Cheap covid-19 antibody test shows if you have immunity in 5 minutes


A cheap 5-minute test can accurately determine whether you have had covid-19 in the past or determine whether you have protection from a vaccine by detecting antibodies in blood or saliva.

When a person is infected with the coronavirus or is vaccinated against it, their immune system produces antibodies to fight the virus. These antibodies continue to be produced for at least six months, so they can be used to detect a past infection or vaccine response. Tests for coronavirus antibodies already exist, but they tend to be expensive, complicated or not very accurate.

Feng Yan at the Hong Kong Polytechnic University and his colleagues made a cheaper, more convenient covid-19 antibody test using organic electrochemical transistors. These convert biological signals to electrical signals, and are becoming popular for detecting biological molecules like proteins and glucose.

A drop of blood or saliva is placed on one of these transistors, which is made of gold and embedded in a small plastic strip. As coronavirus antibodies bind to it, the transistor produces electrical signals that are read by a lightweight portable meter connected via Bluetooth to a mobile phone. The whole process takes less than 5 minutes.

The test proved to be highly accurate at measuring coronavirus antibodies when it was tried on samples of blood and saliva that had been spiked with different antibody levels in the lab, including very low levels.

Yan and his colleagues are now planning a clinical trial to confirm the test also works in real-world settings. If the trial is successful, the team will apply for approval to sell the test, which should cost less than $1 per test strip, says Yan.

Ireland – Coronavirus testing regime may be scaled back significantly


Testing for Covid-19 would be radically scaled back under plans being considered by the National Public Health Emergency Team (Nphet), as harm associated with the virus is reduced.

A paper on transitioning away from the “unprecedented” mass testing regime that has been put in place details a “stepwise” approach away from the current system.

Among the first steps would be advising against testing vaccinated people with mild respiratory symptoms, and testing of children under 13 with mild symptoms to be discouraged if they do not deteriorate over 48 hours.

“The success of the vaccination programme requires a fundamental revaluation of the approach to testing for Sars-CoV-2 and how it links to the evolving public health response,” according the discussion paper, which was submitted to Nphet in late July and released under the Freedom of Information Act.

With Covid likely to become endemic in the global population, alongside reduced harm due to vaccines, “we need to begin to consider how we plan to transition towards placing testing … back in the framework within which we test for other infections,” the paper’s author, Prof Martin Cormican, argues.

Prof Cormican, who is the HSE’s leading expert on infection control, says this will mean testing for coronavirus “much more selectively”. This would mean usually testing only when requested by a healthcare professional, as part of managing an outbreak, or surveillance testing for the disease more in line with how the prevalence of other respiratory viruses is monitored.

“Planning for a transition from open access or mass scale… testing is important because as [harm] declines, the negative impacts of testing on the current scale are likely to become disproportionate to the benefits to human health.”

Blood test could reveal who is most likely to get severe covid-19


A simple blood test could help predict which people with covid-19 are likely to get severely ill and need to go on a ventilator. The test measures levels of antibodies in the blood that are directed against molecules released by dead blood cells, including their own DNA.

The test may also prove helpful in infected people before they reach the stage of needing hospital treatment, says Ana Rodriguez at NYU Langone in New York. It is likely to be less accurate in that group, but it could indicate who needs closer monitoring, she says.

People who get severely ill from covid-19 tend to deteriorate at least a week or more after symptoms begin, when virus levels are falling, suggesting it is something about the person’s reaction to the infection that causes their problems, rather than the virus itself.

Rodriguez’s team looked at blood tests done on 115 people admitted to hospital with covid-19 in 2020. About half of these people became severely ill and needed oxygen support, while the rest recovered quickly.

Those with high levels of antibodies directed against DNA or a fatty molecule from cell membranes called phosphatidylserine had about a 90 per cent chance of deteriorating. But the test only identified about a quarter of people who got worse. “It won’t mean we catch everybody but if you have this, it looks very bad,” says Rodriguez.

It is unclear if the antibodies detected by the test are involved in the person’s deterioration, or if they are innocent bystanders.

Rapid lateral flow tests 95% effective at detecting COVID if used when symptoms start, study shows


Rapid lateral flow tests are 95% effective at detecting coronavirus if they are used at the onset of infection or as soon as symptoms start, a new study suggests.

Scientists have previously said that lateral flow tests (LFTs) are less sensitive at picking up COVID-19 cases than laboratory tested PCR swabs.

But a study of more than 2,500 people with flu-like symptoms has shown that LFTs picked up 95% of the coronavirus cases that the PCR tests did.

It also correctly identified 89% of COVID cases as negative.

LFTs function like pregnancy tests and look for coronavirus proteins to detect cases and take just 30 minutes.

PCR (Polymerase Chain Reaction) tests are laboratory tested and can take up to three days to process.

