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Some people are naturally resistant to covid-19 and the discovery could lead to a universal vaccine against multiple coronaviruses

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Illustration of a T cell targeting SARS-CoV-2 particles

JUAN GAERTNER/SCIENCE PHOTO LIBRARY

Many groups worldwide are trying to develop vaccines that protect against a wide range of coronaviruses and prevent another pandemic. These efforts have now been boosted by the discovery that some healthcare workers had pre-existing immunity to the SARS-CoV-2 virus during the first wave of the pandemic.

During the first half of 2020, around 700 healthcare workers in the UK were tested weekly as part of a crowdfunded study called COVIDsortium. Most of these people, who wore protective equipment, never tested positive for covid-19 in PCR tests or developed covid-19 antibodies – proteins that bind to the outside of viruses, preventing cells from being infected.

However, when Leo Swadling and Mala Maini at University College London and their colleagues looked more closely, they found some of those who tested negative had a protein in their blood that is linked to covid-19 infection, as well as T cell responses to the SARS-CoV-2 virus. T cells are part of the immune system. It appears these people had what Swadling calls an “abortive infection”, where a strong, early T cell response enabled them to get rid of the virus very quickly.

Cells infected by viruses sound the alarm by displaying viral proteins on their surface, and T cells are the immune cells that learn to recognise these proteins and destroy infected cells. Crucially, while antibodies can only target proteins on the outside of a virus, T cells can learn to recognise any viral proteins.

When the team looked at early blood samples from the people who had an abortive infection, they found that even before being exposed to SARS-CoV-2, they had some T cells that could recognise the proteins that this virus uses to replicate itself inside infected cells.

The most likely explanation is that these people were often exposed to the existing human coronaviruses that cause around 10 per cent of colds, says Maini. “We don’t know the historic infections of these individuals, so we don’t know for sure where the T cells are coming from,” she says.

Preventing another pandemic

The proteins involved in viral replication are very similar in SARS-CoV-2 and other human and animal coronaviruses, meaning that if vaccines can be developed that elicit a strong T cell response against these proteins, they should protect against a very broad range of coronaviruses – a so-called universal or pan-coronavirus vaccine. One way to do this would be to add mRNAs coding for these proteins to mRNA vaccines that target the virus’s external spike protein.

Adding extra components to the next generation of coronavirus vaccines might protect both against any new variants that might evolve and against animal coronaviruses that could jump into people and spark a new pandemic, says Swadling. “There is a strong rationale for adding these proteins alongside the spike protein,” he says.

Many groups are already trying to develop coronavirus vaccines that provide broader protection, says Olga Pleguezuelos at UK-based company SEEK. Her team has already created such a vaccine based on the most conserved parts of coronavirus proteins. “It’s a matter of time before another of these members [of the coronavirus family] creates an epidemic or pandemic,” she says. “If we end up with something that is as infectious as covid and as lethal as MERS, then we are in serious trouble.”

However, it isn’t clear how effective a vaccine that only produces a T cell response would be, Maini says. Most vaccines work by stimulating an antibody response, though many do also produce a T cell response.

Many groups are developing universal flu vaccines based on eliciting a T cell response, but so far these haven’t proved highly effective. Other teams are instead focusing on getting antibodies to target parts of the outer viral proteins of the flu virus that don’t mutate. However, this won’t work with coronaviruses, says Peter Palese at the Icahn School of Medicine at Mount Sinai in New York. “They just don’t have a conserved region.”

Journal reference: Nature, DOI: 10.1038/s41586-021-04186-8

 

 

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Solar storms may cause up to 5500 heart-related deaths in a given year

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In an approximate 11-year cycle, the sun blasts out charged particles and magnetised plasma that can distort Earth’s magnetic field, which may disrupt our body clock and ultimately affect our heart



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17 June 2022

A solar storm

Jurik Peter/Shutterstock

Solar storms that disrupt Earth’s magnetic field may cause up to 5500 heart-related deaths in the US in a given year.

The sun goes through cycles of high and low activity that repeat approximately every 11 years. During periods of high activity, it blasts out charged particles and magnetised plasma that can distort Earth’s magnetic field.

These so-called solar storms can cause glitches in our power grids and bring down Earth-orbiting satellites. A handful of studies have also hinted that they increase the risk of …

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UK Covid infection rate rising, with more than a million cases in England | Coronavirus

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Coronavirus infections are rising in the UK, figures have revealed, with experts noting the increase is probably down to the more transmissible BA.4 and BA.5 Omicron variants.

