Amidst the ongoing challenges posed by seasonal viruses like influenza, colds, Respiratory Syncytial Virus (RSV), norovirus, and COVID-19, another highly common pathogen, adenovirus, is actively circulating across the UK. Often overlooked or mistaken for other illnesses, adenovirus has been identified by experts and public health bodies as a significant contributor to the current wave of sickness, frequently referred to as a "mystery virus" or a fast-spreading throat/respiratory bug.

Adenovirus is remarkably prevalent, with the NHS estimating that most individuals will experience at least one infection by the age of ten. As a constantly evolving virus, it mutates, allowing for multiple infections throughout a person's life. Unlike the seasonal peaks observed with influenza during colder months, adenovirus demonstrates a non-seasonal pattern, capable of being caught and transmitted year-round. Recent figures from the UK Health Security Agency (UKHSA) confirm its current widespread activity, as they monitor weekly positivity data for common respiratory viruses, including adenovirus, human metapneumovirus (hMPV), flu, COVID-19, and common colds.

Ian Budd, Lead Prescribing Pharmacist at Chemist4U, notes that many individuals infected with adenovirus are unaware of their condition, simply believing they are "under the weather." He clarifies key distinctions in symptoms: compared to a common cold, adenovirus is more likely to induce fever and conjunctivitis (pink eye), and its symptoms can persist for a longer duration. When contrasted with influenza, adenovirus infections typically result in less intense body aches and fatigue, and notably, there is no readily available vaccine for it. These viruses are not new; however, the simultaneous circulation of multiple pathogens has led to increased public awareness of symptoms and a rise in GP visits.

While adenovirus infections are most commonly observed in babies and young children, with current figures indicating five-year-olds as the most affected group, individuals of any age can contract the virus. Adenoviruses comprise dozens of types, with some preferring the respiratory tract while others impact the eyes or gut, leading to varied symptoms depending on the affected body part. Beyond typical cold-like symptoms, adenovirus can manifest as conjunctivitis, lung infections such as bronchitis and pneumonia, croup (characterized by a "barking cough" in children), ear infections, and gastrointestinal upset.

The virus is highly contagious and spreads rapidly in communal environments like nurseries, schools, hospitals, workplaces, and care homes. Symptoms typically emerge between two days and two weeks post-exposure. A crucial difference from colds is adenovirus's ability to survive on surfaces and objects for extended periods, meaning direct proximity to an infected individual is not always necessary for transmission. Furthermore, individuals can continue to "shed" the virus even after their own recovery.

Given its viral nature, adenovirus cannot be treated with antibiotics. Management primarily involves supportive care, including rest and ample fluid intake, with recovery typically spanning from a few days to a fortnight. Paracetamol is recommended for fever management, and humidifiers or saltwater nose drops may alleviate congestion. In more severe instances, particularly among very young babies, elderly individuals, or those with compromised immune systems, hospital treatment may be required.

Mr. Budd explains that respiratory viruses, including adenovirus, often spread more extensively during winter and early spring when people spend more time indoors. He suggests that the lifting of COVID-19 restrictions and reduced exposure to other viruses in recent years might have lowered community immunity, making people more susceptible. Emphasizing that adenovirus is not a new virus, he states it is simply appearing more frequently alongside other winter bugs. To mitigate the spread, the NHS advises prioritizing hygiene, including frequent handwashing and regular disinfection of surfaces and shared objects.