UK Covid cases rise linked to Stratus and Nimbus Omicron subvariants

Health officials and clinicians in the United Kingdom are reporting a rise in Covid-19 cases driven by two Omicron subvariants, commonly referred to as Stratus and Nimbus, with clinicians warning of a distinctive sore throat and hoarseness among some patients. The Royal College of General Practitioners said cases have doubled over the past four weeks, and recent sequencing by the UK Health Security Agency identified multiple samples of XFG lineage viruses, associated with Stratus, and NB.1.8.1, associated with Nimbus.

Clinicians and public health bodies say many infections with these variants present with symptoms that overlap with seasonal colds and influenza, complicating diagnosis without testing. Several doctors have highlighted a pronounced sore throat and a hoarse or “razor blade” type throat pain as a more common feature in the current wave, alongside familiar Covid symptoms such as headache, cough, runny or blocked nose, fatigue and, in some cases, gastrointestinal complaints.

Dr Sara Kayat, a clinician who has addressed the public about the variants, said cases are increasing and described the key signs to watch for as “mainly a hoarse voice and a kind of razor blade...