UK – ONS data shows infections in the over 70s have halved in the last three weeks. why? boosters


AstraZeneca’s antibody cocktail helps prevent COVID-19 for at least 6 months


AstraZeneca on Thursday cemented its lead in bringing a preventative COVID-19 shot to market, saying its antibody cocktail offered 83% protection over six months, providing another possible weapon in the fight against the pandemic.

The therapy, called AZD7442 or Evusheld, had previously been shown to confer 77% protection against symptomatic illness after three months, in an earlier readout of the late-stage PROVENT trial in August. read more

The data give hope of additional protection for people who do not respond well to vaccines, such as cancer patients.

The Anglo-Swedish company also said a separate study in patients with mild-to-moderate COVID-19 showed a higher dose of AZD7442 cut the risk of symptoms worsening by 88% when given within three days of the first symptoms.

Air filter significantly reduces presence of airborne SARS-CoV-2 in COVID-19 wards


When a team of doctors, scientists and engineers at Addenbrooke’s Hospital and the University of Cambridge placed an air filtration machine in COVID-19 wards, they found that it removed almost all traces of airborne SARS-CoV-2.

While the discovery could have implications for improving the safety of repurposed ‘surge wards’, the researchers say it also opens up the possibility of being able to set standards for cleaner air to reduce the risk of airborne transmission of infections.

Over the duration of the pandemic there has been a steady rise in the evidence that the SARS-CoV-2 virus can be transmitted through the air in small droplets (aerosols). But as hospitals have seen their capacity overwhelmed, they have been forced to manage many of their COVID-19 patients in repurposed ‘surge’ wards, which often lack the ability to change the air with a high frequency. While the use of appropriate personal protective equipment (PPE) protects staff and patients significantly reduces the risk of transmission, there are still reports of patient-to-healthcare worker transmission of the virus, potentially through the inhalation of viral particles.

A team at the University of Cambridge and Cambridge University Hospitals (CUH) NHS Foundation Trust investigated whether portable air filtration/UV sterilisation devices could reduce airborne SARS- CoV-2 in general wards that had been repurposed as a COVID ward and a COVID Intensive Care Unit (ICU). The results are published in Clinical Infectious Diseases.

Dr Vilas Navapurkar, a Consultant in Intensive Care Medicine at CUH, who led the study, said: “Reducing airborne transmission of the coronavirus is extremely important for the safety of both patients and staff. Effective PPE has made a huge difference, but anything we can do to reduce the risk further is important.”

“Because of the numbers of patients being admitted with COVID-19, hospitals have had to use wards not designed for managing respiratory infections. During an intensely busy time, we were able to pull together a team from across the hospital and University to test whether portable air filtration devices, which are relatively inexpensive, might remove airborne SARS-CoV-2 and make these wards safer.”

The team performed their study in two repurposed COVID-19 units in Addenbrooke’s Hospital. One area was a surge ward managing patients who required simple oxygen treatment or no respiratory support; the second was a surge ICU managing patients who required ventilation either through non-invasive mask ventilation or invasive respiratory support, such as involving the use of an invasive tube and tracheostomy.

UK – Covid booster doses will be offered to over-40s


All over-40s in the UK will be offered a third dose of a Covid vaccine, after advice from the government scientists.

The move would top up protection and help limit the spread of the virus over winter.

Three doses cuts the risk of infection by more than 93%, according to new data from the UK Health Security Agency.

The Joint Committee on Vaccination and Immunisation also said 16- and 17-year-olds, initially offered only a single dose, should now receive a second.

So far, 12.6 million people have had a booster dose.

They have been given to the over-50s, front-line medical staff and people with health conditions that put them at greater risk.

Prime Minister Boris Johnson said it would be an “utter tragedy” if double vaccinated people became seriously ill or died “because they allowed their immunity to wane”.

He said there was “nothing in the data” to suggest a lockdown or Plan B was needed at the moment; despite “storm clouds” gathering in Europe, where cases are climbing.

