No Need for Annual Updates as Next-Generation Flu Vaccine Becomes More Advanced

Efforts to create a flu vaccine that does not need updating every year are edging closer. Several researchers report significant progress towards an influenza universal vaccine, one that can protect against multiple virus variants at once and last longer than current seasonal vaccines.

Breakthrough from the Laboratory

A team of researchers at Stanford Medicine recently developed an experimental vaccine in the form of a nasal spray. This approach differs from conventional flu vaccines, which are typically delivered by injection and target particular strains each season.

In preclinical animal studies, the vaccine was able to activate two lines of defence, namely the innate and adaptive immune responses. This combination is considered important because it not only builds specific antibodies but also creates broader protection against a range of respiratory viruses. The results indicate protection lasting for months, not weeks.

Although still in the early stages and not yet widely tested in humans, the findings are viewed as a major step towards a vaccine that would not need annual updates.

Influenza viruses are notorious for rapid mutation. That is why seasonal flu vaccines are always adjusted to the strains predicted to be dominant each year. If predictions miss, vaccine effectiveness can decline.

The universal vaccine is designed with a different approach. Rather than targeting parts of the virus that mutate easily, scientists focus on relatively stable parts. A single vaccine could protect against many types of influenza A and B, and potentially confront new pandemic threats.

The World Health Organization regards next-generation influenza vaccines as potentially saving millions of lives over the coming decades. Flu is not merely a mild seasonal illness. Every year, hundreds of thousands die worldwide from influenza-related complications, particularly the elderly, young children, and people with comorbidities.

If a universal vaccine is truly effective and long-lasting, its impact would extend beyond individual health to the global health system. Production, distribution, and annual vaccination campaigns could be scaled down.

While early results look promising, researchers emphasise that the path to regulatory approval remains lengthy. Human clinical trials will be the main determinant, including safety, long-term efficacy, and potential side effects.

Researchers have not yet reached the point of having a universal flu vaccine ready for broad deployment. With ongoing research and strong global support, a realistic target could be reached within a few years.

Source: Stanford Medicine, World Health Organization

Although not as severe as COVID-19, influenza A (H3N2) subclade K, also referred to as the ‘super flu’, must still be avoided, especially by vulnerable groups.

That virus is known as Influenza D Virus (IDV) and has been found largely in cattle.

This virus is resistant to several common flu drugs. The high activity of polymerase D/HY11 is thought to be linked to its efficiency of transmission between mammals.

Influenza viruses, including the H1N1 strain, can remain infectious in raw milk stored at refrigeration temperatures for up to five days.

Find out the medical reasons why the influenza vaccine must be repeated every year. Understand virus mutation, waning antibodies, and the latest WHO recommendations 2026.