The Covid-19 pandemic has left us with one certainty: there will be others. The whole world is starting to prepareparticularly to avoid the mistakes made during the fight against the coronavirus and make our response more effective. And a key part of this response will rely on a reliable way to detect infected people early, so that they can isolate themselves and thus stop the spread of the virus.
However, the methods used during the previous pandemic were not perfect: either they were reliable but too slow and expensive, like PCR tests (which look for the presence of the virus's genetic material), or they were easy to do, but less reliable tests at the beginning of infection, such as tests antigenic (Who detect molecules of the virus). To find the right balance between reliability and trustworthiness, researchers at the University of Würzburg (Germany) have developed an approach that could be embedded in candy or chewing gum, allowing anyone to quickly perform their own screening… without having to stick swabs up their nose! They presented their method on the 1ster October 2025 in the magazine ACS Central Science.
When the infection tastes like thyme
“ If another pandemic strikes, we must be prepared to immediately screen entire cities, or even entire states or continents., the researchers state in their article. There is an urgent need for a first line of defense that is easy to produce, transport, and use. These tools could help quickly identify people at risk of infection so they can be isolated. This first step could then be confirmed by more reliable (but also slower and more expensive) tests.
With this goal in mind, they designed a simple detection method based on the ability of an enzyme in the influenza virus to cleave molecules. The protein in question is neuraminidase, which the virus uses to break certain bonds on the surface of cells, facilitating infection. The researchers used one of these bonds targeted by neuraminidase to create a molecule containing thymol, the compound that gives thyme its distinctive taste. Thus, when the virus is present, this molecular bond is broken by neuraminidase, releasing the thymol and therefore its characteristic flavor.
The saliva of infected people transforms this molecule and releases the taste of thyme
Researchers tested this molecule with saliva from people suffering from the flu, showing that the concentration of the virus in this saliva was sufficient to produce the reaction that releases the flavor of the herb. This virus sensor responded only to the neuraminidase of viruses and not to that of bacteria, avoiding potential false positives caused by the individual's oral microbiota. Their molecule would therefore be specific, and only about 10 mg would be needed to produce a sufficient amount of thymol for the tongue to detect this change in taste.
In terms of safety, they tested their molecule on human and mouse cells, showing that it caused no cellular damage. However, this will need to be confirmed by further studies. And, in terms of stability, the molecule is said to withstand almost any climatic condition (except above 50°C) for at least four weeks, which would facilitate its transport and storage.
Spicy, bitter, or colored chewing gum, depending on the illness
The researchers explain that their molecule could be modified for certain cases where the thyme flavor isn't strong enough, for example, if the infection weakens the sense of taste. In that case, a more bitter flavor (like the one used in cleaning products to prevent children from accidentally drinking them) could do the trick. And if the illness... to lose taste (As was the case with Covid for some infected individuals), a dye could be added, which would only be released in the presence of the virus. With a foul taste and a blue tongue, it would be difficult to miss an infection!
However, it remains to be seen whether these laboratory results are confirmed in real-world conditions, and whether infected individuals will actually detect the taste released by the molecule during infection. If so, expect to receive your share of tests during the next pandemic: we may be in lockdown, but we'll have free chewing gum… and that's great news for those who like thyme.
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