COVID-19 vaccine boosters may have 'huge' impacts on global supply

If wealthy nations — currently flush with COVID-19 vaccines — decide to give their populations booster shots, it could have “huge implications” for the availability of doses globally, a World Health Organization official said during a press conference Thursday.

The statement by Africa Regional Director Matshidiso Moeti came a day after Pfizer said a third dose of its vaccine could improve immunity. While receiving two doses still provides strong, sustained protection against serious disease, effectiveness decreases over six months. The company said it plans to seek U.S. approval for a booster shot.

Why this matters: Many wealthy countries have hoarded large supplies of vaccine doses, including by reserving them through prepayments with manufacturers. This has limited availability for low-income countries that, even with access to financing, have struggled to purchase doses.

Fewer than 2% of the people on the African continent are fully vaccinated.

Now that wealthy countries have vaccinated large portions of their populations, they are starting to donate doses. U.S. President Joe Biden announced last month that his government would give 500 million Pfizer doses to low- and lower-middle-income countries.

But booster shots could change this, according to Moeti.

“Our concern is [that] decisions to provide a third dose might influence the availability of vaccines for our countries, which are already going through a very difficult situation,” she said.

More doses needed: The African Union, which aims to vaccinate 60% of the continent’s population, also anticipates needing more doses than initially projected, as the delta variant has increased the coronavirus’s rate of reproduction.

“We may need more vaccines than we initially stated,” said John Nkengasong, director at the Africa Centres for Disease Control and Prevention.