The research, carried out by experts at Queen Mary University of London, Oxford University, the Institute for Advanced Studies in Vienna and the Medical University of Graz, is the first to compare the two forms of testing on a group of this scale.

Study of Pfizer in Israel shows 72% effective at preventing death after 1st dose


A real-world test of Pfizer’s COVID-19 vaccine in more than half a million people confirms that it’s very effective at preventing serious illness or death, even after one dose.

Wednesday’s published results, from a mass vaccination campaign in Israel, give strong reassurance that the benefits seen in smaller, limited testing persisted when the vaccine was used much more widely in a general population with various ages and health conditions.

The vaccine was 92% effective at preventing severe disease after two shots and 62% after one. Its estimated effectiveness for preventing death was 72% two to three weeks after the first shot, a rate that may improve as immunity builds over time.

It seemed as effective in folks over 70 as in younger people.

“This is immensely reassuring … better than I would have guessed,” said the Mayo Clinic’s Dr. Gregory Poland.

Strong decline in coronavirus across England since January, React study shows


There has been a “strong decline” in levels of coronavirus infections in England since January, say scientists tracking the epidemic.

Imperial College London’s React study found infections have dropped by two-thirds across England since lockdown began, with an 80% fall in London.

But virus levels are still high, with one in 200 testing positive between 4 and 13 February.

This is similar to levels seen in late September 2020.

Although these are interim findings, based on more than 85,000 swab tests from randomly selected people, they suggest social distancing and restrictions are having an impact.

Prof Paul Elliott, director of the programme at Imperial, said the drop in infection rates was “really encouraging”.

It comes as Prime Minister Boris Johnson prepares to receive new data on the effect of vaccines on the spread of coronavirus, ahead of Monday’s publication of a roadmap for easing the lockdown in England.

Covid vaccine impact revealed in over-80s blood tests


England’s vaccination programme is starting to pay off, with the over-80s age group now the most likely to test positive for coronavirus antibodies, Office for National Statistics testing suggests.

Blood tests reveal more over-80s than any other age group in England are showing signs of some immunity against Covid infection.

People have antibodies to Covid if they’ve had an infection in the last few months or if they have been vaccinated.

Previously, younger age groups who were more likely to be exposed to the virus were the most likely to test positive for antibodies.

In England, 41% of over-80s tested positive for antibodies, which the ONS said was “most likely due to the high vaccination rate in this group”.

Two weeks ago that figure was 26%.

It takes two to three weeks for immunity to build after vaccination.

Oxford vaccine could substantially cut spread


The Oxford-AstraZeneca vaccine could lead to a “substantial” fall in the spread of the virus, say scientists.

The impact of Covid vaccines on transmission has been a crucial unknown that will dramatically shape the future of the pandemic.

The study, which has not been formally published, also showed the vaccine remained effective while people waited for a second dose.

It was 76% effective during the three months after the first shot.

The impact on transmission is critical.

If a vaccine only stops you getting severely ill, but you can still catch and pass on the virus, then everyone will need to be immunised to be protected.

But if it also stops you spreading the virus then it would have a far greater impact on the pandemic as each person who is vaccinated indirectly protects other people too.

The study by the University of Oxford swabbed participants every week to test them for the presence of the virus.

If there is no virus then they cannot spread it. In the study, the numbers testing positive halved in people once they had been given two doses of the vaccine.

“The data indicate that [the vaccine] may have a substantial impact on transmission by reducing the number of infected individuals in the population,” the report said.

Oxford scientists preparing vaccine versions to combat emerging virus variants


Oxford scientists are preparing to rapidly produce new versions of their vaccine to combat emerging more contagious COVID-19 variants discovered in the UK, South Africa and Brazil, The Telegraph reported on Wednesday.

The team behind the vaccine from Oxford and AstraZeneca Plc is undertaking feasibility studies to reconfigure the technology, the newspaper said, citing a confirmation from Oxford University.

The scientists were working on estimating how quickly they could reconfigure their ChAdOx vaccine platform, the report said.

Recent laboratory tests have indicated that the COVID-19 vaccine developed by Pfizer Inc and partner BioNTech SE is likely to work against the UK variant spreading around the world.

BioNTech has said it plans to publish a more detailed analysis of the likely effect of its vaccine on the South African variant within a few days.

AstraZeneca Plc, Moderna Inc and CureVac NV are also testing whether their respective shots will protect against the fast-spreading variants.

Australia on track to record zero COVID-19 cases for second straight day


Australia is on course to record its second straight day of zero local COVID-19 cases, helped by tougher restrictions on public movement and internal borders, but authorities continued to urge more people to get tested to track undetected cases.

Australia has been seeking to contain fresh virus outbreaks since last month with impacted regions placed under lockdown and masks made mandatory indoors but infection rates seem to have stabilised after low cases in recent days.

New South Wales (NSW), the country’s most populous state, flagged it could ease restrictions soon if testing numbers rise as more tests could help trace all unknown infections.