Latest coronavirus news as of 1pm 3 May
People hospitalised with covid-19 may lose 10 IQ points, equivalent to the natural cognitive decline that occurs between 50 and 70 years old
Covid-19 can cause lasting cognitive and mental health issues, including brain fog, fatigue and even post-traumatic stress disorder. To better understand the scale of the problem, researchers at the University of Cambridge analysed 46 people who were hospitalised due to the infection between March and July 2020.
The participants underwent cognitive tests on average six months after their initial illness. These results were compared against those of more than 66,000 people from the general population.
Those hospitalised with covid-19 scored worse on verbal analogical reasoning tests, which assess an individual’s ability to recognise relationships between ideas and think methodically.
They also recorded slower processing speeds. Previous studies suggest glucose is less efficiently used by the part of the brain responsible for attention, complex problem-solving and working memory after covid-19.
Scores and reaction speeds improved over time, however, any recovery was gradual at best, according to the researchers.
This cognitive impairment probably has multiple causes, including inadequate blood supply to the brain, blood vessel blockage and microscopic bleeds caused by SARS-CoV-2 virus, as well as damage triggered by an overactive immune system, they added.
“Around 40,000 people have been through intensive care with covid-19 in England alone and many more will have been very sick, but not admitted to hospital,” Adam Hampshire at Imperial College London said in a statement.
“This means there is a large number of people out there still experiencing problems with cognition many months later.”
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The biological mechanism behind a rare and severe covid-19 response seen in some children may have been uncovered by researchers at the Murdoch Children’s Research Institute in Melbourne, Australia.
Doctors have so far been unable to identify why some children develop multisystem inflammatory syndrome (MIS) in response to covid-19, which can cause symptoms such as fever, abdominal pain and heart disease.
After analysing the blood of 33 children with MIS, the researchers identified 85 proteins specific to the condition, potentially aiding diagnosis and opening the door to new treatments.
Covid-19 may worsen asthma in children, according to a study of more than 61,000 people aged two to 17 with the respiratory condition in the US. The 7700 participants who tested positive for covid-19 went on to have more asthma-related hospitalisations, emergency inhaler use and steroid treatments in the six months post-infection, compared with the participants without a confirmed covid-19 infection.
How covid-19 affects people with asthma is somewhat muddled. In November 2020, a study found people with asthma may be less likely to develop covid-19 complications, potentially due to their steroid use or reduced exposure via shielding.
Essential information about coronavirus
Where did coronavirus come from? And other covid-19 questions answered
What is covid-19?
Covid-19 vaccines: Everything you need to know about the leading shots
Long covid: Do I have it, how long will it last and can we treat it?
What’s the fairest way to share covid-19 vaccines around the world?
Covid-19: The story of a pandemic
What to read, watch and listen to about coronavirus
New Scientist Weekly features updates and analysis on the latest developments in the covid-19 pandemic. Our podcast sees expert journalists from the magazine discuss the biggest science stories to hit the headlines each week – from technology and space, to health and the environment.
The Jump is a BBC Radio 4 series exploring how viruses can cross from animals into humans to cause pandemics. The first episode examines the origins of the covid-19 pandemic.
Why Is Covid Killing People of Colour? is a BBC documentary, which investigates what the high covid-19 death rates in ethnic minority patients reveal about health inequality in the UK.
Panorama: The Race for a Vaccine is a BBC documentary about the inside story of the development of the Oxford/AstraZeneca vaccine against covid-19.
Race Against the Virus: Hunt for a Vaccine is a Channel 4 documentary which tells the story of the coronavirus pandemic through the eyes of the scientists on the frontline.
The New York Times is assessing the progress in development of potential drug treatments for covid-19, and ranking them for effectiveness and safety.
Humans of COVID-19 is a project highlighting the experiences of key workers on the frontline in the fight against coronavirus in the UK, through social media.
Belly Mujinga: Searching for the Truth is a BBC Panorama investigation of the death of transport worker Belly Mujinga from covid-19, following reports she had been coughed and spat on by a customer at London’s Victoria Station.
Coronavirus, Explained on Netflix is a short documentary series examining the coronavirus pandemic, the efforts to fight it and ways to manage its mental health toll.
Stopping the Next Pandemic: How Covid-19 Can Help Us Save Humanity by Debora Mackenzie is about how the pandemic happened and why it will happen again if we don’t do things differently in future.
The Rules of Contagion is about the new science of contagion and the surprising ways it shapes our lives and behaviour. The author, Adam Kucharski, is an epidemiologist at the London School of Hygiene and Tropical Medicine, UK, and in the book he examines how diseases spread and why they stop.
