Wetin we know about di new Covid variant XXB.1.5?

One new Covid sub-variant don dey cause some concerns for US, wia e dey spread fast.

UK don also dey record some cases.

So wetin you need know about XBB.1.5?

Wetin be XBB.1.5?

Dis na anoda branch of di globally dominant Omicron Covid variant, wey follow di earlier alpha, beta, gamma and delta variants.

Omicron don do pass all previous versions of coronavirus since e start for late 2021, and e don give rise to many sub-variants wey dey even more contagious pass di original.

Experts reason say symptoms of XBB.1.5 dey similar to those of previous Omicron strains, but e still too dey early to confam dis. Most pipo dey experience cold-like symptoms.

XBB.1.5 dey more infectious or dangerous pass earlier variants?

XBB.1.5 evolve from XBB wey begin spread for UK for September 2022, but no dey classified as "variant of concern" by health authorities.

XBB bin get one mutation wey dey help am beat di body immune defences, but dis same quality also reduce im ability to infect human cells.

Prof Wendy Barclay from Imperial College London say XBB.1.5 bin get one mutation wey dey known as F486P, wey dey restore dis ability to bind to cells as e continue to dey evade immunity wey dey make am spread more easily.

She say these evolutionary changes be like "stepping stones", as di virus dey evolve to find new ways of bypassing di body self-defence mechanisms.

Scientists from di World Health Organization (WHO) confam on Wednesday say di XBB.1.5 get "growth advantage" above all oda sub-variants e don see so far.

But dem say no sign dey to show say e dey more serious or harmful pass previous Omicron variants.

Di WHO say e go keep a close watch on lab studies, hospital data and infection rates to find out more about dia impact on patients.

Where XBB.1.5 dey spread?

Over 40% of Covid cases for di United States dey estimated to be caused by XBB.1.5, wey make am di most dorminant strain for di kontri.

For di beginning of December, e bin account for only 4% of cases so e don quickly overtake oda versions of Omicron.

Covid hospital admissions don dey rise in recent weeks across di US.

Di UK Health Security Agency go soon release one report on variants wey dey spread for di UK next week, and fit refer to XBB.1.5.

Scientists dey worry about XBB.1.5?

Prof Barclay say she no dey especially concerned about di general UK population because "no indication" shw say di XBB.1.5 go "breakthrough" di protection against severe illness wey di vaccines dey provide.

But she dey worried about its effect on di vulnerable, wey include di immunocompromised, wey get less benefit from Covid jabs.

Prof Hunter say im no see evidence say XBB.1.5 dey more virulent, wey mean say e  no dey likely to "put you for hospital or kill you" than existing Omicron variants.

He add: "E dey ironic say everyone dey focus on possible variants emerging from China, but XBB.1.5 come out of di US."

Prof David Heymann from di London School of Hygiene and Tropical Medicine acknowledge say things still dey to learn about dis latest variant.

But e say e dey unlikely to cause major problems for kontris like UK wey get high levels of vaccination and previous infections.

Im concern dey for kontris like China, where low take-up of vaccines and little natural immunity dey because of prolonged lockdowns.

"China need to share clinical information on pipo infected in order to see how di variant dey behaves in a non-immune population," Prof Heymann tok.