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Everything we know about the EG.5 covid-19 variant and its symptoms

Chen Ly — Mon, 14 Aug 2023 16:41:13 +0000

A coronavirus test in Milford, Connecticut, in February 2022

U S Army/ZUMA Press Wire Service/Shutterstock

Recorded coronavirus cases are on the rise around the world, including in countries such as the UK, US and China. Last week, the World 91ɫ��Ƭ Organization (WHO) named an omicron subvariant called EG.5, or “Eris”, as a variant of interest, directing governments to keep a close eye on it. Here’s what we know so far.

What is EG.5?

EG.5 is a descendant of the SARS-CoV-2 omicron variant, which was first recorded in November 2021. It is closely related to XBB.1.9.2, another omicron subvariant, but has an extra spike protein mutation. by at the University of Guelph, Canada.

The subvariant also has an offshoot, dubbed EG.5.1, which contains an additional spike protein mutation.

EG.5 was first reported to the WHO on 17 February and was placed under monitoring on 19 July. On 9 August, after growing numbers of recorded EG.5 cases, the organisation designated it – along with EG.5.1 – as a “variant of interest”, advising health authorities to carefully monitor its transmission.

Where has EG.5 been identified? And how prevalent is it?

Globally, reports of EG.5 have been surging. In the week ending 23 July, 17.4 per cent of all sequenced SARS-CoV-2 cases were identified as EG.5, compared with just 7.6 per cent in the previous month.

As of 7 August, EG.5 cases had been reported to the Global Initiative on Sharing All Influenza Data by 51 countries, including China, the US, Australia and Japan.

“EG.5 is gradually taking over as the dominant variant in many countries,” says at the University of Glasgow, UK, replacing its closely related subvariant XBB.1.16.

In the US, the Centers for Disease Control and Prevention estimates that , making it the fastest growing and most common version of SARS-CoV-2 in the country.

Meanwhile, the UK 91ɫ��Ƭ Security Agency estimates that .

Does EG.5 cause more severe illness than previous variants?

The WHO has evaluated the health risk posed by EG.5 as being low and similar to that of other omicron subvariants.

“We don’t detect a change in severity compared to other omicron subvariants,” Maria Van Kerkhove at the WHO .

Is it more contagious? And does it evade vaccines?

EG.5’s extra spike protein mutation gives it a transmission advantage over previously dominant variants, says Willett. The same mutation also affects how antibodies neutralise the virus, which may enable it to evade immunity brought about by a prior SARS-CoV-2 infection or vaccination, he says.

What are EG.5’s symptoms? How long do they last?

As with other SARS-CoV-2 variants, EG.5 most commonly causes fever, a cough, fatigue and a loss of taste or smell. It can also cause a sore throat, headache, aches and pains, diarrhoea, rashes and eye irritation.

Read more

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EG.5’s symptoms last no longer than any other SARS-CoV-2 variant or subvariant, generally resolving within one to two weeks in mild cases.

How can we protect ourselves against EG.5?

For those who are particularly at risk of covid-19, such as older people and those with compromised immune systems, it is important to keep up with vaccine doses. In the UK, for example, the Joint Committee on Vaccination and Immunisation has recently announced that in the coming months.

“Levels of immunity are waning as it is now some time since most people were vaccinated or boosted,” says Willett. To avoid infection, the general advice of regular handwashing still applies, he says.

Covid-19 may have started in raccoon dogs, new DNA evidence shows

Clare Wilson — Fri, 17 Mar 2023 18:29:40 +0000

Raccoon dogs (Nyctereutes procyonoides) have previously been found to be susceptible to SARS-CoV-2 and to be capable of spreading it

Michael Breuer

The long-running debate over the origins of covid-19 took another turn this week, after a French scientist spotted that genetic sequences put on a database by Chinese researchers suggest that the coronavirus responsible might have come from animals such as raccoon dogs at the Huanan Seafood Market in Wuhan. Within a few days, the sequences were removed by the same researchers – although some other scientists managed to download them beforehand and are investigating further. “It is really critical that any and all data that relates to how this pandemic began be made available immediately,” at the World 91ɫ��Ƭ Organization (WHO) said at a press conference on 17 March. “There are several hypotheses that need to be examined, including how the virus entered the human population, either from a bat, through an intermediate host or through a breach in biosecurity from a lab. And we don’t have a definitive answer.” The Huanan market has long been seen as a probable origin for the SARS-CoV-2 coronavirus, as many of the first cases of covid-19, in December 2019, were in people with a connection to it and the stalls sold a range of live and dead animals, not just seafood. SARS-CoV-2’s original host is thought to be bats, as they carry many coronaviruses, although they haven’t yet been found with SARS-CoV-2. The ancestor of this virus may have jumped from bats to an intermediate host sold at the market, and then to people. An alternative explanation is that the virus escaped from the Wuhan Institute of Virology, where researchers were known to be studying bat coronaviruses, but not SARS-CoV-2. While this is a less-favoured idea among scientists, in February, the US Department of Energy said it was the , but didn’t release supporting evidence.