Infections have risen considerably, driven by two new omicron sublineages
South Africa may be at the start of its fifth covid-19 wave, just three months after exiting its fourth wave.
The country’s new recorded infections have been rising since mid-April. On 18 April, 1354 cases were recorded as a seven-day average, more than doubling to 3251 on 25 April.
A growing number of the infections are sublineages of the omicron variant, called BA.4 and BA.5, Helen Rees at the University of the Witwatersrand in Johannesburg said at a news conference on 28 April.
These sublineages accounted for more than half of South Africa’s new infections in the first week of April and are more transmissible than the previously dominant BA.2 sublineage, according to a paper by Tulio de Oliveira at Stellenbosch University, South Africa, and his colleagues.
Covid-19 hospitalisations are also picking up, however, intensive care admissions and deaths remain broadly stable, South Africa’s health minister Joe Phaahla said at a briefing on 29 April.
South Africa’s seven-day average of daily deaths rose from 12 on 18 April to 22 on 25 April.
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Moderna has filed for authorisation of a low-dose covid-19 vaccine for children aged 6 months to under 6 years in the US. Two doses of the vaccine were 51 per cent effective at preventing omicron infections in children under 2 and 37 per cent effective in 2- to 5-year-olds. The Pfizer/BioNTech covid-19 vaccine is only approved for 5- to 11-year-olds in the US.
Some of the genetic variants that predispose people to severe covid-19 also raise their risk of other conditions, such as heart disease, blood clots and type 2 diabetes. But genetic variants that cause certain auto-immune conditions, where the immune system mistakenly attacks the body’s cells, such as rheumatoid arthritis, are linked with a lower risk of severe covid-19, according to a large study of more than 650,000 people in the US. The findings may help in the development of future covid-19 treatments, according to the authors.
Denmark has temporarily suspended covid-19 vaccinations amid high levels of immunisation, a drop in cases and stabilising hospitalisation rates
The Danish government will no longer send out covid-19 vaccination invitations after 15 May, however, an immunisation programme is expected to resume in the autumn.
More than four in five (82 per cent) people in Denmark’s 5.8-million-strong population are fully vaccinated, defined as having two jabs.
The country reported 1549 covid-19 cases on 26 April, an average calculated from the last seven days. Fewer than 1000 people have been in hospital with covid-19 since early April.
On 1 February, Denmark was the first country in the European Union to scrap all of its covid-19 restrictions, announcing SARS-CoV-2 virus was no longer a critical threat.
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Reduced testing across many countries means the world is “increasingly blind to patterns of transmission and evolution” of covid-19, according to the World Health Organization (WHO).
“As many countries reduce testing, WHO is receiving less and less information about transmission and sequencing,” Tedros Adhanom Ghebreyesus, the WHO’s director-general, said in a press conference on 26 April.
Covid-19 was the sixth leading cause of death in England in March, accounting for 4.3 per cent of all fatalities, according to the Office for National Statistics. In February, covid-19 was the third leading cause of death in England, accounting for 5.6 per cent of all fatalities.
Pfizer and its partner BioNTech have applied for authorisation of their booster shot for 5 to 11 year olds in the US. Just 28 per cent of this age group are fully vaccinated, according to the US Centers for Disease Control and Prevention, after two doses were made available to 5 to 11 year olds last October.
This follows a small study of 30 participants that revealed the booster shot increased neutralising antibodies against omicron 36-fold.
People hospitalised with the supposedly milder omicron variant require similar levels of respiratory support and intensive care as those infected with delta
Heba Mostafa at John Hopkins University in the US and her colleagues studied more than 2000 people who tested positive for covid-19 between November and December 2021. The team recorded which variant the participants were infected with and their clinical outcomes.
Results reveal 73 per cent of the participants who were hospitalised with delta needed extra oxygen, while 25 per cent required intensive care.
Similarly, 67 per cent of those who were hospitalised with omicron required extra oxygen and 17 per cent needed intensive care.
Nevertheless, the participants who were infected with omicron were less likely to be hospitalised in the first place, regardless of their vaccine status. Only 3 per cent of the participants infected with omicron were admitted to hospital, compared with 13 per cent of those with delta.
“It’s true that patients with omicron were significantly less likely to be admitted to the hospital than patients with delta,” Mostafa said in a statement. “But omicron patients who did need hospitalisation faced a risk of severe disease comparable to those hospitalised with delta.
“For many people, it is not a mild infection at all.”
