分类： 未分类

At least four patients have died at their homes or long-term care facilities while waiting for admission this month, said Kwak Jin, an official at the Korea Disease Control and Prevention Agency. The agency said 299 among 16,577 active patients were in serious or critical condition.

“Our hospital system isn’t going to collapse, but the crush in COVID-19 patients has significantly hampered our response,” said Choi Won Suk, an infectious disease professor at the Korea University Ansan Hospital, west of Seoul.

Choi said the government should have done more to prepare hospitals for a winter surge.

“We have patients with all kinds of serious illnesses at our ICUs and they can’t share any space with COVID-19 patients, so it’s hard,” Choi said. “It’s the same medical staff that has been fighting the virus for all these months. There’s an accumulation of fatigue.”

Critics say the government of President Moon Jae-in became complacent after swiftly containing the outbreak this spring that was centered in the southeastern city of Daegu.

The past weeks have underscored risks of putting economic concerns before public health when vaccines are at least months away. Officials had eased social distancing rules to their lowest in October, allowing high-risk venues like clubs and karaoke rooms to reopen, although experts were warning of a viral surge during winter when people spend longer hours indoors.

Jaehun Jung, a professor of preventive medicine at the Gachon University College of Medicine in Incheon, said he anticipates infections to gradually slow over the next two weeks.

The quiet streets and long lines snaking around testing stations in Seoul, which are temporarily providing free tests to anyone regardless of whether they have symptoms or clear reasons to suspect infections, demonstrate a return of public alertness following months of pandemic fatigue.

Officials are also clamping down on private social gatherings through Jan. 3, shutting down ski resorts, prohibiting hotels from selling more than half of their rooms and setting fines for restaurants if they accept groups of five or more people.

Still, lowering transmissions to the levels seen in early November — 100 to 200 a day — would be unrealistic, Jung said, anticipating the daily figure to settle around 300 to 500 cases.

The higher baseline might necessitate tightened social distancing until vaccines roll out — a dreadful outlook for low-income workers and the self-employed who drive the country’s service sector, the part of the economy the virus has damaged the most.

“The government should do whatever to secure enough supplies and move up the administration of vaccines to the earliest possible point,” Jung said.

South Korea plans to secure around 86 million doses of vaccines next year, which would be enough to cover 46 million people in a population of 51 million. The first supplies, which will be AstraZeneca vaccines produced by a local manufacturing partner, are expected to be delivered in February and March. Officials plan to complete vaccinating 60% to 70% of the population by around November.

There’s disappointment the shots aren’t coming sooner, though officials have insisted South Korea could afford a wait-and-see approach as its outbreak isn’t as dire as in America or Europe.

如果要说人类对新冠病毒疫情的斗争会留下任何遗产的话，那就是进一步拓展了办公室“白领”工作人员的工作方式。

对许多“白领”员工来说，对新冠病毒的防控努力使得他们的工作大举地从办公楼转移到了自己家中，特别是在像美国这样因特网和通讯工具既优越又普及的经济体。

一些观察家预测，居家工作或者远程工作的做法很可能持久地继续下去，并且成为现代社会的福利。居家工作的人员可以更好地控制自己的时间，让他们有更大的自由决定何时完成任务，从而在如何平衡工作、家庭生活和休闲方面给予更多的选择。

居家或者远程工作可以节约通勤时间，不会把大量的时间浪费在路上。有研究显示，尽管有担心这样做可能会牺牲与同事的社交互动，甚至居家工作的人员有被孤立和遗忘的风险；但是他们的工作效率会大大提高。

此外，总部位于瑞士、在25个国家运行的就业咨询公司“资本GES”说，减少通勤交通还有利于环境和气候的改善，并且减少了交通基础设施和成本的压力，而且降低了温室气体排放。

不过，也一些研究警告说，气候变化的福利，可能会因为家庭供暖和降温的增加而被抵消或者减少。

环保活动人士希望，新冠病毒大流行能成为重新思考人类与自然关系的巨大推动作用。他们说，新冠病毒戏剧性地提醒人们，人类不能对大自然的索取视为理所当然。

一些政府表示，经济复苏计划是这一代人启动绿色复苏的难得机会。“如果说2020年教会了我们什么，那就是：如果没有一个健康的环境，就不会有健康的人类，” 联合国环境规划署执行署长因格·安徒生这样说。

1918年首先在西班牙爆发的流感大流行，在80多年后才确定其根源是H1N1型禽流感。科学家们花了近100年的时间，才追溯到西班牙流感病毒始源于美国堪萨斯州哈斯克尔郡，最早在1916年就出现了。

Last week, a new SARS-CoV-2 variant was identified in parts of London and southeast England where Covid-19 cases were surging. According to the Covid-19 Genomics UK Consortium (COG-UK Consortium) that sequenced the genome data of the virus and identified it, the new variant has been spreading “rapidly” over the last four weeks and has now been detected in other parts of the United Kingdom.

