At the beginning of the pandemic, Covax struggled with vaccine availability as richer countries were seen rushing to nail down the first available doses. Now that that output is adequate to vaccinate all populations, thousands of doses are threatening to expire because they don’t reach the intended recipients promptly, the news agency said.

In Africa, where only 10% of the population has been vaccinated against Covid-19, compared with 70% globally, state authorities and Covax reportedly are rejecting shipments of doses, as many arrive only a few months, or just weeks, away from the recommended “use-by” date. In December last year, Reuters reported that Nigeria had dumped up to 1 million AstraZeneca doses. 

Covax lays a major part of the blame at AstraZeneca’s door. According to the WHO document, most of the 19 African nations supplied by the distribution program were sitting on expired doses from the Cambridge, UK-based drugmaker, compared with “a handful” of doses from other manufacturers.

The WHO calculates that many more vaccines will likely be rejected in future, as African nations and Covax plan to stop accepting supplies of doses with less than two-and-a-half months' shelf life, the minimum duration they believe is needed to safely administer the shots.

Covax and AstraZeneca have relativized the problems somewhat, and even WHO Africa told the news agency that, "since January 2022, Covax has been shipping vaccines to countries on demand, ensuring they get the right volume at the right time.” WHO‘s African arm said, however, that it is “fully cognizant of the pressure that short-shelf-life doses put on delivery strategies and systems amid weak infrastructure and low demand."

AstraZeneca, the second-largest supplier to Covax behind Pfizer/BioNTech, acknowledges that since the start of the global rollout, more than 250 million of its shots have been prepared for distribution with less than two-and-a-half months before expiry, but says this was mainly because they had to undergo scrupulous quality checks.

Altogether, more Covid-19 vaccines distributed by Covax were made by the AstraZeneca than any other company. It has donated 2.6 billion doses globally, about two-thirds to low and lower middle-income countries. But the company told Reuters that, almost nine out of 10 doses released from its manufacturing sites have a shelf-life of at least two and a half months which it said is “consistent with the rest of our supply chains."

Some of those commenting on the problem said that, alongside the short shelf-life of the AstraZeneca doses, Covax’s distribution system that assigns doses to countries and handles donors' requests to deliver them may be too complex, as it further eats into the vaccine's short life.

According to storage instructions approved by the WHO, the J&J vaccines can last two years when frozen, while Pfizer/BionTech’s have a shelf life of nine months and Moderna's seven months.  However, African countries told the WHO that other Covid vaccines are threatened with expiry, due to low uptake and insufficient cold-chain equipment to distribute them to remote regions.

Gavi told Reuters it has encouraged AstraZeneca to apply to the WHO for an extension of the expiration date, but the talks have not led yet to a formal application. The drugmaker points to its wide network of companies manufacturing its shots as one of the major issues.

WHO has already granted approval to the Serum Institute of India for an extended shelf life of nine months, after it was initially authorized only for six, Reuters was told. All the batches produced by AstraZeneca’s other partners have a shelf life of only six months.

Author: Dede Williams, Freelance Journalist