Germany recommends mixing Covid vaccines, saying it gives 'significantly superior' immune response

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Germany has recommended mixing Covid-19 vaccine types, saying it gives a ‘significantly superior’ immune response than two AstraZeneca shots.

For those that got the Oxford University-developed jab as their first dose, the country is recommending they switch to a different shot for their second.  

The aim is to increase the speed and effectiveness of vaccinations as the more contagious delta variant spreads through Europe, causing Covid cases to rise. 

Like many countries in the EU, Germany’s vaccination started slow, and while it has picked up pace, it is still far behind the likes of the UK and the US.

This in part is due to a supply row earlier this year between the EU and the Anglo-Swedish pharmaceutical firm AstraZeneca, and countries – including Germany and France – questioning the safety of the vaccine earlier in their jab programmes. 

Pictured: Vials of Pfizer-BioNTech, AstraZeneca, and Moderna coronavirus disease (COVID-19) vaccine (file photo). Germany has recommended mixing Covid-19 vaccine doses, saying it gives a 'significantly superior' immune response than two AstraZeneca shots

Pictured: Vials of Pfizer-BioNTech, AstraZeneca, and Moderna coronavirus disease (COVID-19) vaccine (file photo). Germany has recommended mixing Covid-19 vaccine doses, saying it gives a ‘significantly superior’ immune response than two AstraZeneca shots

Health Minister Jens Spahn conferred with his colleagues from Germany’s 16 states on Friday, the day after the country’s standing committee on vaccination issued a draft recommendation. 

In a statement, the committee said that ‘according to current study results,’ the immune response from a mixture of AstraZeneca with an mRNA vaccine was ‘significantly superior’ to that from two doses of AstraZeneca.

It recommended that the second dose with an mRNA vaccine – Germany uses those made by BioNTech-Pfizer and Moderna – be administered four weeks or more after the first AstraZeneca shot. 

That is much shorter than the nine to 12 weeks the committee recommends between two doses of AstraZeneca, which is a viral vector-based vaccine.

Pictured: Germany's Health Minister Jens Spahn. He conferred with his colleagues from Germany's 16 states on Friday, the day after the country's standing committee on vaccination issued a draft recommendation about using difference

Pictured: Germany’s Health Minister Jens Spahn. He conferred with his colleagues from Germany’s 16 states on Friday, the day after the country’s standing committee on vaccination issued a draft recommendation about using difference 

Mixing AstraZeneca and Pfizer Covid vaccines  generates ‘robust’ immune response, study finds

By Mary Kekatos, Acting U.S. Health Editor for DailyMail.com and PA Media 

Mixing doses of the AstraZeneca-Oxford and Pfizer-BioNTech vaccines generates a robust immune response against COVID-19, research suggests.

The study found that using Pfizer followed by AstraZeneca or vice versa induced high concentrations of antibodies against the spike protein of the virus when doses were given four weeks apart.  

However, the Com-COV study, run by the University of Oxford, found that the order of vaccines made a difference.

AstraZeneca followed by Pfizer induced higher antibodies and T cell responses than Pfizer followed by AstraZeneca.

But both schedules induced higher antibodies than the licensed, and highly effective, standard two-dose AstraZeneca schedule.  

The findings could allow flexibility in the UK and global vaccine rollouts, allowing people to receive whatever jab is available, rather than waiting for a matching one.  

‘The Com-COV study has evaluated “mix and match” combinations of the Oxford and Pfizer vaccines to see to what extent these vaccines can be used interchangeably, potentially allowing flexibility in the UK and global vaccine rollout,’ said chief investigator Dr Matthew Snape, associate professor in pediatrics and vaccinology at the University of Oxford

‘The results show that when given at a four-week interval both mixed schedules induce an immune response that is above the threshold set by the standard schedule of the Oxford/AstraZeneca vaccine.’

The committee, known by its German acronym STIKO, didn’t detail what studies its conclusion was based on. 

Germany’s disease control centre noted that it was a draft, and that a final recommendation with more detail and sourcing will follow. 

Researchers have said that mixing vaccines is likely safe and effective, but are still gathering data to be sure.

German authorities already decided in April that under-60s who had received a first AstraZeneca shot should as a rule get a second shot of an mRNA vaccine. 

The decision came after the AstraZeneca vaccine was linked to extremely rare blood clots in younger people. Germany recommends that under-60s consult with a doctor before taking it.

Spahn said Friday that enough mRNA vaccine is available to implement the new recommendation quickly and that it ‘makes the AstraZeneca vaccine more attractive,’ with large quantities now arriving and the prospect of a much shorter wait for the second shot.

He said the head of STIKO told ministers that the combination of AstraZeneca and BioNTech ‘protects as least as well as BioNTech-BioNTech as a combination, in some cases even better.’ 

But he also stressed that two doses of AstraZeneca give good protection. BioNTech-Pfizer has been the mainstay of Germany’s campaign, with AstraZeneca a distant second in terms of doses administered.

Germany is keen to keep upping the pace of its vaccination campaign even as new infections have sunk to their lowest level in months, pointing to the rise of the delta variant. Authorities believe it now accounts for more than half of new cases, and are keen to ensure that people get their second vaccine shots.

‘Only double-vaccinated protects well against delta,’ except in the case of the single-shot Johnson & Johnson vaccine, Spahn said.