UK Prime Minister Boris Johnson recently said the new variant of SARS-CoV-2 could be up to 70 per cent more transmissible than other variants. This prompted several countries to impose limited or complete travel bans for the UK.

The new variant came to light in early December because of the UK’s phenomenal genomic surveillance system for Covid-19. After looking at genomic analysis and epidemiological evidence of increased transmission, the Public Health England (PHE) concluded that “the new variant was showing signs of increased transmissibility.”

The European Centre for Disease Prevention and Control (CDC), World Health Organisation (WHO), the US CDC, and the Public Health England technical briefing all clarify that current evidence only supports increased transmissibility and there is no evidence about increased or decreased disease severity, impact on reinfections, therapeutics or vaccines.

EXPLAINING THE BASIS OF MUTATION

Imagine SARS-CoV-2 as a tiny bubble with tiny clubs projecting out from its surface. The virus comprises different types of proteins and genetic code called RNA (ribonucleic acid) enveloped by a layer of fat (lipids from the bubble). The tiny clubs are called S proteins (spike protein) and they’re a very important part of the virus. The S protein attaches to a specific receptor on host cells (called ACE-2), and if the fit is right, the virus can infect the cells. If the S protein is a partial fit, the virus may not be able to infect the cells as easily. The better the fit between the S protein and the receptor, the better the virus can infect the host cell.

The RNA genetic code consists of a series of letters and this represents the genetic blueprint to make all the coronavirus’s proteins, including the S protein. The RNA blueprint determines which protein building blocks are present. These building blocks are called amino acids. A change in the virus’s RNA may cause a change in its amino acids which can result in a change in the S protein.

When the virus infects a host cell, it tricks the host cell into making copies of viral RNA and proteins in a process called replication. During replication inside host cells, viral RNA needs to be copied thousands of times to make RNA for offspring viruses. During this process, a few errors may occur resulting in a different RNA genetic code. These errors are called mutations and the coronavirus mutates regularly, acquiring about one new mutation in its genome every two weeks.

Many mutations do not result in any changes in the amino acids that make proteins. Some mutations do result in a change in the amino acids but often have no functional impact on the virus’s proteins. Occasionally, a mutation may occur that results in a change in a protein’s function. For example, a mutation may result in a new amino acid that makes a new S protein which may fit better with the host cell ACE-2 receptor. This may create a virus that can infect cells better and pass more easily from one host to another.

Changes in proteins may also result in a longer duration of infection or a more severe infection. The opposite is also true; some mutations may result in a virus that is less transmissible and causes less severe infection.

Changes in the S protein can also impact immunity against the virus. Our immune response against the virus targets the S protein. If the coronavirus has a new S protein, then it may be able to escape an immune response against the old S protein. A coronavirus with a different S protein might cause reinfections in people who have recovered from Covid-19 and vaccines targeting the old S protein might become less effective.

When a set of specific mutations occur together, it can result in a new variant of the same coronavirus. Sometimes, a variant may have many mutations and some of these mutations may give the virus a functional advantage.

THE UK VARIANT

In early December, scientists in the United Kingdom studying Covid-19 observed a sudden spike in cases in parts of the country. They got concerned when genomic analysis revealed a new SARS-CoV-2 variant with many mutations occurring together. Concern caused alarm when they realised that over half of the new cases in that area were caused by the new variant. This variant has been named SARS-CoV-2 VOC 202012/01 (the first ‘Variant of Concern’ in December 2020) and is also called B.1.1.7.

The names VOC 202012/01, B.1.1.7 and UK variant are used interchangeably in the media and refer to the same SARS-CoV-2 variant. The UK variant is characterised by 23 mutations, an unusually large number of mutations, and several of these mutations have resulted in changes in the S protein.

