COVID vaccination programmes are rolling out across Europe and the rest of the world but differences are already emerging in terms of speed and availability.
The World Health Organisation has cautioned against a vaccination race, saying it favours wealthy nations.
"At present, 42 countries are rolling out safe and effective COVID-19 vaccines," WHO Director-General Tedros Adhanom Ghebreyesus said.
"Thirty-six of these are high-income countries and six are middle-income countries, so there is a clear problem that low and most middle-income countries are not receiving the vaccine yet... vaccine nationalism hurts us all and is self-defeating."
The People's Vaccine Alliance estimates that, at present, developing countries will only be able to vaccinate one in 10 people.
Rich nations, including the EU bloc, have bought enough doses to protect their entire populations three times over if all the vaccines ordered are approved for use.
Because it doesn't need to be transported and stored at ultra-low temperatures, the Oxford-AstraZeneca vaccine may be the key for many low-income countries.
It's already being administered in the UK, but the provider is also pledging to deliver two-thirds of its doses to people in developing nations.