Why AstraZeneca dey withdraw dia Covid vaccine afta more dan three billion doses

Afta more dan three billion doses, AstraZeneca don withdraw di Oxford-AstraZeneca Covid vaccine.

AstraZeneca tok say dem dey "incredibly proud" of di vaccine, but dem don make commercial decision.

Di organisation tok say di rise of new coronavirus variants mean say demand don shift go di newer updated vaccines.

Many pipo reason say dia vaccine bin save millions of lives during di pandemic, but e also cause rare, and sometimes deadly, blood clots.

For di race to comot di world out of pandemic lockdowns, scientists for di University of Oxford bin develop di Covid vaccine in record time. Di process wey normally dey take 10 years, dem speed am down to about 10 months.

For November 2020, dem parade am as "vaccine for di world" as e dey far cheaper and easier to store pass oda Covid vaccines. Di pharmaceutical giant AstraZeneca bin agree to manufacture plenty.

Initially, UK plan na to vaccinate everybody as way out of lockdown.

"Di truth na say e make big difference, na wetin comot us from di disaster wey bin happun dat time, plus di oda vaccine from Pfizer," Prof Adam Finn, from di University of Bristol tok.

However, dia reputation shake as unusual blood clots begin show as rare side effect of di vaccine, and UK turn to alternatives.

For one statement, AstraZeneca say: "According to independent estimates, ova 6.5 million lives dey saved for di first year of use alone.

"Governments around di world recognise our efforts and dem regard am as critical component of ending di global pandemic."

Dem tok say di development of new vaccines wey closely match di mutated forms of Covid wey dey circulate now mean say "surplus of available updated vaccines dey", and e don lead to "decline in demand" for dia own vaccine wey dem "no longer dey manufacture or supply".

Prof Finn add: "I think di withdrawal of di vaccine mean say e no dey useful again.”

"E show say dis virus dey very alert and e dey change, so di original vaccines no dey work for dem again, so di old vaccine don become irrelevant and na only di reformulated vaccines dey in use now.”