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Singapore removed nearly all of its remaining covid-19 restrictions today. Mask wearing indoors and on public transport are some of the only remaining curbs, with officials dropping limits on group sizes, social distancing guidelines and restrictions on the number of people who can work in an office at any one time.
Nearly two-thirds of people who were restricted from visiting relatives while they were hospitalised with covid-19 may have developed a stress-related disorder.
Researchers at the University of Colorado Denver surveyed 330 relatives three months after a family member was admitted to intensive care with covid-19 between February and July 2020.
Just under two-fifths (64 per cent) of the relatives scored high on tests that measure symptoms of post-traumatic stress disorder. This is more than double pre-pandemic levels, when relatives were similarly surveyed after a loved one was admitted to intensive care for non-covid-19 reasons.
“Our findings suggest that visitation restrictions may have inadvertently contributed to a secondary public health crisis, an epidemic of stress-related disorders mong family members of ICU patients,” Timothy Amass said in a statement.
Only 29 per cent of people who were hospitalised with covid-19 in the UK feel fully recovered one year later
Rachael Evans at the University of Leicester, UK, and her colleagues looked at 2320 people in the UK who were discharged from hospital, after being admitted with covid-19, between March 2020 and April 2021. All the participants were assessed five months later, while a third (33 per cent) were also assessed one year post-discharge.
Symptoms – most commonly fatigue, muscle pain, poor sleep and breathlessness – persisted in 74 per cent of the participants five months later, decreasing slightly to 71 per cent at one year.
“The limited recovery from five months to one year after hospitalisation in our study across symptoms, mental health, exercise capacity, organ impairment, and quality-of-life is striking,” Evans said in a statement.
While severe covid-19 is more common among males, the female participants were 32 per cent less likely to feel fully recovered one year on. Obesity and having had mechanical ventilation were linked to the participants being 50 and 58 per cent less likely to feel fully recovered, respectively.
“Given that more than 750,000 people have been hospitalised in the UK with covid-19 over the past two years, it is clear from our research that the legacy of this disease is going to be huge,” said Evans.
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Unvaccinated people could raise the covid-19 risk among vaccinated people, even when immunisation rates are high. David Fisman at the University of Toronto and his colleagues simulated how different levels of population mixing affect the spread of SARS-CoV-2 virus.
New infections were high when the simulated groups of vaccinated and unvaccinated people mixed. “We found that the choices made by people who forgo vaccination contribute disproportionately to risk among those who do get vaccinated,” Fisman said in a statement.
Shanghai in China reported a record 51 covid-19 deaths and more than 19,000 new cases today, its highest daily total since the pandemic began. Shanghai’s over 25-million-strong population remains locked down as authorities try to maintain their zero covid policy.
Cases are also surging across the rest of China, with nearly 22,000 new reported cases on 24 April, according to its national health ministry. Mass testing is being rolled out in Beijing after 26 new cases were identified.
About 5 million new covid-19 cases were reported worldwide between 11 and 17 April, a 24 per cent reduction on the previous week
The number of official covid-19 cases is continuing to decline across the globe, according to a report by the World Health Organization.
This reduction occurred across all of the six regions monitored by the WHO, but is most pronounced in the Western Pacific, where reported cases declined by 28 per cent week-on-week.
This is followed by Eastern Mediterranean (26 per cent), Europe (25 per cent), South East Asia (16 per cent), Africa (7 per cent) and the Americas (2 per cent).
Reported deaths similarly declined globally by 12 per cent week-on-week.
The WHO has stressed these figures should be interpreted with caution. Changes in how countries are testing for SARS-CoV-2 virus may mean fewer swabs are being carried out, leading to a lower number of cases being detected.
For example, England has scrapped free universal testing, while rules around free tests are also tightening in Wales and Scotland. Covid-19 tests are more widely available in Northern Ireland.
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Exposure to air pollution may increase your risk of catching SARS-CoV-2 virus. Zhebin Yu at the Karolinska Institute in Stockholm, Sweden, and his colleagues looked at 425 people, average age 25, who tested positive between May 2020 and March 2021.
Levels of airborne particulate matter and black carbon, also known as soot, around the participants’ homes were higher in the days leading up to their positive test, compared with later control days.
A single dose of AstraZeneca’s dual-antibody treatment Evusheld could reduce the risk of symptomatic covid-19 by 83 per cent over six months, compared with a placebo.
The study was made up of more than 5000 adults, all of whom were less likely to respond to a covid-19 vaccine or faced greater SARS-CoV-2 virus exposure.
No severe covid-19 cases or covid-19-related deaths occurred in the Evusheld group. In the placebo group, five cases of severe or critical disease, seven hospitalisations and two covid-19-related deaths had occurred by the six-month follow-up.