Scientists are particularly concerned about mutations changing the amino acids in the spike protein in a way that changes the S protein’s function. N501Y (a change at position 501 of the spike protein) and Spike deletion 69/70del (a double deletion at position 69 and 70 of the spike protein) are thought to increase transmissibility and impact molecular tests for Covid-19; studies are underway to determine if there’s any impact on immunity.

PROBABLE IMPLICATIONS OF THESE MUTATIONS

Ability to spread more easily or quickly between humans:

These mutations have caused small changes in the S protein and it is thought this has resulted in a variant that is more transmissible.

While there is some uncertainty about the exact increase in transmissibility, experts at the Public Health England are confident that there is a significant increase in the variant’s capability to pass on from one person to another. This is worrying because a more transmissible variant may cause many new Covid-19 infections, more hospitalisations and deaths.

Ability to cause milder or more severe infections:

Currently, there is no conclusive evidence that the UK variant causes more severe infections or has a higher fatality rate but there is also no evidence that it does not do so. More evidence is needed to make any claims about the impact on severity. Most healthcare systems across the world are already at peak capacity and any sudden spike in new cases would be a matter of serious concern.

Ability to evade immunity (reinfections and vaccines):

The S protein enables the coronavirus to infect host cells and therefore, natural immunity following Covid-19 and vaccines both target this S protein.

The S protein is an antigen, which is a protein that triggers an immune response. Antigens have different parts that the immune system can recognise; these are called epitopes or antigenic determinants. A mutation may change just one antigenic determinant on the S protein but there are many others that are still the same and therefore, the immune system can still recognise the S protein. The immunity developed following recovery from Covid-19 or after complete vaccination targets multiple antigenic determinants on the S protein, so even if one part of the S protein changes, there will still be some protection against the new variant.

Currently, there is no evidence that those who have recovered from Covid-19 in the past are at increased risk of reinfections due to this new variant. The Menachery Lab tweeted out data that suggests patients who have recovered from Covid-19 in the past have antibodies that may protect against variants with N501Y.

While this is good news, this data has not been peer-reviewed outside of Twitter and the UK variant has other spike mutations that could have some impact on reinfections. Again, more evidence is needed to make any claims about reinfections.

Everyone should be reassured that existing vaccines target the entire S protein and early evidence indicated post-vaccination immunity is robust. So, we have reasons to expect that existing Covid-19 vaccines will offer protection against the UK variant. The possibility of a modest decrease in the efficacy of Covid-19 vaccines is something that is being investigated vigorously by scientists in the UK.

Some authorities have issued false reassurances that this variant is not causing more severe infections and that it will have no impact on vaccines. Others have caused alarm and panic by suggesting the UK variant is a super mutant virus. Both positions are entirely unsupported by available evidence.

THE ROAD AHEAD

In response to news of the UK variant, many countries, including India, have imposed travel restrictions. These are sensible first steps but it’s likely that the new variant is already spreading undetected in India. Detecting new mutations requires advanced genetic tests and the UK is the world leader in this area of science.

The United Kingdom performs more such tests in a single month than most countries have performed in total since the pandemic started. The UK was looking for variants and it found one of concern. Other countries, India included, need to step up surveillance systems. The Indian Council of Medical Research has started looking for the variant in India.

We should be concerned about the more transmissible UK variant, but we should also be concerned about human behaviour that increases transmission. Each and everyone of us has a role to play in the battle against the virus.

虽然欧洲各国在圣诞假期期间严阵以待新冠疫情，但部份国家确诊数目仍然上升；欧盟民众将自本周日起开始接种新冠疫苗。

意大利接收的首批9750剂新冠疫苗周五运抵境内。运载该批疫苗的货车由北部边境口岸入境后，在宪兵护送下开往罗马的国家传染病研究所医院，然后向各大区进行分发。未来几周内，每周将有约30万剂疫苗运抵意大利。

按照欧盟统一计划，意大利接种辉瑞与德国BioNtech合研的新冠疫苗，将在星期日展开，医护人员获优先接种。

法国卫生部周五晚间通报，法国首批疫苗接种者将是巴黎以东的塞弗昂老人院的人员。

西班牙多个大区的确诊病例也在持续升高，其中巴利阿里大区14天内每10万居民有462.8个病例，较一周前增加了40%。

英国单日新冠病毒确诊稍有下降，由平均每天过3万9000例减少至3万2725例。不过在英国发现的传播力更强的变种新冠病毒在其他地方陆继出现，包括爱尔兰及日本。