Boosters not only replenish immunity against transmission but lift it too, new data shows


When people talk about the effectiveness or otherwise of vaccines they often mean one of two things. There is the extent to which a vaccine can protect you against infection: Will it stop you catching COVID? And there’s the protection a vaccine gives you against serious harm: If I catch COVID will it prevent me going to hospital or dying?

These two types of protection – against transmission and against severe disease – are both very important, but they are also quite different. Just because a particular vaccine is good at one thing doesn’t necessarily mean it’s equally good at the other thing. Just because a particular vaccine’s effectiveness at preventing transmission is waning doesn’t necessarily mean its effectiveness at preventing serious disease is diminishing at the same rate.

I say all of this not just because the two types of protection are often conflated (though they are) but because keeping this distinction under your hat is quite important when navigating all the data around COVID and vaccines.

And to be absolutely clear, the majority of what’s below is about that first type of protection: Protection against transmission.

As you’ll probably be aware, the big picture here is that immunity against transmission has been waning recently. Here’s one way of looking at it. If you got the Pfizer vaccine, its “vaccine effectiveness” (an epidemiological term meaning the extent of protection it grants you vs someone who’s unvaccinated) was 92% straight after your second dose. But over the following weeks that immunity wanes, down to 69.7% by week 20.

The protection granted by AstraZeneca was lower to start with at 63% straight after dose two, falling to 47.3% by week 20. Now, these numbers are specifically about the Delta variant. From what we know, these vaccines were a touch better (a lot better in AstraZeneca’s case) at protecting against, for instance, the Alpha/Kent variant. Even so, it’s clear both that they are not as high as everyone would like and they are heading downwards.

Which brings us to the new data published today by the UK Health and Security Agency (better known as the agency formerly known as Public Health England) on the early evidence from the UK’s booster programme. The news here is very promising. It suggests that two weeks after a booster dose of Pfizer, those who originally had two doses of AstraZeneca are up to 93.1% protection and those who originally had two Pfizer jabs are up to 94% protection.

In other words, it’s not just that the booster jabs replenish that immunity, they lift it up beyond where it was at two doses – a little bit higher for team Pfizer and a lot higher for team AstraZeneca.

Millions to be offered Covid booster jabs earlier to protect NHS over winter


The government is to allow people to have their Covid booster jab after five months, a month sooner than the current policy, in an effort to help stop the NHS becoming overwhelmed this winter.

This major change to the vaccination programme could see ministers flouting the advice of the Joint Committee on Vaccination and Immunisation, which recommends that people should wait until six months after their second dose before having their top-up in order to maximise protection.

It means that millions of Britons will be able to have their booster sooner than expected to reduce the risk of hospitals failing to cope with large numbers of people becoming seriously ill with Covid during the winter months, when they always come under intense pressure.

UK researchers identify T-cell targets for future COVID vaccines


British researchers said on Wednesday they had identified proteins in the coronavirus that are recognised by T-cells of people who are exposed to the virus but resist infection, possibly providing a new target for vaccine developers.

Immunity against COVID-19 is a complex picture, and while there is evidence of waning antibody levels six months after vaccination, T-cells are also believed to play a vital role in providing protection.

The University College London (UCL) researchers examined 731 health workers in two London hospitals during the first wave of the COVID-19 pandemic, and found that many had not tested positive despite likely exposure to the original coronavirus.

“What is really informative is that the T-cells detected in these individuals, where the virus failed to establish a successful infection, preferentially target different regions of the virus to those seen after infection.”

Current vaccines, which provide high protection against severe disease but do not fully stop transmission or re-infection, target the spike protein of the coronavirus.

In contrast, the T-cell responses that led to abortive infections in the UCL study recognised and targeted instead “replication proteins”.

They added that the replication proteins are among the least changed by mutations to coronaviruses, and exposure to other coronaviruses may be one reason why some of the health workers were able to mount such quick T cell responses.

It also means that a vaccine which targeted these proteins in addition to the spike protein should work against a broad range of coronaviruses including the currently dominant Delta variant, the researchers said.

“This is a strong rationale for including these proteins to supplement spike in next-generation vaccines,” Swadling told reporters.