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Now, genetic sequences uploaded onto a global virology database called GISAID by the Chinese Center for Disease Control and Prevention may have shed more light on SARS-CoV-2’s origin. These sequences were derived from swabs taken from various surfaces at the market in early 2020 after it had been shut down. They were noticed by at the French National Centre for Scientific Research, who shared her findings with the WHO on 14 March. “I was focusing on market sequences when I logged in, but I was not expecting to find the data I found,” says Débarre. Débarre declined to say any more until her analysis is complete, but Van Kerkhove said at the press conference: “Amongst the samples that were positive for SARS-CoV-2, they saw evidence of DNA of animals. Some of these animals include raccoon dogs.” Raccoon dogs (Nyctereutes procyonoides) have previously been found to be susceptible to SARS-CoV-2 and to be capable of spreading it. “We know they are good at carrying it,” says at the University of Hong Kong. This doesn’t prove that raccoon dogs or any of the other animals at the market were infected with the virus in December 2019 and such evidence is now impossible to source, says Hughes. at the Francis Crick Institute in London says: “The data would appear to provide convincing evidence that raccoon dogs and other animals were present at the market at a critical time. This is another link in the chain that you would expect to see if the pandemic started that way.” Off the back of the information Débarre shared, Van Kerkhove said that the WHO has asked the Chinese Center for Disease Control and Prevention to rerelease the genetic data. “The big issue is that this data exists and that it is not readily available to the international community, not to mention that it should have been made available years earlier.”

Lion infected with covid-19 probably passed it on to two zoo workers

Soumya Sagar — Sat, 04 Mar 2023 12:00:35 +0000

A lion at Potawatomi Zoo in South Bend, Indiana, tested positive for the SARS-CoV-2 coronavirus after it started coughing and became breathless. Zoo workers who had cared for the lion later caught the infection

Covid-19 pandemic tied to antibiotic resistance in pneumonia bacterium

Carissa Wong — Thu, 16 Feb 2023 16:39:41 +0000

A modelling study suggests that the proportion of cases involving pneumonia-causing bacteria that are resistant to antibiotics has increased amid the covid-19 pandemic

Inhaled powder that coats airways can block coronavirus infection

Alice Klein — Thu, 09 Feb 2023 16:00:48 +0000

A gel that lines the respiratory tract prevented coronavirus infections in mice and monkeys, and may also work against any future new variants

AI detects if YouTubers are infected with omicron coronavirus variant

Soumya Sagar — Thu, 19 Jan 2023 12:30:45 +0000

An artificial intelligence picked up on audio samples where the speaker was probably infected with omicron with 80 per cent accuracy, potentially offering an inexpensive way of tracking cases

Why we probably won’t get new covid-19 vaccines in 2023

Michael Le Page — Wed, 28 Dec 2022 18:00:00 +0000

Any new covid-19 vaccine must be better than the ones we already have, setting a high bar for approval that is not expected to be met in 2023

The covid-19 pandemic’s third year saw countries adopt new approaches

New Scientist staff — Wed, 14 Dec 2022 18:00:00 +0000

As the world faced the third year of the coronavirus pandemic, Iceland began 2022 by shifting towards "herd immunity" while China ended the year easing its zero covid approach

Nearly 15 million excess deaths occurred globally in 2020 and 2021

Carissa Wong — Wed, 14 Dec 2022 16:02:43 +0000

A person has their temperature checked before entering a market in the Coata district of Peru in July 2020

CARLOS MAMANI/AFP/Getty Images

Nearly 15 million excess deaths from any cause may have occurred during 2020 and 2021, nearly three times the 5.42 million covid-19 fatalities that were reported over the same two-year period.

at the World 91ɫ��Ƭ Organization in Geneva, Switzerland, and his colleagues estimated the number of deaths that would have occurred globally from January 2020 to December 2021 if the pandemic hadn’t taken place.

For some countries, the team used mortality data from 2015 to 2019 to calculate the number of expected deaths per year, which they compared with the number of reported deaths from any cause over two years of the pandemic.

In the countries that lacked the necessary mortality data, such as some in Africa and the Middle East, the researchers used a statistical model to predict their excess deaths. Based on countries where mortality statistics are available, the model linked excess fatalities with factors that can influence death rates, such as covid-19 restrictions and the prevalence of other conditions, such as diabetes.

Results suggest 14.83 million excess deaths occurred worldwide from the start of 2020 to the end of 2021, of which just under 5 million were in 2020 and more than 10 million were in 2021.

