Five years after the peak of the global pandemic, the world continues to grapple with the evolving landscape of Covid-19. The latest twist comes from the United Kingdom, where a new strain dubbed ‘Stratus’ has rapidly become the most prevalent variant, accounting for nearly a third of all cases in England. What sets Stratus apart is not just its speed of spread, but a unique and unexpected symptom, a hoarse voice.With experts warning of increased immune evasion and the World Health Organization (WHO) keeping the strain under close surveillance, the emergence of Stratus and its sub-variants XFG and XFG.3 is a timely reminder that the fight against Covid-19 is far from over.What Is New Covid Variant Stratus?First identified in January 2025, the Stratus strain—officially classified under the XFG lineage and its subvariant XFG.3—has become the most common form of COVID-19 in England. According to the UK Health Security Agency (UKHSA), the XFG.3 variant currently accounts for a greater proportion of cases than any other single strain, with Stratus overall making up roughly 30% of infections in the region.The World Health Organization (WHO) has designated Stratus as a "variant under monitoring," a classification that signals the need for heightened genomic tracking, though it has emphasized the variant currently poses a low risk to global public health.What sets Stratus apart from prior variants, particularly its Omicron predecessors, is a peculiar but increasingly common symptom: a hoarse or raspy voice, an anomaly not prominently associated with COVID-19 strains before.Dr. Alex Allen, Consultant Epidemiologist at UKHSA, emphasizes that while viruses naturally mutate over time, the Stratus strain’s unique symptom profile and rapid spread warrant careful monitoring.Stratus is not just another offshoot of Omicron; it is what scientists call a “recombinant” or “Frankenstein” variant. This means it emerged when an individual was infected with two different Covid strains simultaneously, resulting in a new hybrid lineage. Such recombination events are rare but can lead to variants with novel characteristics—including changes in transmissibility, immune evasion, and symptomatology.Reports from the World Health Organization indicate that Stratus is showing signs of additional immune evasion compared to other strains. This means it may more effectively bypass existing immunity from previous infections or vaccinations, contributing to its rapid spread.How Widespread Is Stratus Globally?As of June 22, 2025, Stratus has been detected in 38 countries, according to the World Health Organization. In addition to its prevalence in the UK, it is showing a slow but steady increase in several regions across Southeast Asia and Europe, and health authorities in the United States are closely monitoring imported cases.The WHO noted that several nations have reported rising case counts and mild upticks in hospitalization rates alongside increased detection of XFG. However, current evidence does not indicate that Stratus causes more severe illness or higher mortality than other circulating Omicron variants.As of late June 2025, Stratus accounted for 22.7 percent of global Covid-19 cases, according to the WHO. It has been detected in 38 countries, reflecting its global reach. The UK remains the epicenter, but rising case numbers have also been reported in South-East Asia, Australia, and several U.S. states.The true scale of the spread, however, is difficult to measure. With widespread reductions in Covid-19 testing compared to the height of the pandemic, many cases may go undetected or unreported. This underlines the importance of genomic surveillance and international cooperation in tracking emerging variants.Recognizing the Symptoms of Stratus StrainWhile the hoarse voice is the most distinctive symptom reported with Stratus, health authorities have not yet listed any other unique symptoms for this variant. The classic symptoms of Covid-19—including fever, persistent cough, loss of taste or smell, fatigue, headache, and sore throat—remain common.The NHS continues to advise the public to watch for:High temperature or shiveringNew, continuous coughShortness of breathLoss or change in sense of smell or tasteFeeling tired or exhaustedAching bodyHeadacheSore throatBlocked or runny noseLoss of appetiteDiarrheaNausea or vomitingThe emergence of a hoarse voice as a prominent symptom highlights the need for ongoing vigilance and public awareness, especially as new variants may present in unexpected ways.Is Stratus Variant More Dangerous?So far, there is no evidence that Stratus causes more severe disease than previous variants. Dr. Alex Allen, Consultant Epidemiologist at UKHSA, stated that the agency continues to monitor the situation closely, adding, “It is normal for viruses to mutate and change over time.”Dr. Allen also emphasized that COVID-19 vaccines in use remain effective against Stratus and its subvariants. While Stratus shows signs of “immune evasion,” experts clarify this doesn’t mean existing immunity—whether from vaccination or prior infection—is rendered useless. Instead, it may suggest slightly reduced protection against infection, not against severe illness.The UK and many other countries continue to offer seasonal COVID-19 booster doses, especially for vulnerable groups. In the UK, the NHS is currently offering the vaccine to:Individuals aged 75 and abovePeople aged 6 months to 74 with weakened immune systemsResidents in adult care homesThe rationale remains the same: over time, vaccine-induced immunity wanes, and booster doses "top up" protection, reducing the risk of severe symptoms, hospitalization, and death.As of now, there is no need for a new vaccine targeting Stratus, but virologists remain vigilant. The adaptability of mRNA vaccine platforms allows manufacturers to update formulations quickly, should a variant emerge that significantly escapes immunity.While the Stratus strain doesn’t appear to be more deadly or vaccine-resistant, it’s a clear reminder that COVID-19 is not behind us. The virus continues to mutate, and new symptoms—like a hoarse voice—may require clinicians and patients to adjust their awareness of what infection might look like.Public health experts advise individuals to stay up to date with vaccines, test if symptomatic (especially if vulnerable or in contact with high-risk individuals), and continue practicing good hygiene, particularly in crowded indoor spaces.