As of Wednesday, Germany had given at least one shot to 55.1 percent of its population, and 37.3 percent were fully vaccinated. ‘That’s a good figure, but it’s still not enough,’ Spahn said.

Chancellor Angela Merkel, who is 66, recently received a second shot of Moderna’s vaccine after taking a first shot of AstraZeneca. 

Her spokesman said that was a conscious effort to encourage people not to be afraid if they are advised to get a mix of shots. 

Pictured: Vials of the Moderna vaccine in a German vaccine centre. The country's vaccine standing committee 'according to current study results,' the immune response from a mixture of AstraZeneca with an mRNA vaccine was 'significantly superior' to that from two doses of AZ

Pictured: Vials of the Moderna vaccine in a German vaccine centre. The country’s vaccine standing committee ‘according to current study results,’ the immune response from a mixture of AstraZeneca with an mRNA vaccine was ‘significantly superior’ to that from two doses of AZ

Germany frequently altered its approach to the AstraZeneca vaccine; first approving it for under 65s amid false concerns of its efficacy in older patients, then in early March walking back on the move by approving its use in over 65s.

On March 30, it was announced that the two-dose jab would no longer be offered to people under 60 and federal and regional health ministers agreed to give people under 60 who had been given a first dose of the AstraZeneca vaccine a different jab for their second dose.

Germany was not routinely offering jabs to those aged under 60 before the AstraZeneca ban took effect, meaning the group affected was only a small portion of the population – likely the clinically vulnerable and other risk groups who had priority.

The World Health Organization has previously said it cannot recommend switching vaccines between two doses as a protection against Covid-19, due to insufficient data showing the effects.

The concern over clots and mixed messages surrounding the vaccine are likely to have affected people’s willingness to take it in Germany and elsewhere in the EU.

As of June 30, Germany had fully vaccinated 37 percent of its population. By comparison, the UK has vaccinated 48.7 percent, the United States 46.6 percent and Israel almost 60 percent.

The recommendation comes on Friday as Angela Merkel backed down in a row over travel rules as she said in the ‘foreseeable future’ fully-vaccinated Brits will be able to visit Germany without having to quarantine.

Speaking alongside Boris Johnson at a press conference at Chequers, Mrs Merkel said Germany is ‘reviewing continuously’ its travel restrictions.

At the moment all UK travellers have to self-isolate on arrival in Germany for 14 days, with no exemptions.

But Mrs Merkel said that soon double-jabbed people ‘will be able to travel again without having to go into quarantine’.

Mrs Merkel last month had urged all EU member states to adopt Germany’s hardline approach to border rules.

Her comments today, following bilateral talks with Mr Johnson on the subject, pave the way for quarantine-free travel to open up across Europe in a massive boost for British holidaymakers. 

What is the difference between mRNA vaccines (Pfizer/Moderna) and vector-based vaccines (AstraZeneca/Johnson & Johnson)?

The major vaccines being rolled out in the UK and other western countries fit into two different categories: mRNA vaccines and viral vector-based vaccines.

Both the AstraZeneca and Johnson & Johnson vaccines are viral vector based, while both the Pfizer-BioNTech and Moderna vaccines are mRNA vaccines.

All except the Johnson & Johnson vaccine require two doses to be administered to person before they are considered fully immune to coronavirus, and initial advice said both jabs should be the same. 

But following studies, Germany is now recommending that people who were first given a dose of AstraZeneca (viral vector-based) should now be given one of the two mRNA vaccines for their second dose.

Viral Vector-Based Vaccines: AstraZeneca, Johnson & Johnson 

The viral vector-based vaccines use a harmless virus, called an adenovirus, as a delivery system to trigger the body’s immune response and to create antibodies to fight off SARS-CoV-2, which is the virus that causes Covid-19.

The adenovirus is not SARS-CoV-2 itself. Instead, its a different, harmless virus that has been manipulated to replicate the illness’ cause.

There are many different types of adenoviruses, which cause the common cold. For decades, they have been used to deliver instructions for proteins.

In Covid-19’s case, the vector virus delivers specific genetic instructions to cells produced by the body to produce a harmless piece of SARS-CoV-2. This is known as a spike protein. 

The cells then display this spike protein and the immune system triggers a response, producing anti-bodies to the spike protein to fight off what it thinks is an infection. 

Should the immune system later encounter the real SARS-CoV-2 and its spike proteins, it will already know how to defend the body against it.

mRNA vaccines: Pfizer, Moderna 

The Pfizer and Moderna mRNA vaccines are different. They use a novel technology that is yet to have been given wide-spread approval before the Covid-19 pandemic.

These vaccines use messenger ribonucleic acid (mRNA), a molecule that provides cells with genetic instruction for making proteins. These are needed for many of the body’s cellular functions, including immune defence. 

Scientists developed synthetic mRNA that is able to instruct the body’s cells to develop the same distinctive spike protein from SARS-CoV-2 that viral vector-based vaccines target.

Once the piece of protein is made, the cell breaks down the genetic instructions and gets rid of them both. The CDC has stressed that the mRNA never enters the central part of the cell where a person’s DNA material is.

This means that the vaccine does not affect or even interact with a person’s DNA in any way.

As with the viral-vector based vaccines, the immune system identifies the spike protein produced by the cells, building antibodies and thus triggering an immune response. The body will then be prepared in the case of SARS-CoV-2 infection in the future.

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