#Coronavirus #コロナウイルス Vol.29(Delta variant, etc. デルタ変異株など)

All the below links are in English. Excerpts are on our own.


Youth, Delta variant behind UK COVID surge (06/17/2021) | @CIDRAP
… In total, 135 of 108,911 swabs tested positive for COVID-19, for a weighted prevalence of 0.15%, up from 0.10% of swabs collected from Apr 15 to May 3. Northwest England had the highest prevalence (0.26%), while the country’s southwest region had the lowest (0.05%). Residents of socioeconomically disadvantaged areas were at nearly double the risk of testing positive, compared with those in less-deprived areas.
Young people are behind the surge, with a 5-fold higher rate of COVID-19 test positivity among children 5 to 12 years (0.35% prevalence) and adults 18 to 24 (0.36% prevalence) than in those 65 or older. People younger than 50 were 2.5 times more likely to be infected than older people (prevalence, 0.20% vs 0.08%), although the researchers noted that infections seem to be growing at a comparable rate in both age-groups. …
In early February, the link between COVID-19 infection rates and hospitalizations started to lessen, apparently due to vaccinations, only to reemerge in late April. When the researchers stratified data by age, however, they found that those 65 and older still had a lower association between infections and hospital admissions.
“We can take a lot of comfort in the fact that there does appear to be very good protection in the older age groups, where virtually everyone has been doubly vaccinated,” senior study author Paul Elliott…
… Delta has become dominant in the country, rising from 60% of positive COVID-19 tests at the beginning of the study to 90% by the end. …
… it’s very difficult to predict the duration of the exponential phase,” lead author Steven Riley… noting that extending coronavirus vaccination to younger people in the next month should slow the surge. …
… Riley adds, “Even though we are seeing the highest infection prevalence in younger people who are less susceptible to COVID-19, if this growth continues it will drive up infections in older, more vulnerable people, as the vaccines are not 100% effective and not everyone has been fully vaccinated. This would lead to more hospitalisations and deaths, and risks straining the NHS …
… a team led by University of Oxford researchers evaluated whether vaccines, monoclonal antibodies, or antibodies derived from COVID-19 survivors could neutralize the Delta variant’s B1617.1 and B1617.2 sublineages.
The researchers found substantial reductions in the ability of the AstraZeneca/Oxford and Pfizer/BioNTech vaccines to inactivate the Delta variant, although the viruses weren’t broadly able to escape neutralization.
The ability of the Pfizer vaccine to neutralize the Delta variant dropped 1.34-fold between 4 and 10 weeks after the first dose, at which time the ability was nearly lost. “Recently in the UK some reduction in Pfizer-BioNTech effectiveness has been detected at 10 weeks, presumably as a result of waning immunity, leading to the recommendation that the second vaccine dose interval should be reduced from 12 to 8 weeks in those over age 50,” the authors said.
The researchers noted previous studies that found lower vaccine effectiveness against mild to moderate COVID-19 in countries in which Beta (B1351) was dominant, as well as against the Alpha (B117) variant first seen in England, although protection against severe illness was maintained.
Overall, convalescent sera was 4-fold less effective against B1617.1 and 2.7-fold less effective against B1617.2 than against an early strain from Wuhan, China. Still, convalescent sera containing antibodies against the Beta variant first seen in South Africa and the Gamma (P1) variant first identified in Brazil were the least able to inactivate Delta.
Data showed that the Delta variant’s affinity for ACE-2 was slightly enhanced compared with that of the Wuhan strain as well.
“Individuals previously infected by these variants may be more susceptible to reinfection by B.1.617.2,”…
The authors said that the true number of SARS-CoV-2 variants probably has been underestimated and that more variants of concern will continue to emerge. …
…”As the population develops immunity, by either natural infection or vaccination, pressure is mounting to select mutations that allow the virus to more effectively find an infectible host through increased transmissibility, or to evade the acquired immune response and cause reinfection.”…

