New COVID-19 Variant ‘Stratus’ Emerges with Unique Symptoms

A new variant of COVID-19, named Stratus, is spreading rapidly across the globe, distinguished by a unique early symptom that sets it apart from other strains. First detected by health officials in January 2025, Stratus appears in two forms: XFG and XFG.3. By June of the same year, the World Health Organization (WHO) included XFG on its monitoring list due to its swift global transmission.

Typically, COVID-19 symptoms align with those of other respiratory illnesses, such as fever, cough, and a runny nose. However, Stratus exhibits a distinctive early sign: a hoarse or raspy voice, which may appear before more common symptoms develop. This particular symptom can easily be overlooked, complicating early detection. In addition to the hoarse voice, medical professionals have reported other symptoms associated with the new variant, including sore throats, nasal congestion, digestive issues, and extreme fatigue.

The Stratus variant gained significant momentum in the United States during the summer of 2025, eventually becoming the prevailing strain. A surge in cases was also attributed to another variant known as Nimbus. Dr. Gareth Nye from the University of Salford stated, “In most ways, it’s almost identical. However, people with this version tend to get very sore throats and a hoarse voice, compared with the other more general symptoms like cough, temperature, and aches.”

As children return to school, illness rates often spike due to close contact and varying hygiene practices. Dr. Nye noted that the Stratus variant can partially evade the immune system, making previous vaccinations less effective. He emphasized the importance of staying current with COVID-19 vaccinations.

Stratus was first identified in Southeast Asia in January 2025 and made its way to the U.S. by March. By mid-September, it had emerged as the dominant variant in U.S. wastewater samples. By the end of September, estimates indicated that Stratus was responsible for approximately 85% of COVID-19 cases in the country.

Despite the emergence of Stratus, the WHO has assured the public that currently approved COVID-19 vaccines are expected to remain effective against severe illness caused by this variant. Dr. Peter Chin-Hong from the University of California, San Francisco, voiced concerns about the broader range of symptoms associated with Stratus. He remarked, “There’s a little bit more sore throats with some people, particularly older adults who didn’t get vaccinated last year. It’s more transmissible, so we expect that a lot of people will get it.”

Health officials emphasize that with children returning to school, even minor symptoms such as a sniffle could indicate COVID-19. As public anxiety rises regarding this new variant, GOV.UK reassures that virus mutation is a normal process. They are actively collecting data to better understand and combat the evolving virus.

“It’s normal for viruses to mutate and change,” the blog states. “As more data becomes available on these variants, we’ll have a better understanding of how they interact with our immune systems and how to optimize our protection while keeping the most vulnerable safe.”

The most crucial step for eligible individuals remains to get vaccinated when due, ensuring not only personal health but also the well-being of the community at large.