Taste-based flu test enables rapid diagnosis

Influenza is one of the most dangerous infectious diseases worldwide, claiming around half a million lives every year — yet the diagnostic options available to date can be expensive, complicated to use and simply unavailable in many poorer regions of the world. Now, researchers from the University of Würzburg have developed a novel self-test for influenza — and it’s all based around taste.

Described in the journal ACS Central Science, the diagnostic tool consists of the sensor molecule thymol — a natural substance found in thyme, among other things — and a virus-specific sugar building block, both of which could be incorporated into confectionery such as chewing gum or lollipops. When the tool comes into contact with active influenza viruses in the saliva of infected people, these release the thymol, creating a clearly recognisable taste in the mouth. In the mouths of non-infected individuals, meanwhile, nothing would happen.

“Instead of relying on expensive and complicated testing procedures, we use the natural human sensory system — taste — as a tool for the early detection of infections,” explained team leader Lorenz Meinel.

“This strategy opens up new possibilities for the early detection and control of influenza worldwide.”

Anyone could use the tool anytime, anywhere, without the need for a laboratory, electricity or medical personnel. Furthermore, the principle is flexible, as both the flavour carrier and the recognition component can be adapted. For example, the system can be equipped with sweet, bitter or salty flavours — even child-friendly ones. It can also be transferred to different pathogens.

“For other infections, for example, the virus-specific sugar component could be replaced by a bacteria-specific peptide; the underlying functionality would remain the same,” Meinel explained. The method thus opens up new possibilities for low-threshold diagnostics of viral and bacterial infections — from influenza to future pathogens that are not yet known today.

The researchers believe their tool would be particularly suitable for critical locations such as schools, nurseries and retirement homes — especially in poorer countries — where it is important to contain outbreaks of infection. To this end, they are currently collaborating with FlareOn Biotech, a startup founded in 2024 by the University of Würzburg, on making the diagnostic system suitable for mass production. The development process is expected to take around four years.

As soon as an application is available, the researchers would like to ask all users to voluntarily record positive influenza test results using a smartphone app. This data could provide a previously unattainable online overview of the situation, enabling the spread of influenza viruses to be tracked in real time. Artificial intelligence could then also be used to predict where epidemics or pandemics might develop, enabling the World Health Organization, governments, local authorities and even individuals to take precautionary measures at an early stage.

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