The vaccination campaign against Covid-19 in India and China will extend into late 2022 because of the massive size of their population while more than 85 poor countries will not have adequate access to vaccines before 2023, according to a study carried out by the Economist.

“Most developing countries will not have widespread access to the shots before 2023 at the earliest,” Agathe Demarais, director of the Economist Intelligence Unit, the research division of the Economist Group, said in its study.

“Some of these countries—particularly poorer ones with a young demographic profile—may well lose the motivation to distribute vaccines, especially if the disease has spread widely or if the associated costs prove too high.”

Most countries in Africa are unlikely to get widespread vaccination coverage until early 2023, while many Asian countries will have broad access to vaccines by late 2022.

The report said vaccine deliveries to poor countries by WHO’s global vaccine sharing scheme COVAX, may be slow due to delays in delivery as wealthy nations are getting the vaccines first and poor infrastructure in the developing world will also prove to be a handicap.

COVAX said 1.8 billion doses would be supplied to 92 poorer countries in 2021 and that would correspond to approximately 27% coverage of populations in those countries.