UK Covid infections rise as Delta variant dominates (18/06/2021) | @BBCNews
… a single dose of vaccine reduces a person’s chances of catching coronavirus and needing hospital treatment by about 75%, even with Delta circulating in the UK.
And among people who had received the recommended two doses, the chances of catching and being hospitalised by coronavirus was reduced by more than 90%.
Of 806 people infected with the Delta variant who ended up hospital in England between 1 February and 14 June 2021:
527 (65%) people were unvaccinated
135 (17%) were more than 21 days after their first dose of vaccine
84 (10%) were more than 14 days after their second dose
As of 14 June, there have been 73 deaths in England of people who were confirmed as having the Delta variant and who died within 28 days of a positive test, and of these:
34 (47%) were unvaccinated
10 (14%) were more than 21 days after their first dose of vaccine
26 (36%) were more than 14 days after their second dose

Experts call for more sequencing after new ‘Delta plus’ variant identified (16/06/2021) | @Independent
… Referred to variously as the “Nepal variant”, the “Delta plus” variant or Delta AY.1, early data show this new lineage (B.1.617.2.1) allows the Covid virus to better resist antibody therapy treatments because it includes the K417N mutation – first found in the Beta variant that emerged in South Africa. …
From the data submitted by various labs across the world, we know the variant has been seen in Canada, Germany, Russia, Nepal, Switzerland, India, Poland, Portugal, Japan and the US. …
…the emergence of “Delta plus” and other new variants showed the need for regular genome sequencing to keep track of how the Covid virus is progressing.
He said the variant was “not a major concern immediately”. …

Five things we know about the Delta variant (and two things we don’t) (15/06/2021) | @gavi
Two weeks after receiving a second dose, the Pfizer-BioNTech vaccine appeared to provide 79% protection against infection with the Delta variant, compared with 92% protection against the Alpha variant…
…the number one symptom reported by app users with a confirmed infection has been headache, followed by sore throat, a runny nose, and fever. “Cough is rarer and we don’t even see loss of smell coming up in the top ten anymore…

About Variants of the Virus that Causes COVID-19? | @CDCgov
Coronavirus Variants of the Virus that Causes COVID19​​ @CDCgov




“Delta plus’ variant may trigger third COVID-19 wave in Maharashtra: Health dept (06/18/2021) | @EconomicTimes
New case of Delta Plus Covid variant detected in Bhopal (06/17/2021) | @EconomicTimes
Cause for worry’: Expert weighs in on immune escape potential of Delta plus Covid variant (06/17/2021) | @htTweets
Delta Variant Makes Up Nearly All New U.K. Coronavirus Cases (06/18/2021) | @usnews
Delta Variant Drives Huge COVID Spike in U.K. (06/17/2021) | @WebMD
WHO says delta Covid variant has now spread to 80 countries and it keeps mutating (06/16/2021) | @CNBC

What are the India, Brazil, South Africa and UK variants? (06/06/2021) | @BBCNews
… There are a few “India” variants, but one called B.1.617.2 appears to be spreading more quickly in the UK.
Surge testing is being deployed in some areas, including Bolton and Blackburn, to identify infections – but it may not be stopping the spread.
Second jabs for all over-50s (and the clinically vulnerable) in England are now being brought forward to protect more people, faster. Second doses will come eight weeks after the first, rather than 11-12 weeks.
Latest research suggests the Pfizer and AstraZeneca coronavirus vaccines are highly effective against the variant after two doses, but protection from one dose appears to be reduced. …
Coronavirus What are the India, Brazil, South Africa and UK variants @BBC






Covid-19 news: 99% of UK cases thought to be due to delta variant (06/18/2021) | @NewScientist
Covid variants: latest on the Indian, UK, South African and Brazilian variants (18/06/2021) | @TheBHF
Covid: Delta variant cases in the UK soar by 78% in one week (18/06/2021) | @Independent
COVID-19: Almost all of UK’s coronavirus cases are Delta as variant infections rise by more than 33,000 in a week (18/06/2021) | @SkyNews
Delta Variant Cases Soar in U.K. With More People Hospitalized (06/18/2021) | @bpolitics

投稿者: ワールド ソルーションズ