Health Brief: Booster shots. Not if, but when

Subscribe to EURACTIV's Health Brief, your weekly update on all things healthcare in Europe.

While some EU countries are already approving the COVID-19 booster doses, the bloc’s main health agencies have been more cautious so far, saying that there is no urgent need for additional shots in the general population.

But according to Edoardo Colzani, vaccine-preventable diseases expert at the EU’s infectious disease agency (ECDC), the ‘big question’ at the moment is when the booster will be needed.

Booster doses are given to vaccinated people who have completed their primary vaccination with the aim of restoring protection after it has waned. No booster has been authorised by the European Medicines Agency (EMA) at the moment, but an evaluation of the use of a third dose of the vaccine developed by BioNTech/Pfizer is currently ongoing.

In the meantime, another mRNA platform vaccine, Spikevax – Moderna’s jab – submitted a conditional marketing approval for the evaluation of its booster dose which formally started on Monday (27 September), the EMA announced.

“We are waiting for more solid evidence about the safety and the effectiveness of the booster,” ECDC’s Colzani told EURACTIV.

An expert review recently published in The Lancet journal and conducted by an international group of scientists concluded that vaccine efficacy against severe COVID – even for the delta variant – is so high that booster doses for the general population are not appropriate at this stage in the pandemic.

The lead author, Ana Maria Henao Restrepo from World Health Organisation (WHO), said that “taken as a whole, the currently available studies do not provide credible evidence of substantially declining protection against severe disease, which is the primary goal of vaccination.”

Despite that, some EU countries, like Hungary, already started giving a third dose to anyone who received full vaccination at least four months ago.

When will we know?

Colzani said that the time for a booster vaccination will come: “We can expect that at some point this will be needed. But if you ask me if it’s one month, five months, or eight months, or more, it is difficult to tell at this stage.”

The question is hard to answer for several reasons. Firstly, the level of antibodies cannot be a single indicator for a potential booster dose.

Protection against severe disease is mediated not only by antibody responses, which might be relatively short-lived for some vaccines but also by memory responses and cell-mediated immunity, which are generally longer-lived.

So, If boosters are required in the end, there will be a need to identify specific circumstances where the benefits outweigh the risks, as noted in Lancet’s review.

Aurelija Žvirblienė, chief research scientist and head of the department of immunology and cell biology at Vilnius University’s Institute of biotechnology in Lithuania, told EURACTIV that “memory cells are the basic principle of vaccines”.

She added that “cell-mediated immunity is very important when fighting infections […] but it can only be measured in scientific labs”.

Not too early, not too late

This is something that the authors of Lancet’s review also noted: “Even if levels of antibodies in vaccinated individuals wane over time, this does not necessarily predict reductions in the efficacy of vaccines against severe disease.”

Therefore, Colzani pointed to clinical indicators: “It may require that we have to wait to see further signals from the observational studies that are ongoing and, ideally, from the trials”.

This recalls what Žvirblienė said – the best indication that there is a need for an additional dose is when people who have received a full vaccination cycle start falling heavily ill and need hospitalisation.

Camilla Foged, a professor leading the research group Vaccine Design and Delivery at the University of Copenhagen, told EURACTIV that waning immunity can already be seen in Denmark as “there are more breakthrough infections”.

The third dose, she said, “should not come too late and should not be given too early”. “Somehow we have to wait to see the data before we give it a third dose in a mass vaccination program,” Foged said.

Focus remains on unvaccinated

ECDC’s Colzani said that preparing for the booster is important as the current COVID situation is “a very dynamic landscape.” While highlighting the need for constant monitoring of the situation, he stressed that “the main focus should remain on vaccinating the unvaccinated people.”

He added that despite some breakthrough infections in vaccinated people, the vast majority is still occurring among the unvaccinated population, particularly severe infections leading to hospitalisation and death.

Colzani also explained that it is important to maintain a low circulation of the virus in the community and in high-risk settings through appropriate measures.

