Pfizer and BioNTech will provide an additional 500 million doses of their Covid-19 vaccine to the U.S. government to be donated to low and lower-middle-income countries.

This move, which is an extension of the existing agreements between the two companies to supply additional vaccine doses at no-profit prices to less-advantaged countries, was announced Wednesday. It brings to one billion the number of doses that will be donated to these countries.

In line with the initial agreement, the U.S. government will allocate doses of the Pfizer-BioNTech Covid vaccine to 92 low and lower-middle-income countries and the 55 member states of the African Union, Pfizer said in a press statement Wednesday.

The initial 500,000,000 doses were delivered in August. Pfizer stated that the remaining 1 billion doses of the expanded agreement will be available by September 2022.

Mid-August saw the arrival of the first doses through this program in Rwanda. More than 30,000,000 doses have since been sent to 22 countries.

Pfizer, BioNTech and the Coalition for Epidemic Preparedness Innovations have an agreement to supply vaccine doses for the COVAX Facility. This facility was established by Gavi and the Vaccine Alliance. It aims to give poorer countries early access to Covid-19 vaccinations.

In the meantime, many vaccine candidates that were created at lightning speed have been approved to be used in emergency situations last year. Then they were rolled out in mass vaccination campaigns and distributed in developed countries such as the U.S.

Although the majority of adult Americans and Europeans are fully vaccinated now, there is still a large number of unvaccinated people in other parts of the globe. This greatly decreases the chance of serious Covid infections, hospitalizations, and even death.

In the U.S., 64.1% of the population above 12 years of age is fully vaccinated, according to CDC data, while in the U.K., 81.9% of people over 16 are fully vaccinated, British government data shows. In the EU, 71.7% of adults are fully vaccinated, according to the European Centre for Disease Prevention and Control.

Our World in Data figures note that while 43.5% of the world population has received at least one dose of a Covid vaccine, only 2% of people in low-income countries have received at least one dose.