers at Public Health
England studied more than 365,000 households with a first
COVID-19 infection, including more than 24,000 households in
which the so called "index case" of COVID-19 was someone who had
received at least one dose of either the Pfizer/BioNTech vaccine
or the Oxford-AstraZeneca vaccine. When the first dose
had been given at least 21 days previously - as was the case in
4,107 of the households studied - the risk of virus transmission
from vaccinated individuals to their household members was 40%
to 50% lower than the risk of transmission from COVID-19
patients who had not been vaccinated, the researchers found. The
effects were similar for both the Pfizer and AstraZeneca
vaccines and started to become evident around 14 days after the
first dose, according to a report posted ahead of peer review on
Knowledge Hub. Along with the vaccines' success at preventing
infections and reducing the severity of infections that do
occur, the new findings show they are "associated with reduced
likelihood of household transmission ... highlighting important
wider benefits to close contacts," the authors conclude. (https://bit.ly/3nMeOmx;
https://reut.rs/3vANf2a)
COVID-19 nasal swab test complications extremely rare
Severe complications associated with nasal swab tests for
COVID-19 are very rare, a new study found. Researchers in
Finland looked at six months of hospital emergency department
data in a region where more than 640,000 such tests had been
performed. They found that only eight patients needed emergency
care for swab test-related problems. Four of the eight cases
were due to broken swabs and four to uncontrollable nosebleeds.
All of the complications occurred immediately after swab tests,
according to a report published on Thursday in JAMA
Otolaryngology-Head & Neck Surgery. The overall rate was 1.24
emergencies for every 100,000 performed tests. While the study
may have missed minor complications, it showed that COVID-19
nasopharyngeal swab testing "is safe and complications are
extremely rare," said coauthor Dr. Anni Koskinen of the
University of Helsinki. All of the complications seemed to
involve an incorrect sampling technique or misdirection of the
swab, her team reported. "Force should never be used, especially
in patients with known prior operations of the nose or skull
base," they advised. (https://bit.ly/3gYSTXR)
Open https://tmsnrt.rs/3c7R3Bl in an external browser for a
Reuters graphic on vaccines in development.
(Reporting by Nancy Lapid and David Douglas; Editing by Bill
Berkrot)
Astrazeneca (AZN)