“Therefore, the impact of any waning of the immunity will be much lower because people don’t get exposed to the virus as much,” and this would make the question of a booster “less pressing,” he concluded.


Subscribe to EURACTIV’s Health Brief, where you’ll find the latest roundup of news covering Health from across Europe.

-On Monday (27 September) Stella Kyriakides addressed the European Parliament’s health committee (ENVI) on the new Health Emergency preparedness and Response Authority (HERA), which is to become a key actor in strengthening Europe’s ability to prevent, detect, and rapidly respond to cross-border health emergencies.

HERA will become fully operational by early 2022 but the European Parliament was not included in the creation of this new authority. The EU’s health boss had to reassure MEPs there was no intention to exclude the Parliament. But lawmakers weren’t impressed. “Why is the European Parliament not given a seat at this negotiation table?” asked Swedish socialist MEP Jytte Guteland.

In her opening remarks, Kyriakides rushed to assure the MEPs that there was no intention to exclude Parliament. “This was never about exclusion. This was about moving as quickly as possible in a flexible way and for it to be operational immediately,” Kyriakides said.

She added that MEPs will have a seat on HERA’s board so that the Parliament “will be fully addressed, fully informed, fully able to have a position on all developments” and also get to vote on its budget. She added that in 2025 an in-depth review of HERA will be conducted and “what needs to be changed will be changed”.

-The European Parliament’s budget committee has adopted their position on the 2022 EU budget, which includes the reinforcement of the EU4Health programme, with an additional €80 million to build up a strong European Health Union and strengthen the resilience of national health systems.

-On Tuesday (28 September), the Commission launched a public consultation into the pharmaceutical strategy, the EU’s plans to overhaul the current legislation on medicines.

-Sanofi announced on Tuesday (28 September) that it was ending the development of its vaccine against the m-RNA coronavirus. According to the French group, the vaccine arrived on the market too late and was outpaced by Pfizer/BioNTech and Moderna.

Sanofi had been working since March 2020 with Translate Bio on this vaccine, and even bought this American biotech company at the beginning of August for some €2.7 billion. As a result, Sanofi will not develop a phase 3 for this vaccine, as “there is no public health need for another messenger RNA vaccine,” Thomas Triomphe, vice-president of Sanofi’s vaccines branch told the AFP.

-Last week the Commission has signed a joint procurement framework contract with the pharmaceutical company Eli Lilly for the supply of a monoclonal antibody treatment for coronavirus patients, which is currently under rolling review by the EU’s medicine agency (EMA).

– On Monday (27 September,  the Commission awarded grants to 20 Member States totalling €95 million to purchase COVID-19 diagnostic tests to facilitate the delivery of the EU Digital COVID Certificate.

-This week, EURACTIV looked into co-infection risk of COVID and other respiratory pathogens as, combined with the increasing number of immunocompromised people exposed to COVID, can create a double whammy that cannot be overlooked.

In our very first Health Brief last week, you will have read about a legislative proposal for amending the In Vitro Diagnostics (IVD) Medical Devices Regulation in October, which aims to avoid shortages of some critical IVD devices.

As we received a number of requests for clarification from our readers on this, we contacted the Commission for more information on this legislative proposal. An EU official replied that they have received calls from both the Council and MEPs, as well as stakeholders expressing concerns about the readiness of the system to transfer to the new legal Regulation (IVDR) and asking for legal action to address these concerns.

The Commission said that they share the concerns, which mainly relate to the limited notified body capacity under IVDR and limited preparedness of some manufacturers. COVID-19 has highly impacted the sector. In light of this, the Commission is planning to put forward a targeted proposal to smoothen the transfer from the current Directive to the new Regulation. The proposal does not seek to amend IVDR in substance.

Today (28 September) is also international safe abortion day, celebrated to ensure that legal and safe abortion is a fundamental right. The day was anticipated by the historical referendum in San Marino, who voted in favour of legalising abortion. EURACTIV’s Viola Stefanello digs deeper into the current situation when it comes to the right to abortion in Europe.