China’s biggest city has reported seven covid-19 deaths, the first official fatalities amid its ongoing omicron outbreak
Shanghai is the epicentre of the largest covid-19 outbreak in China since the SARS-CoV-2 virus emerged at the end of 2019, with its surge in cases driven by the more transmissible omicron variant.
Despite relatively high case numbers, only seven people are known to have died with the infection amid the ongoing outbreak as of today, according to China’s health officials.
China’s largest city has been in a widespread lockdown since 6 April. The restrictions were initially intended to take place in two stages, affecting Shanghai’s eastern districts for five days, followed by an additional five days of lockdown in its western districts. Lockdown was later extended to cover the city’s entire 26-million-strong population.
Case numbers appear to be falling, prompting Shanghai officials to report they are preparing to ease the lockdown.
On 18 April, 19,831 new asymptomatic infections were reported, down from 21,592 on 16 April. New symptomatic infections stood at 2417 on 18 April, down from 3238 the previous day.
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Babies born during the covid-19 pandemic may be slower to speak than those born before the outbreak emerged, according to research published by Brown University and LENA, a US non-profit organisation.
Data taken from LENA’s “talk pedometer”, a wearable device that tracks what a child hears throughout the day and the infant’s own vocalisations, show a large drop in so-called verbal function in children aged between 12 and 16 months who were born after July 2020, compared with those born before 2019.
These results reinforce earlier studies that suggest the pandemic has negatively impacted children’s brain development.
The US Centres for Disease Control and Prevention (CDC) has removed all remaining countries from its highest coronavirus travel risk category. The CDC’s “Level 4: Special Circumstances/Do Not Travel” designation previously urged people to avoid all non-essential travel to these destinations.
In a statement, the CDC said Level 4 would now be reserved for countries with special circumstances, including rapidly escalating case numbers or the emergence of a new variant of concern. The UK, France and Germany are among countries that remain at the CDC’s “Level 3 Covid-19: High” warning.
The UK has approved a sixth covid-19 vaccine, which contains a whole inactivated form of the SARS-CoV-2 virus and can be stored in a fridge
A vaccine that contains a whole inactivated form of SARS-CoV-2 virus is the sixth covid-19 vaccine to be approved by the UK’s Medicines and Healthcare products Regulatory Agency (MHRA).
In March, Bahrain was the first country in the world to approve the vaccine for emergency use. Now, the UK is the first in Europe to sign off on the jab, which can be stored for up to a year in a standard fridge.
The mRNA vaccines from Moderna and Pfizer/BioNTech have to be stored at no more than -20°C, for a maximum of six months. Once thawed, the Moderna jab lasts up to 30 days in a standard fridge, while the Pfizer/BioNTech vaccine can be kept for just five days.
The MHRA approval follows promising results from a study completed in October last year. Two doses of the Valneva jab, administered 28 days apart, led to about 40 per cent higher neutralising antibody levels than the Oxford/AstraZeneca vaccine, which can similarly be stored at higher temperatures.
The study only compared the two vaccines against each other, not against people who did not receive any jab.
The rate of covid-19 infections was “similar” between the two groups, with no severe disease occurring among any of the study’s 4012 participants.
“The independent Commission on Human Medicines [CHM] and its COVID-19 Expert Working Group has carefully considered the available evidence [and] are pleased to say that we have advised that the benefit risk balance is positive,” Munir Piromohamed at CHM said in a statement.
“The vaccine is approved for use in people aged 18 to 50 years, with the first and second doses to be taken at least 28 days apart.”
This comes as Pfizer’s chief executive said the firm could develop a covid-19 vaccine that protects against all known variants by the end of the year.
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People with an increased risk of heart disease are up to six times more likely to die from covid-19.
The study, which will be presented at the European Congress of Clinical Microbiology and Infectious diseases later this month, found people with a more than 10 per cent chance of having a stroke or heart attack in the next 10 years are nearly three times more likely to be admitted to intensive care with covid-19 and six times more likely to die of its complications.
This is compared with people with a less than 10 per cent risk of developing heart disease, calculated according to factors like their body mass index, smoking status and blood pressure.
The US has extended its covid-19 public health emergency status, which was initially declared in January 2020 and has been renewed every quarter since. It was due to expire on 16 April.
The renewal allows people in the US access to free covid-19 tests, vaccines and treatments for at least another three months.
