This autumn, having finally passed through the worst of the COVID‑19 pandemic, a related, troubling threat is showing strong indications of spreading throughout the Northern hemisphere: a potential ‘tripledemic’ of COVID‑19, respiratory syncytial virus (RSV) and the flu (influenza A/B).

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While the population was in isolation for much of 2020‑2021, restricted interactions not only helped curb the levels of COVID‑19, but also led to fewer cases of the common cold, the flu, and RSV. While RSV often causes mild symptoms akin to a cold, it can have dangerous consequences for more vulnerable populations. In the US, hospitalisations for the flu have also been reported to be at higher levels now than any time since 2010. RSV infections are already causing significant strain to US hospitals in multiple states.

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Children who haven’t been exposed to these viruses in the first few years of their life, due to social distancing throughout the COVID‑19 pandemic, are also more immunologically naïve than in previous years. This means that their natural levels of exposure may have essentially been delayed, leaving them more susceptible to infections at an older age than would normally happen.

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For us adults, the ‘asymptomatic boosting’ that might normally happen from exposure to viruses has also been lower, which means that our blood antibody levels, protecting us from such infections, may have generally waned. This is a phenomenon that many researchers, including my department at Imperial College, are currently investigating.

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In terms of recent RSV infections in the UK, the UK Health Security Agency suggests that 7.4% of the country’s population is currently suffering from RSV, including one‑third of those under five years of age. RSV can result in bronchiolitis which accounts for about one in six hospital admissions for children in the UK.

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Flu infections have also risen following the COVID‑19 lockdown, and recently, it was estimated that approximately two million people in the UK have COVID‑19. A rise in such infections has also been reported in Australia and the US. A March 2022 Lancet article also reports that around 8% of hospitalized COVID‑19 patients have also been found to be co‑infected with flu, RSV, or adenoviruses. Increased case numbers in other European countries like France, Germany, Sweden and Finland are also expected for COVID‑19 or the flu.

 

With the risk of a ‘tripledemic’ at our doorstep, having a rapid and accurate diagnostic that can test for multiple pathogens lets people (i) understand which viruses they might have or are carrying if they are symptomatic for a respiratory infection, and (ii) helps them decide whether self‑isolation is required to help prevent the spread of the infection(s) to others. ProtonDx’s Dragonfly can play an important role here, with the whole process, from sample‑to‑result, completed in under 30 minutes with minimal effort. Developed for use at the point‑of‑need, for example, in healthcare settings, everything you need is provided in a single‑use disposable detection kit for use with the Dragonfly platform. Our focus is on supporting early detection to prevent the spread of infectious disease, and we hope that our technology will make a difference and help individuals have a healthy winter ahead.