The figures from the Office for National Statistics (ONS), based on swabs collected from randomly selected households, reveal that in the week ending 11 June an estimated one in 50 people in the community in England are thought to have had Covid – around 1.13 million people.

The figure is even higher, at one in 45, in both Wales and Northern Ireland, while it was highest in Scotland where, in the week ending 10 June, one in 30 people are thought to have been infected.

While the figures remain below the peak levels of infection seen earlier this year, when around one in 13 people in England had Covid, the findings are a rise on the previous week where one in 70 people in England were thought to be infected. Furthermore, the data reveals increases in all regions of England, except the north-east, and across all age groups.

Experts say that a key factor in the increase is probably the rise of the Covid variants of concern BA.4 and BA.5.

“Infections have increased across all four UK nations, driven by rising numbers of people infected with the BA.4 and BA.5 Omicron variants,” said Kara Steel, senior statistician for the Covid-19 Infection Survey.

While Steel said it remained too early to say if this was the start of another wave, others have warned it may already have begun, with increased mixing and travelling among other factors fuelling a rise in cases.

Among concerns scientists have raised are that BA.4, BA.5 and another variant on the rise, BA.2.12.1, replicate more efficiently in human lung cells than BA.2.

Prof Azra Ghani, an epidemiologist at Imperial College London, said the latest figures were not surprising, and might rise further.

“This increase in infection prevalence is likely due to the growth of the BA.4 and BA.5 Omicron subvariants, which as we have seen elsewhere in Europe, appear to be able to escape immunity generated from previous Omicron subvariants,” she said.

“It is therefore possible that we will continue to see some growth in infection prevalence in the coming weeks and consequently an increase in hospitalisations, although these subvariants do not currently appear to result in any significantly changed severity profile. This does however serve as a reminder that the Covid-19 pandemic is not over.”

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NHS to offer women in England drug that cuts recurrence of breast cancer | Breast cancer

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Thousands of women in England with breast cancer are to benefit from a new pill on the NHS which reduces the risk of the disease coming back.

The National Institute for Health and Care Excellence (Nice) has given the green light to abemaciclib, which cuts the chance of breast cancer returning after a patient has had surgery to remove a tumour.

Trials showed that patients who had the drug with hormone therapy had a more than 30% improved chance of their cancer not coming back after surgery, compared with hormone therapy alone.

“It’s fantastic thousands of women with this type of primary breast cancer will now have an additional treatment option available on the NHS to help further reduce the risk of the disease coming back,” said Delyth Morgan, the chief executive of charity Breast Cancer Now.

“The fear of breast cancer returning or spreading to other parts of their body and becoming incurable can cause considerable anxiety for so many women and their loved ones.

“New effective treatments such as abemaciclib, which can offer more women the chance to further reduce the risk of the disease recurring, are therefore extremely welcome and this is an important step change in the drug options available for this group of patients.”

The twice-a-day pill is suitable for women with hormone receptor-positive, HER2-negative, node-positive early breast cancer at high risk of recurrence who have had surgery. About 4,000 women will benefit initially, Nice said.

Helen Knight, the interim director of medicines evaluation at Nice, said the draft recommendation came less than a month after abemaciclib received its licence.

“The fact that we have been able to produce draft recommendations so quickly is testament to the success of our ambition to support patient access to clinically and cost effective treatments as early as possible,” said Knight. “Until now there have been no targeted treatments for people with this type of breast cancer.

“Abemaciclib with hormone therapy represents a significant improvement in how it is treated because being able to have a targeted treatment earlier after surgery will increase the chance of curing the disease and reduce the likelihood of developing incurable advanced disease.”

Abemaciclib works by targeting and inhibiting proteins in cancer cells which allow the cancer to divide and grow. It normally costs £2,950 for a packet of 56 150mg-tablets, but the manufacturer, Eli Lilly, has agreed an undisclosed discounted price for NHS England.

“Thanks in part to this latest deal struck by NHS England, NHS patients will be able to access another new targeted drug for a common and aggressive form of breast cancer,” said Prof Peter Johnson, the cancer director of NHS England.

“Abemaciclib, when used alongside a hormone therapy, offers a new, doubly targeted, treatment option, helping to increase the chances of beating the cancer for good, as well as meeting the NHS’s commitment to delivering improved cancer care under our long-term plan.”

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