More than 500 million covid-19 cases have been recorded globally since the outbreak emerged, but the true number is probably far higher
According to Johns Hopkins University’s case tracker, more than 500,900,000 covid-19 cases have been reported worldwide. The World Health Organisation (WHO) tracker, which updates daily, is just shy of this grim milestone, reporting 497,960,492 cases as of 12 April.
Experts have warned a lack of testing infrastructure worldwide means the global case number is probably much higher than is being reported, particularly in poorer countries. A WHO analysis estimates Africa’s true case number is 100 times higher than that which is being reported.
And unaccounted cases are expected to become more common as countries scale back their test capacity, for example in the UK.
The number of new worldwide cases appears to have been falling in recent weeks, with the daily case rate 41 per cent lower than it was two weeks ago, according to Johns Hopkins University. Reduced testing and a subsequent underreporting of cases probably contributed to this apparent fall in cases.
Tedros Adhanom Ghebreyesus at the WHO has warned we are still in an “acute phase of the pandemic”, as the more transmissible omicron variant and its sublineages spread across the world.
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An analysis of Israel’s vaccine booster campaign has revealed the timing of booster roll-outs is crucial to preventing a surge in cases, particularly when infections are growing exponentially.
The researchers, from Technion-Israel Institute of Technology in Haifa, Israel, also found vaccinating younger age groups, who are less likely to become seriously ill with covid-19, is key to preventing transmission.
If Israel hadn’t initiated its booster campaign, officials would have “needed to apply extensive non-pharmaceutical interventions to prevent a destructive epidemic wave”, the analysis concluded.
The number of reported cases in England has fallen 26 per cent week-on-week, dropping from 51,253 on 6 April to 37,819 on 12 April. These figures are expected to be considerably less useful for tracking the pandemic’s progress since England scrapped free universal testing on 1 April.
Doctors are investigating what could be causing a surge in liver inflammation, or hepatitis, in children in the UK, after 74 cases have been reported so far this year.
Hepatitis can be caused by a range of pathogens, including viruses. Officials are looking at whether the rise in cases may be a rare delayed reaction to covid-19. Graham Cooke at Imperial College London has said exposure to a circulating virus after the lifting of restrictions could be behind the surge.
Heart inflammation may be no more likely after a covid-19 vaccine than any other jab
In rare cases, the mRNA-based Pfizer/BioNTech and Moderna covid-19 vaccines in particular have been linked to heart inflammation. The risk is higher among younger people, which contributed to the UK’s delayed decision to roll-out covid-19 vaccines to 5-to-11 year olds.
Now, an analysis of 22 studies with hundreds of millions of vaccine doses administered between them shows heart inflammation is no more common after a covid-19 jab than it is after vaccines that protect against some other infections, such as smallpox or influenza – and in some cases the risk may be lower.
The study, published in The Lancet Respiratory Medicine, found 18 cases of heart inflammation occur per 1 million covid-19 vaccine doses, compared with 56 cases per 1 million doses of non-covid vaccinations. The rate of heart inflammation was even found to be “significantly higher” after a smallpox jab than a covid-19 vaccine.
Aligning with past research, the study found men and people under 30 were more likely to develop heart inflammation. The risk was also higher in those who had an mRNA vaccine as opposed to a jab based on different technology, such as the Oxford/AstraZeneca or Janssen vaccines, and after a second dose of any covid-19 jab.
“Our research suggests that the overall risk of myopericarditis [heart inflammation] appears to be no different for this newly approved group of vaccines against COVID- 19, compared to vaccines against other diseases,” study author Dr. Kollengode Ramanathan at National University Hospital, Singapore, said in a statement.
“The risk of such rare events should be balanced against the risk of myopericarditis from infection and these findings should bolster public confidence in the safety of COVID-19 vaccinations.”
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The World Health Organisation (WHO) is tracking two new sublineages of the omicron variant to determine if they are more transmissible, virulent or better able to evade past immunity.
Dubbed BA.4 and BA.5, only a few dozen cases of the sublineages have been reported globally, however the WHO is tracking them due to their “additional mutations that need to be further studied to understand their impact on immune escape potential”.
BA.4 has been identified in South Africa, Denmark, Botswana, Scotland and England, the UK’s Health Security Agency said last week. BA.5 had exclusively been found in South Africa, however, Botswana’s health ministry reported cases of both BA.4 and BA.5 yesterday.
People in the UK are more worried about their finances than catching covid-19, despite an estimated one in 13 people being infected across England, Wales and Scotland, while one in 16 are thought to have covid-19 in Northern Ireland.
A team from University College London surveyed 28,495 people between 21 March and 27 March. One third (33 per cent) of the participants said they are concerned about catching covid-19, down from 40 per cent in January.
