SOURCE: AFP and AL JAZEERA

■ British health au­thor­i­ties have iden­ti­fied hun­dreds of cas­es of the Omi­cron vari­ant dubbed BA.2 ■

(AL JAZEERA) — Sci­en­tists are keep­ing a close watch on a re­cent­ly-dis­cov­ered sub-vari­ant of the Omi­cron vari­ant of the coro­n­avirus to de­ter­mine how its emer­gence could af­fect fu­ture pan­dem­ic spread.

The ini­tial Omi­cron vari­ant has be­come the dom­i­nant virus strain in re­cent months but British health au­thor­i­ties have no­tably iden­ti­fied hun­dreds of cas­es of the lat­est ver­sion, dubbed BA.2, while in­ter­na­tion­al da­ta sug­gest it could spread rel­a­tive­ly quick­ly.

The UK Health Se­cu­ri­ty Agency (UKHSA) iden­ti­fied more than 400 cas­es in Britain in the first 10 days of this month and has in­di­cat­ed the lat­est vari­ant has been de­tect­ed in some 40 oth­er coun­tries, ac­count­ing for a ma­jor­i­ty of most re­cent cas­es in some na­tions in­clud­ing In­dia, Den­mark and Swe­den.

The UKHSA in­di­cat­ed on Fri­day it had des­ig­nat­ed the BA.2 sub-lin­eage as a vari­ant un­der in­ves­ti­ga­tion (VUI) as cas­es of it were on the in­crease even if, in Britain, the BA.1 lin­eage cur­rent­ly re­mains dom­i­nant.

The au­thor­i­ty un­der­lined that “there is still un­cer­tain­ty around the sig­nif­i­cance of the changes to the vi­ral genome”, which re­quired sur­veil­lance as, in par­al­lel, cas­es in re­cent days showed a sharp rise in BA.2 in­ci­dence no­tably in In­dia and Den­mark.

“What sur­prised us is the ra­pid­i­ty with which this sub-vari­ant, which has been cir­cu­lat­ing to a great ex­tent in Asia, has tak­en hold in Den­mark,” French epi­demi­ol­o­gist An­toine Fla­hault told the AFP news agency.

Sci­en­tists must eval­u­ate how the virus con­tin­ues to evolve and mu­tate. Its lat­est in­car­na­tion does not pos­sess the spe­cif­ic mu­ta­tion used to track and com­pare BA.1 with Delta, the pre­vi­ous­ly dom­i­nant strain.

BA.2 has yet to be des­ig­nat­ed a vari­ant of con­cern – but Fla­hault says coun­tries have to be alert to the lat­est de­vel­op­ment as sci­en­tists ramp up sur­veil­lance.

“[France] ex­pect­ed a spike in con­t­a­m­i­na­tions in mid-Jan­u­ary. It didn’t hap­pen and per­haps that is due to this sub-vari­ant, which seems very trans­mis­si­ble but not more vir­u­lent” than BA.1, he ob­served.

“What in­ter­ests us is if this [sub-vari­ant] pos­sess­es dif­fer­ent char­ac­ter­is­tics” from BA.1 in terms of con­ta­gious­ness and sever­i­ty, France’s pub­lic health agency said on Fri­day.

To date, on­ly a hand­ful of BA.2 cas­es have emerged in France – but the coun­try is mon­i­tor­ing de­vel­op­ments as they spread across the Chan­nel.

‘Com­pa­ra­ble sever­i­ty’

Fla­hault, di­rec­tor of the Uni­ver­si­ty of Gene­va’s In­sti­tute of Glob­al Health, says the watch­word is not pan­ic but “vig­i­lance” as “for now we have the im­pres­sion [BA.2 case] sever­i­ty is com­pa­ra­ble to” clas­sic vari­ant Omi­cron cas­es.

“But there are nu­mer­ous ques­tions on the ta­ble” and a need to mon­i­tor prop­er­ties of the new vari­ant on the block.

“Very ear­ly ob­ser­va­tions from In­dia and Den­mark sug­gest there is no dra­mat­ic dif­fer­ence in sever­i­ty com­pared to BA.1,” tweet­ed Tom Pea­cock, a vi­rol­o­gist at Im­pe­r­i­al Col­lege, Lon­don, adding the lat­est vari­ant should not call in­to ques­tion the ef­fec­tive­ness of ex­ist­ing vac­cines.

Pea­cock stressed, “We do not cur­rent­ly have a strong han­dle on … how much more trans­mis­si­bil­i­ty BA.2 might have over BA.1. How­ev­er, we can make some guess­es/ear­ly ob­ser­va­tions.”

“There is like­ly to be min­i­mal dif­fer­ences in vac­cine ef­fec­tive­ness against BA.1 and BA.2. Per­son­al­ly, I’m not sure BA.2 is go­ing to have a sub­stan­tial im­pact on the cur­rent Omi­cron wave of the pan­dem­ic,” he added.

“Sev­er­al coun­tries are near, or even past the peak of BA.1 waves. I would be very sur­prised if BA.2 caused a sec­ond wave at this point. Even with slight­ly high­er trans­mis­si­bil­i­ty this ab­solute­ly is not a Delta-Omi­cron change and in­stead is like­ly to be slow­er and more sub­tle,” he fore­cast.

French Health Min­is­ter Olivi­er Ve­r­an said on Thurs­day that BA.2 did not look as if it would prove a game-chang­er as vari­ants ap­pear on the scene “fair­ly reg­u­lar­ly”. But he in­di­cat­ed he would re­serve judge­ment.

“What we know for now is that [BA.2] more or less cor­re­sponds to the char­ac­ter­is­tics that we know of Omi­cron” mark one.