New COVID Variant Stratus: Symptoms, Severity, and What to Know

If you’ve recently found yourself with a scratchy voice and a mild cough, you may be wondering if it’s just a cold or something more. Health officials in the UK are closely monitoring a new COVID-19 variant called Stratus (XFG) that’s spreading rapidly and causing a distinct hoarseness.

Dominant strain: Stratus (XFG) ·
Spread: Rapidly increasing in the UK as of Sept 2025 ·
Key symptom: Hoarseness (scratchy or raspy voice) ·
Severity: Generally mild ·
Origin: Omicron subvariant; hybrid of LF.7 and LP.8.1.2

Six key characteristics of the Stratus variant set it apart from earlier strains:

What are the symptoms of the new variant of COVID-19 stratus?

Key symptom: hoarseness

The Telegraph has reported that Stratus may be more likely than earlier variants to cause a hoarse, scratchy, or raspy voice (The Telegraph). This unusual hallmark has become a leading indicator for many clinicians and patients.

Common Omicron-like symptoms

• Congestion and runny nose
• Cough
• Fever or chills
• Headache
• Sore throat
• Muscle aches
• Fatigue

These are consistent with what Ohio State Health describes as typical XFG symptoms — no new or unusual symptoms have emerged beyond the well-known Omicron profile (Ohio State Health experts).

When to seek medical attention

If you experience difficulty breathing, persistent chest pain, confusion, or bluish lips or face, seek emergency care regardless of variant. The NHS advises that most people with mild symptoms can recover at home.

Is this new strain of COVID worse?

Severity compared to earlier variants

Current evidence does not show that Stratus causes more severe disease than previous Omicron subvariants. Ohio State Health states there is “no current evidence that XFG leads to more severe disease or deaths” (Ohio State Health experts). The WHO’s Technical Advisory Group on Virus Evolution assessed that NB.1.8.1 (a related sub-lineage) does not pose additional public health risks relative to other circulating Omicron lineages (Gavi).

Hospitalization rates

UKHSA surveillance indicates that while case numbers are rising, hospitalization rates have not spiked disproportionately (UK Health Security Agency). The variant’s relative growth advantage is estimated at about 31% according to The Telegraph, but this reflects transmissibility, not severity (The Telegraph).

Risk groups

The elderly and immunocompromised remain at elevated risk for any COVID infection. Standard precautions — vaccination, masking in crowded indoors, and early testing — are advised for these groups.

How long does this new COVID last?

Typical duration of symptoms

Most people recover within 5–7 days, consistent with the typical Omicron recovery timeline. Ohio State Health notes that symptoms of XFG are “similar to previous strains,” which generally resolve in under a week (Ohio State Health experts).

Factors influencing recovery time

• Vaccination status: Vaccinated individuals often experience shorter illness.
• Age and health: Older adults and those with underlying conditions may take longer.
• Severity of initial symptoms: Mild cases tend to resolve faster.

When to test negative again

Rapid antigen tests may remain positive for up to 10 days, but most people stop being infectious after 5–7 days if symptoms are improving. The CDC guidance for returning to normal activities remains: at least 24 hours without fever and overall improvement of symptoms.

How can I tell if I have COVID or a cold?

Overlapping symptoms

Both COVID (including Stratus) and the common cold cause sore throat, runny nose, cough, and fatigue. The table below highlights the key differences:

Four symptom categories, one dividing line: loss of taste/smell and hoarseness lean toward COVID.

The implication: a scratchy voice plus any other respiratory symptom is a stronger signal for Stratus than for a cold.

Distinguishing features

Loss of taste or smell is more specific to COVID than colds. For Stratus, hoarseness may be the tell-tale symptom that warrants a test.

Testing as the only reliable method

The NHS and CDC recommend taking a rapid antigen test if you have any respiratory symptoms. Only a test can confirm whether it’s COVID or another virus.

How do I know if I’ve got the new COVID?

Recognizing symptoms of Stratus

If you develop a scratchy or hoarse voice along with other cold-like symptoms, consider the possibility of Stratus. The Telegraph’s reporting highlights that hoarseness is being reported more frequently with XFG than with earlier variants (The Telegraph).

At-home testing options

Rapid antigen tests are widely available and can detect current variants, including XFG. Stony Brook Medicine notes that tests remain effective for identifying infections (Stony Brook Medicine). Most pharmacies and online retailers sell them.

When to consult a healthcare provider

If you test positive and are at high risk (elderly, immunocompromised, pregnant), contact a doctor about potential treatments such as Paxlovid. For otherwise healthy individuals, rest, hydration, and over-the-counter symptom relievers are usually sufficient.

“The most common current variants in the UK remain XFG and NB.1.8.1, sometimes referred to in the media as Stratus and Nimbus.”

— UK Health Security Agency, blog post on September 25, 2025 (UK Health Security Agency)

“There is no current evidence that XFG leads to more severe disease or deaths than previous variants.”

— Ohio State Health experts (Ohio State Health experts)

“WHO assessed the public health risk of NB.1.8.1 as low in May 2025.”

— Gavi, The Vaccine Alliance, citing WHO (Gavi)

For the UK public, the implication is clear: while Stratus is not more dangerous than earlier variants, its mild symptoms make it easy to ignore. Testing when you have a hoarse voice can help curb spread and protect vulnerable neighbors.

Frequently asked questions