In the light of the UK’s cost of living crisis, 38 per cent said they are worried about their finances, up from 32 per cent in January.
The survey also found that 49 per cent of people feel in control of their mental health, down from 54 per cent six months ago, and the number of people reporting anxiety or depression symptoms is at its highest level in 11 months.
“These findings could suggest that our return to more ‘normal’ living has not had all the mental health benefits that people necessarily expected.” Daisy Fancourt at UCL told Sky News.
An estimated one in 13 people in England, Wales and Scotland were infected at the start of April
Covid-19 infections remain high, with an estimated one in 16 people having the infection in Northern Ireland and one in 13 people in the rest of the UK over the first weekend of April, according to an Office for National Statistics (ONS) survey.
This equates to just under 4.9 million people being infected across the UK – 25,000 fewer cases than the previous week’s record high.
“While infections remain high, there are early signs in our latest data that they may no longer be increasing in some parts of the UK,” Sarah Crofts at ONS said in a statement.
“Across English regions, there is a mixed picture in trends and we have seen a welcome decrease in Scotland. However, rates in Wales continue to rise and the trend in Northern Ireland is uncertain.
“It is too early to say if infections have peaked in England and Scotland.”
The ONS survey swabs thousands of random people for SARS-CoV-2 virus, regardless of whether they have symptoms, and is unaffected by the end of free universal testing in England.
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The rise in covid-19 cases in the US is concerning but not unexpected, according to the country’s chief medical adviser Anthony Fauci. The US recorded 35,243 new cases on 9 April.
The more transmissible omicron BA.2 sublineage is thought to be driving the rise in infections, along with the easing of restrictions.
Shanghai will start loosening lockdown restrictions in some regions from today, according to city officials. This is despite the city reporting more than 26,000 new cases in the past 24 hours, a new record.
China’s largest city was initially placed in a two-stage 10-day lockdown, affecting its eastern districts for five days, followed by an additional five days of restrictions in its western districts. This was then extended to cover all of Shanghai’s 25-million-strong population.
Officials now plan to lift some restrictions in areas that have not had any positive cases for two consecutive weeks.
Omicron’s symptom duration is shorter than delta’s among people who have had a booster vaccine
Cristina Menni at King’s College London and her colleagues analysed more than 63,000 people who tested positive for SARS-CoV-2 virus between June 2021 and January 2022. The participants, who had all received at least two doses of any covid-19 vaccine, self-reported their positive test result and symptoms via the Zoe COVID app.
From June to November 2021, when delta was the dominant variant in the UK, covid-19 symptoms lasted on average 7.7 days among the participants who were triple jabbed. This is compared with an average 4.4-day symptom duration when omicron was dominant, defined as the end of December 2021 to mid-January 2022, when the study completed.
Omicron has long been known to be less virulent than past covid-19 variants. Its mild symptoms may also differ from delta’s.
Fewer than one in five (17 per cent) of the participants who caught covid-19 when omicron was dominant reported a loss of smell, compared with over half (53 per cent) of those who probably had delta.
Those who probably caught omicron were more likely to report a sore throat and hoarse voice than those with delta, however, the latter variant was more strongly linked to brain fog, headache and fever.
“It is a lesson that we need to be far more flexible in thinking what the virus is and how it is going to present than we have been, certainly in the UK,” Tim Spector at King’s College London told The Guardian.
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More than two-thirds of people living in Africa have been infected with SARS-CoV-2 virus since the pandemic began – 97 times more than the continent’s officially reported cases, according to a World Health Organization (WHO) study.
WHO researchers analysed 151 previous studies on the proportion of people in Africa with covid-19 antibodies. They estimate about 800 million people had been infected by September 2021, but just 8.2 million cases were reported.
Shanghai reported a record 21,000 covid-19 cases today. The city’s lockdown was recently extended to cover all of its 25-million-strong population. Officials have not indicated when the lockdown may end.
The risk of a potentially life-threatening lung clot increases 33-fold within a month of being infected
Ioannis Katsoularis and his colleagues at Umeå University in Sweden tracked more than 1 million people in Sweden who tested positive for SARS-CoV-2 virus between February 2020 and May 2021. They compared the health outcomes of this group with 4 million people, also living in Sweden, who had not had a positive covid-19 test.
Regardless of the severity of a person’s covid-19 symptoms, the risk of deep vein thrombosis (DVT) within 30 days of infection increased five-fold, persisting at this level for three months. DVT is a blood clot in a vein, usually in the leg, which can break off and travel to the lungs. This can cause a pulmonary embolism, which blocks blood flow to the lungs.
