HAVANA (Reuters)

Cuba, grappling with a dire COVID-19 outbreak fueled by the Delta variant, said “only 21,000,” or 0.8 per cent of the 2.5 million people inoculated with its homegrown vaccines, had fallen ill with the disease so far.

Of those, 99 or 0.003 per cent of those inoculated had died, in what state biopharmaceutical corporation BioCubaFarma said late on Thursday (August 12) was an encouraging sign that the shots were working, including against Delta, in particular, to prevent severe illness.

“This is really promising data,” BioCubaFarma head Eduardo Martinez said on state-run television. The corporation is on track to produce the doses necessary to fully inoculate the whole population with its three-shot vaccines, Abdala and Soberana 2, by September, he added.

Skeptics of the Cuban vaccines pointed out the data still yielded a case-fatality rate of 0.47 per cent. Cuba had previously said that the rate in the first week of August was 0.93 per cent for the whole country regardless of vaccination status.

Any reliable comparison is tricky, with recent reports from provincial state news outlets suggesting underreporting of both cases and deaths in official statistics amid Cuba’s worst outbreak since the start of the pandemic.

The island state of 11 million inhabitants is racing to fully inoculate its population as it battles one of the world’s highest COVID-19 caseloads, with more than 8,000 confirmed cases per day for the last two weeks.

Authorities started a mass vaccination campaign in Havana in May with Abdala and Soberana 2 which they say have proven to be more than 90 per cent effective in late phase clinical trials, although the data has yet to be published in peer-reviewed journals.

Communist-run Cuba has developed an unusually large biotech sector for a country its size, partly in a bid for sovereignty given crippling U.S. sanctions.

It is the only Latin American country to have advanced with a COVID-19 vaccine to late phase trials, and Abdala and Soberana 2 have elicited interest from countries worldwide.