A recent study published in the journal ACS Central Science presents a new method to detect influenza infection by taste. This innovative taste-based sensor could cover the way for rapid, non-aggressive and low-cost detection of influenza, especially in the early stages of infection when no symptoms have yet appeared but they might be contagious. Understanding influenza and its global effect.
Influenza, commonly known as influenza, is a severe viral respiratory disease that continues to become an important burden to global health. Approximately 500,000 people die each year all over the world. The main subtypes that infect humans, which include influenza A strains, such as H1N1 and H3N2, and influenza B strains, known as Victoria and Yamagata. These viruses are classified based on the surface enzymes hemagglutinin (H) and neuraminidase (N), which play important roles, in how viruses attach and attack to host cells and spread between host cells.
Historically, influenza has caused the deadliest pandemics. The 1918-1920 Spanish flu infected about 1/4 of the world’s population, and the 2009 H1N1 influenza epidemic was most uncommon and unusual, affecting many more people under the age of 65. Although wide prevention efforts have significantly reduced infection rates during the COVID-19 pandemic, influenza remains seasonal and poses a serious risk to older adults, children, and people with weak immune systems.
More recently, influenza infections in animals and birds have been informed in the UK between 2022 and 2024, with H5N1 strains being the main variant, reminding us of the zoonotic nature of influenza and its capability and ability to cross species barriers.
Modern issues in influenza diagnosis
Precise and fast diagnosis of influenza remains a major challenge among experts. The most reliable method currently in use is the polymerase chain reaction (PCR) test, which can detect the hereditary material of the virus with high accuracy. However, PCR tests are costly, time-consuming, and often unavailable in areas with limited properties.
Serologic antibody tests might be unsuccessful in detecting asymptomatic or early infection cases, especially if antibody levels are still low. This diagnostic gap highlights the need for simpler, faster and more available testing tools that can detect infections before symptoms appear.
Inside the Research: A Breakthrough in Taste-Based Diagnosis
Researchers in a recent ACS Central Science study developed two unique sensors that detect influenza infection by responding to the viral enzyme neuraminidase, a key surface protein of the virus. These sensors were based on thymol, a compound with a characteristic taste that is chemically related in various forms to N-acetylneuraminic acid (Neu5Ac).
This design is amazing. Thymol is blocked and remains tasteless until viral neuraminidase is present. When this enzyme cleaves the glycosidic bond that connects thymol and Neu5Ac, the bond is broken and thymol is released, producing a detectable taste signal. This reaction fundamentally “tells” the user whether the virus’s neuraminidase is active or not, indicating an influenza infection. To test its effectiveness, the researchers compared the sensor’s response to neuraminidase from viral (H1N1) and bacterial (Micromonospora viridifaciens) sources. Only the viral enzyme successfully activated the taste signal, positive the selectivity and accuracy of the sensor.
Suggestions
To measure enzyme movement, saliva samples from PCR-established influenza patients collected during the 2017/2018 and 2022/2023 influenza seasons were examined. The results showed that the improved (methylated) sensor reacted specifically to viral neuraminidase in just 30 minutes and remained stable and inactive even in the presence of bacterial enzymes and uninfected saliva. The researchers decided that chemical modification of the Neu5Ac structure made the sensor highly selective for viral neuraminidase, an important advantage in unique influenza infections from other bacterial diseases. This study successfully verified the discovery of exact enzymes in saliva samples, but was unable to test them in vivo. This means we did not test whether participants themselves could detect changes in taste. The research team highlighted that future clinical trials are needed to authenticate this sensory feedback in real-world situations.
future potential
If this taste sensor proves effective in human trials/experiments, it could transform influenza diagnosis. Its simplicity and convenience make it particularly suitable for low-resource settings and public settings where traditional clinical trials are limited. Beyond influenza, similar chemical detection techniques could be applied to other viral infections, providing an entirely new method to analyses diseases using everyday human senses.
The researchers best summarized their findings:
> “We developed and chemically optimized neuraminidase-sensitive molecules that release palatable reporters when cleaved. We also demonstrated that these sensors can detect viral enzyme activity in patients’ saliva at physiologically relevant levels.”
conclusion
This revolutionary research provides an exciting viewpoint on the future of disease diagnosis. Taste-based influenza sensors that can detect infection through simple biological reactions could soon make early detection of influenza faster, easier, and more accessible than ever before. Although further clinical trials are still desirable, this study represents an inspired step in combination chemistry, human senses, and medical technology in the fight against infectious diseases.