For pulmonary embolism specifically, a positive covid-19 test was found to raise the risk of the condition 33-fold, persisting at this level for six months, compared with the participants who never tested positive for SARS-CoV-2 virus.
The clot risk was highest among participants with severe covid-19, however, even those with mild covid-19 symptoms were three times more at risk of DVT and seven times more at risk of a pulmonary embolism.
Being infected during the pandemic’s first wave, in early 2020, was also linked to a raised risk of clots. The roll-out of vaccines and improved covid-19 treatments later in the pandemic probably protected against clots, according to the researchers.
“Despite the potential for new variants of concern, most governments are removing restrictions and shifting their focus to determining how best to live with covid,” Frederick Ho at the University of Glasgow, told The Guardian. “This study reminds us of the need to remain vigilant to the complications associated with even mild Sars-CoV-2 infection”.
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An estimated 1.7 million people in the UK, about 2.7 per cent of the population, have long covid, according to an Office for National Statistics (ONS) survey. The survey participants self-reported any long covid symptoms, defined as those that persist for more than four weeks after a suspected SARS-CoV-2 virus infection and cannot be explained by something else.
Of these, 1.1 million said their long covid symptoms adversely affect their day-to-day activities, with 322,000 saying their ability to perform daily activities has been “limited by a lot”.
Males in the Bangladeshi ethnic group have the highest covid-19 mortality rate in England, according to ONS data. These males are 2.7 times more likely to die from covid-19 than their white British counterparts. Among females, people in the Pakistani ethnic group are 2.5 times more likely to die from covid-19 than their white British counterparts. Disparities in mortality rates between different ethnic groups may be down to varying vaccine uptake.
Cases are declining among younger age groups but remain high overall
One in 16 people in England is thought to have covid-19, the highest prevalence recorded by Imperial College London’s surveillance study React since it started in May 2020.
According to the Office for National Statistics, which uses a different method for estimating SARS-CoV-2 infection rates, one in 16 people in England had covid-19 on the week ending 19 March, rising to one in 13 seven days later.
In the latest React study, swabs collected from a random sample of almost 110,000 people suggest 6.37 per cent of England’s population tested positive for the SARS-CoV-2 virus between 8 and 31 March – more than double the one in 35 people who were thought to have the infection the previous month.
The more-transmissible omicron BA.2 sublineage made up an estimated 94.7 per cent of the March cases, up from just 0.8 per cent in January. A very small number of the infections were recombinants of the sublineages BA.1 and BA.2, including five incidences of the recombinant XE. Early tests suggest XE may be around 10 per cent more transmissible than BA.2, according to the World Health Organization.
Despite infections rising across all age groups, incidences appear to be declining in people aged 5 to 17 and plateauing among those aged 18 to 54.
This is not the case for people aged 55 and over, however, where infections are rising. On 31 March, an estimated 8.31 per cent of people in this age group would have tested positive – nearly 20 times the average prevalence since the React programme began.
“These trends are concerning since when a very high number of people are infected, this may lead to more people becoming seriously ill and needing to go to hospital.” Professor Paul Elliott, director of the REACT programme, said in a statement.
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Shanghai’s lockdown has been extended to cover all of the city’s 25-million-strong population. China’s largest city was initially placed in a two-stage 10-day lockdown, affecting its eastern districts for five days, followed by an additional five days of restrictions in its western districts.
On 4 April, the city reported 13,086 new asymptomatic cases, after testing 25 million people in 24 hours. This is a relatively low number of infections compared with other nations, however, China is imposing strict restrictions as it pursues a “zero covid” policy.
A second booster dose of the Pfizer/BioNTech vaccine provides some protection against severe illness among people over 60 who are infected with omicron BA.1, according to a study of more than 1 million people in Israel. Severe illness aside, protection against infection with the SARS-CoV-2 virus itself waned after four weeks.
The symptom list has been expanded days after officials ended free universal testing in England
For most of the pandemic, the NHS in England has only recognised three covid-19 symptoms: fever, a new and continuous cough, or a loss of taste or smell – which many experts considered too limited.
Now, as 4.9 million people were estimated to be infected in the UK in the week ending 26 March, the NHS has expanded its symptom list to include:
- Shortness of breath
- Fatigue or exhaustion
- Body aches
- A headache
- A sore throat
- A blocked or runny nose
- Loss of appetite
- Nausea or vomiting
This list more closely matches that of the US Centers for Disease Control and Prevention, which recognised many of these symptoms early in the pandemic.
