During the annual autumn flu and cold season, many ponder whether to get vaccinated against the flu. Each year, a new vaccine is necessary due to the ever-changing flu viruses that evade immunity. The vaccination is especially vital for at-risk groups, such as the elderly and those with pre-existing conditions, as they face higher risks of severe illness. Despite a pandemic-related increase in vaccinations, Germany’s rates remain below EU targets, with possible developments in mRNA vaccines on the horizon for improved adaptability.
As the annual flu and cold season approaches in autumn, many people wonder: Should I get vaccinated against the flu? Am I even allowed to? And why is there a new vaccine each year?
Autumn is vaccine season—especially when it comes to flu vaccinations. However, before opting for immunization against influenza viruses, it’s essential to address several questions.
Why is there a new flu vaccine every year?
Flu viruses are constantly changing. This evolution is necessary for them to evade their host’s immune system. Even individuals who have built a strong immunity through numerous infections and vaccinations can find themselves vulnerable to new strains that slip past their defenses and cause an infection. This immunity often helps prevent severe illness caused by these new viruses, even if it does not stop the infection outright.
Around two-thirds of influenza infections are mild or asymptomatic, while one-third may lead to severe flu with significant symptoms. This can be particularly dangerous for older adults or those with pre-existing health conditions, making vaccination crucial for these groups and recommended by the Standing Committee on Vaccination (Stiko).
The Association of General Practitioners advises at-risk groups to renew their vaccination protection.
How is it determined which variants to vaccinate against?
Laboratories worldwide continuously monitor circulating flu viruses and estimate which variants might become predominant. They then submit this data to the World Health Organization (WHO).
Typically, by February, the WHO predicts which four virus strains are likely to dominate the upcoming flu season in the Northern Hemisphere. This foresight provides vaccine manufacturers the opportunity to adjust their vaccines accordingly.
These vaccines usually already have approval and do not require extensive new trials, although their safety and efficacy are continually monitored post-approval. In Germany, it is common to vaccinate against all four of the strains predicted as dominant by the WHO.
Who is recommended to receive the vaccine?
This year, Stiko recommends the flu vaccine primarily for at-risk groups: individuals over 60, pregnant women, and those with specific underlying health conditions, as well as anyone who, professionally or personally, has significant contact with these high-risk patients. Additionally, individuals at an increased risk of infection, such as those working closely with large groups of people, should consider vaccination.
About half of the children born in 2016 are reportedly not fully vaccinated, according to the Techniker Krankenkasse.
The absence of a recommendation from Stiko for other demographic groups does not imply they should avoid vaccination. Although infections in healthy children, teenagers, and adults typically present mild symptoms with minimal risk of severe illness—which is why Stiko does not recommend vaccination for them—these individuals can still vaccinate themselves to reduce the likelihood of becoming infected or infecting others.
How many people get vaccinated?
In a European context, relatively few people in Germany receive the flu vaccine. Although vaccination rates surged during the pandemic, they are now declining again. In nearly all observed population groups, vaccination rates fall below 50% on average. Notably, vaccination rates are considerably higher in the new federal states than in the old ones.
The European Union has set a target vaccination rate of 75% for those over 65 years old. According to Eurostat, Germany fell short of this goal in 2022, achieving only around 43%. Comparatively within Europe, this places Germany roughly in the middle, with only Denmark, Portugal, and Ireland meeting the target rate. The Paul-Ehrlich Institute released about 20 million vaccine doses this year, significantly fewer than in previous years.
Despite all recommendations, fewer children are being vaccinated against the HPV virus.
How effective are the vaccines?
The effectiveness of flu vaccines is difficult to determine due to ongoing changes in both viruses and vaccines. Effectiveness largely hinges on the accuracy of WHO’s predictions, along with individual factors. Notably, vaccines tend to be less effective for older individuals. Therefore, the Robert Koch Institute (RKI) recommends high-dose vaccines for those over 60.
Even post-implementation, gauging vaccine effectiveness is challenging. The RKI estimates that flu vaccines are less effective compared to other vaccines, with effectiveness levels ranging from 20% to 60% during the 2010s. Nevertheless, vaccinations have been proven to lessen the severity of flu symptoms, even if they cannot prevent infection altogether.
While many understandably feel hesitant about vaccinations, this poses significant risks for at-risk groups.
What side effects can occur?
Generally, flu vaccines are