Experts have warned that unless most of the global population is vaccinated, the world faces a far longer bout with the coronavirus than anticipated. Vaccine inequality remains the greatest challenge. The COVAX scheme which was designed to ensure equal access to vaccines worldwide is yet to achieve its vision. It's failure to coax a large number of wealthy countries to join the programme has left it in an awkward situation. #Vaccine nationalism has been a trend in wealthier countries, leaving those in poorer countries in dire conditions. Sara Firth has this report.