The NHS’ list stops short of some of the World Health Organization’s (WHO) symptoms, however, which also considers skin rashes, red or irritated eyes, or discolouration of the fingers or toes to be less common signs of infection. Chest pain, confusion, or a loss of speech or mobility can occur in severe cases, according to WHO.
Writing on Twitter, Tim Spector, lead scientist of the Zoe covid-19 symptom tracker app, said: “NHS official Main symptoms of coronavirus (COVID-19) have finally changed after 2 years of lobbying and Zoe app user input – hurrah!”
Last month, Spector said the UK’s narrow symptom list was probably contributing to its infection surge.
“Many people are no longer isolating when they have symptoms, either because they feel they don’t have to anymore or because they or their employers still don’t recognise symptoms like runny nose or sore throat as covid,” he said.
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Covid-19 vaccines are being rolled out for 5- to 11-year-olds in England. In February, the UK’s Joint Committee on Vaccination and Immunisation said two low-dose vaccines, administered 12 weeks apart, would prevent “a very small number of children from serious illness and hospitalisation” in any future covid-19 wave. Vaccination programmes were already underway for this age group in the rest of the UK.
Shanghai’s recorded covid-19 cases are increasing. The locked-down city in China recently extended its restrictions, despite initial signs that infections may be declining. On April 3, Shanghai reported 8581 new asymptomatic covid-19 cases and 425 symptomatic cases, compared with 7788 new asymptomatic cases and 438 symptomatic cases the day before.
Bizarre lockdown dreams may have reflected our claustrophobia and sense of being out of control. University College London researchers analysed more than 850 dreams submitted online to the Lockdown Dreams project between March 2020 and March 2021. From 23 March to 15 June 2020, which corresponds with the UK’s first lockdown, just over seven in 10 (71 per cent) of the participants reported having more vivid dreams, compared with pre-pandemic. These included being locked indoors or unable to get to loved ones standing outside.
People living in the city’s eastern districts were due to come out of a five-day lockdown today
On 28 March, China’s largest city introduced a two-stage, 10-day lockdown in a bid to control its omicron outbreak. Initially, the lockdown was planned to affect eastern Shanghai for five days, followed by an additional five days of restrictions in the city’s western districts.
China’s health officials announced on 31 March they will instead lift restrictions on the east side in stages. With western Shanghai starting its five-day restrictions today, these extended measures plunge the city’s 26-million-strong population into lockdown.
People are instructed not to leave their homes, even to dispose of rubbish or walk their dogs, Reuters reported. Most of the city’s public transport has also been suspended and all non-essential businesses are closed.
Despite the lockdown extension, Shanghai’s reported case numbers are falling. On 31 March, the city reported 4144 new asymptomatic cases and 358 new symptomatic cases, compared with 5298 asymptomatic cases and 355 symptomatic cases the day before.
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Nearly all secondary school students in England have antibodies against the SARS-CoV-2 virus, according to the Office for National Statistics’ Covid-19 Schools Infection Survey. More than 7000 primary and secondary students from 150 schools were tested for antibodies in January and February. Extrapolating the results out across England, an estimated 96.6 per cent of secondary school students and 62.4 per cent of primary school pupils had SARS-Cov-2 antibodies at the beginning of the year. England is due to roll out a low-dose Pfizer/BioNTech vaccine for five- to 11-year-olds this month, which will include most primary pupils. The pre-existing antibodies among younger children therefore came about via a natural infection.
Pregnant people who are vaccinated against SARS-CoV-2 virus are almost twice as likely to get covid-19 compared with people who are vaccinated but not pregnant, according to an analysis of about 14 million hospital patients in the US. Pregnancy is the greatest risk factor for breakthrough covid-19 infections, above being an organ transplant recipient or having an immune system deficiency, the study found. This may be because certain aspects of the immune system are suppressed during pregnancy.
Covid-19 vaccines provide significantly more protection among people who have previously been infected with SARS-CoV-2 virus, according to two studies published in the journal Lancet Infectious Diseases. A Brazilian study linked the CoronaVac, Oxford/Astrazeneca, Janssen and Pfizer/BioNTech vaccines to increased protection against a moderate-to-severe reinfection, while a Swedish study found covid-19 vaccination provides at least nine months’ of additional protection for people who have had the virus before. The studies did not look at the level of protection among people who fought off covid-19 after catching it post-vaccination.
See previous updates from March 2022, February 2022, January 2022, November to December 2021, September to October 2021, July to September 2021, June to July 2021, May 2021, April-March 2021, February 2021, January 2021, November/December 2020, and March to November 2020.
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