<prompt> tafadhali geuza maudhui haya ya swahili kwenda kwa kiingereza.mpango wa chanjo duniani unaofahamika kama covax, inakusudia kusaidia kununua na kusambaza kwa usawa dozi bilioni mbili za chanjo zilizoidhinishwa ifikapo mwisho wa mwaka 2021.  <response>: the global vaccine initiative, known as covax, aims to help buy and fairly distribute 2 billion doses of vaccines approved by the end of2021. 