“We think the doubling in mortality in 2021 compared to 2020 is not only due to more infectious [covid-19] variants, but also because covid-19 was spreading into populations that had less access to vaccination,” says Msemburi.

Excess deaths may also include people who died from non-covid causes following delayed health screenings or because of a reluctance to seek medical attention amid the height of the pandemic.

The country with the most excess deaths relative to its expected number of fatalities was Peru, which saw twice as many deaths from 2020 to 2021 compared with what would have been expected if the pandemic had not occurred. This was followed by Ecuador and Bolivia, which each had 1.5 times more deaths.

“This does not mean these countries responded worse to the pandemic, there are many factors that could be at play, including the timing of outbreaks in different countries, which covid-19 variants were dominant, as well as vaccination rates,” says Msemburi. Peru, for example, may have also improved its reporting of deaths amid the pandemic, creating the illusion of an increase in excess fatalities, he says.

“Comparing excess mortality in different countries can be of aid in evaluating the impact of different measures taken by governments around the world, which may in turn aid in fighting future pandemics,” says at the Ludwig Maximilian University of Munich, Germany.

Nevertheless, for many countries in the study, the expected deaths from 2020 to 2021 were predicted using a model that doesn’t account for the fact that populations may be ageing or becoming younger, says De Nicola. An ageing population would increase the expected mortality and reduce the estimated excess mortality, he says.

“We are making further improvements to the model that will improve the estimates,” says Msemburi. In addition, reported covid-19 cases and deaths are always below their true numbers, he says.

Nature

Drug that targets ACE2 receptors may work against new covid variants

Carissa Wong — Mon, 05 Dec 2022 16:02:15 +0000

The omicron coronavirus variant binding to a cell’s ACE2 receptor

DESIGN CELLS/SCIENCE PHOTO LIBRARY/Alamy

A drug that targets the ��ǰ��ǲԲ��ܲ�’ entry point into cells could protect against the infection as new variants emerge. Existing treatments and vaccines work against SARS-CoV-2 itself, raising the risk that these will become less effective as the virus mutates and evolves to evade immunity. at the University of Cambridge and his colleagues were studying conditions that affect bile ducts when they found that a molecule called FXR regulates the activity of the ACE2 receptor. Present on the surfaces of many cells, SARS-CoV-2’s spike protein binds to this receptor to gain entry into cells. In turn, the researchers confirmed previous findings that the drug ursodeoxycholic acid (UDCA), which is approved to treat gallstones and liver conditions in the UK and the US, regulates FXR. To test UDCA’s potential regarding covid-19, the researchers gave nine hamsters the drug at a similar dose to that given to humans. Six other hamsters were given a saline solution. One week later, the animals were put into a cage with hamsters that were infected with the delta coronavirus variant. Four days later, the hamsters were euthanised and the team analysed their lung samples for SARS-CoV-2’s genetic material. One-third of the hamsters treated with UDCA caught the virus, compared with all the animals given the saline solution. The hamsters had free access to food during the experiment. Nevertheless, those given the saline solution had lost about 9 per cent of their body weight four days after catching SARS-CoV-2. In contrast, the animals treated with UDCA gained some weight by the end of the study. This suggests that, even among the UDCA-treated hamsters that caught covid-19, the drug reduced its severity. “The drug will not fully prevent any virus entering cells, but it prevents how much virus enters cells and how much it replicates,” says Sampaziotis. Next, the team tested UDCA on a set of human lungs in a laboratory. The lungs, which were functioning via a ventilator, came from an organ donor but weren’t suitable for transplantation. UDCA was injected into one lung and a saline solution was injected into the other. Six hours later, levels of ACE2 in the UDCA-treated lung had roughly halved, on average, while little change occurred in the control lung. Neither the mice nor the lungs’ organ donor were immunocompromised, but a drug like UDCA could particularly benefit people with suppressed immune systems, who may launch less of an immune response after being vaccinated against covid-19. Some people with suppressed immune systems are offered the treatment to prevent covid-19. This contains antibodies that bind to ACE2, preventing SARS-CoV-2’s spike protein from attaching to the receptor. SARS-CoV-2 rapidly mutates into new variants with an altered spike protein, making antibody treatments less effective. “ACE2 is like a doorway, which lets the virus go in the cell,” says Sampaziotis. “If you manage to close the door, this means the virus can’t replicate itself and we could prevent the infection in a way that doesn’t rely on the immune system.” UDCA can’t replace vaccination, which is the best method we have for preventing covid-19, but the treatments could work together to reduce an individual’s risk, says Sampaziotis. The researchers are working to set up clinical trials to determine if UDCA’s effects in animals and human organs translate to people.