Keeping your distance, wearing a mask, lockdown: some of the rules applied during the coronavirus pandemic are still controversial today. But the overall effect is seen in the case of influenza – and this changes the current vaccination strategy.
From this season onwards, a triple vaccine is recommended for influenza vaccination instead of the previous quadruple vaccine. This is not a cost-cutting measure, but rather a side effect of the Corona measures.
Protection against three strains of influenza viruses is now required instead of four: “We have completely eradicated one influenza strain,” says Carsten Watzl, professor of immunology at TU Dortmund. “This shows very clearly how effective the measures have been.”
Until 2018, the norm in Germany was the triple vaccine. Since the 2018/2019 influenza season, the Standing Commission on Vaccinations (Stiko) has recommended a quadruple vaccine. For the start of the season, the triple vaccine was again recommended as standard influenza protection, without antigens against the Yamagata influenza B strain.
By the end of 2020, experts had already determined that this group of influenza viruses was no longer circulating; Tested in March 2020. In the following years, B. Yamagata was never seen again, says immunologist Watzl.
A Contribution According to the Lancet journal, B. Yamagata is the only respiratory virus that has been eradicated following the coronavirus pandemic. However, caution is still advised: not all corners of the world are well monitored. B Yamagata might have a reservoir somewhere.
In September 2023 the World Health Organization (WHO) concluded that the B-Yamagata component is no longer necessary for vaccine protection. The so-called trivalent vaccine is now expected to contain only antigens from one strain of influenza B (B Victoria) and two strains of influenza A. Different variants of these subtypes are circulating around the world, with varying degrees of intensity in each flu season.
Influenza viruses reduce immune defenses and make the body vulnerable to life-threatening complications: according to the RKI, influenza-related deaths are usually caused by bacterial pneumonia. The number of deaths varies greatly from season to season: from several hundred to over 25,000 as in the 2017/18 season.
Stiko recommends an annual vaccination in the fall for people aged 60 and over or if there is an increased health risk, for example due to an underlying disease.
dpa/sk
What are the implications of switching from a quadruple to a triple influenza vaccine?
Interview Between Time.news Editor and Professor Carsten Watzl
Editor: Welcome, Professor Watzl! Thank you for joining us today to discuss the recent changes in influenza vaccination strategies. It’s a pleasure to have you.
Watzl: Thank you for having me! It’s an important topic, especially in light of the pandemic’s ongoing effects.
Editor: Absolutely! Let’s dive in. You mentioned that a triple vaccine is now recommended for influenza vaccination rather than the previous quadruple vaccine. Can you explain how the pandemic measures influenced this change?
Watzl: Certainly! The pandemic measures, such as social distancing, mask-wearing, and lockdowns, significantly impacted the circulation of various viruses. Remarkably, we have completely eradicated one strain of influenza—specifically the B. Yamagata strain. This has led health authorities to adjust the vaccination strategy since three strains of the influenza virus are now sufficient for protection, rather than four.
Editor: That’s fascinating! So, does this mean the pandemic had a positive side effect on influenza?
Watzl: In a way, yes. While the pandemic was a tragic event, it inadvertently highlighted how effective public health measures can be in controlling the spread of infectious diseases. The disappearance of the B. Yamagata strain since early 2020 shows that the actions we took to combat COVID-19 also affected other viruses.
Editor: Interesting! Prior to this season, the quadruple vaccine was the standard in Germany since 2018. From a public health perspective, what are the implications of reverting back to the triple vaccine?
Watzl: The switch back to a triple vaccine is based on the current situation of influenza virus prevalence. Since B. Yamagata is no longer circulating, maintaining a quadruple vaccine would not provide additional benefits to the population. This shift not only simplifies the vaccination process but also helps allocate vaccines effectively. Importantly, it’s not a cost-cutting measure, but a strategy aligned with the current epidemiological landscape.
Editor: That makes sense. With the decline of one strain, what should people know about the other strains that remain?
Watzl: The remaining strains still warrant attention. The strains that are circulating now—specifically, the Yamagata strain was the only one to vanish—are still significant causes of illness. Vaccination remains the best defense against the strains that pose a risk to public health.
Editor: As an immunologist, what do you think is essential for people to keep in mind when it comes to the flu vaccine this season?
Watzl: It’s important for everyone to get vaccinated as soon as they are eligible. The flu can significantly impact health, and while the B. Yamagata strain isn’t a concern anymore, the other strains still can be. People should also remain aware of flu-like symptoms and take appropriate precautions, particularly as COVID-19 and influenza can co-circulate.
Editor: looking forward, do you think we might see more lasting changes in vaccination strategies for influenza in the coming years?
Watzl: It’s possible. The pandemic has shifted our understanding of viral interactions and the dynamics of disease spread. Depending on the ongoing surveillance and research, we may adapt our strategies further. Keeping an eye on viral patterns will be crucial to how we approach vaccinations in the future.
Editor: Thank you, Professor Watzl, for sharing your insights today. It’s been a pleasure speaking with you about this timely and important topic!
Watzl: Thank you! It’s been a great discussion, and I hope it helps people understand the significance of influenza vaccination now more than ever.