This week, there is the European Health Forum Gastein (EHFG), a key policy platform, bringing together politicians, senior decision-makers, community members, and experts in the field of health and beyond.

On Monday’s (27 September) press point for the launch, the discussion on Europe’s place in a new global order took place. Hans Kluge, Regional Director for Europe, World Health Organisation emphasised the need to strengthen the international health architecture, advocated for more international cooperation

But Ilona Kickbusch, Founding Director Global Health Programme at Graduate Institute Geneva, warned against regions competing against each other and called for a new vision of multilateralism, supported by a stronger WHO and new collaborative frameworks such as the European Health Union. “All parts of the European Union must be moved forward together to address the fragmentation and the decoupling in global health,” she said.

On Tuesday (28 September) the World Health Organization and partners launched the first-ever global strategy to defeat meningitis – Defeating meningitis by 2030: a global Roadmap. By 2030, the goals are to eliminate epidemics of bacterial meningitis – the most deadly form of the disease – and to reduce deaths by 70% and halve the number of cases.

“It is time to tackle meningitis globally once and for all –by urgently expanding access to existing tools like vaccines, spearheading new research and innovation to prevent, detecting and treating the various causes of the disease, and improving rehabilitation for those affected,” said Dr Tedros Adhanom Ghebreyesus, WHO Director-General.

On Tuesday (September 28) Valneva SE and Pfizer Inc. announced further positive Phase 2 results, including booster response, for Lyme disease vaccine candidate VLA15. “These positive results of the Phase 2 VLA15-202 study represent another important milestone in the development of VLA15, and we look forward to continuing our development efforts in our quest to potentially protect people from Lyme disease in the future,” said Kathrin Jansen, Senior Vice President and Head of Pfizer Vaccine Research and Development.

VLA15 is the only active Lyme disease vaccine candidate currently in clinical development and covers six serotypes prevalent in North America and Europe. The vaccine candidate uses an established mechanism of action that targets the outer surface protein of the disease-causing bacteria.

In Slovenia, vaccine hesitancy persists. Slovenia has been among the EU’s laggards regarding vaccination uptake. The sentiment is prevailing despite a Covid pass mandate that requires individuals to be vaccinated, recovered or tested to access virtually all services. Sebastijan R. Maček | STA

Slovaks’ fear of vaccine is higher than solidarity. The reason for the low vaccination rate in Slovakia is mainly the fear of the vaccine, a new study published by the Slovak Academy of Sciences shows. In some cases, this fear can be stronger than solidarity with other people and the fear of getting the disease. Michal Hudec |

Masks to soon only be required in Portugal’s high-risk, crowded places. The use of masks will only be required on public transport, in supermarkets, homes, hospitals, entertainment venues and big events from 1 October in Portugal, once the third phase of lifting measures announced Thursday kick in. Isabel Matos Alves and Lucília Tiago | 

Au revoir, masks! Wearing a mask will no longer be compulsory in schools from 4 October in departments where the incidence rate has been below 50 per 100,000 inhabitants for the past five days, a government spokesman has announced. The same rules will apply to establishments open to the public like concert halls and nightclubs, he added. Clara Bauer-Babef |

Slovak health ministry silent over Sputnik’s third dose. The health ministry announced that the 20,000 people who received the Sputnik vaccine in Slovakia will be given Pfizer as a third dose. Michal Hudec |

Italy’s far-right Lega split over mandatory health pass. A decree making it mandatory for workers in the private and public sectors to have a health pass indicating that they are vaccinated, tested negative within the past 48 hours or recovered from COVID-19 was only backed by 69 of 132 Lega MPs, although the party is part of the ruling coalition that decided in favour of mandating health passes in the first place. Viola Stefanello |

27 September – 1 October | European Health Forum Gastein

27 September – 3 October | European Biotech Week 2021

27 September – 1 October | European Diabetes Forum annual meeting

30 September | Webinar on Europe’s beating Cancer Plan and the EU mission on cancer organised y SIOPE-MAC.

4 October – 7 October | European Parliament’s plenary

Subscribe to our newsletters