Anti-vaxxers use Seychelles to take jab at vaccines. Do they have a case?
Covid surge in most immunised nation has thrown a spanner in the works for scientists. What’s really going on?
For epidemiologists, the past year and a half has been a voyage of discovery. Recently their journey aboard Sars-CoV-2 took an unexpected turn toward Seychelles, a palm-fringed archipelago in the Indian Ocean with fewer than 100,000 inhabitants. A country that few could pinpoint on a map suddenly became internet-famous as the most vaccinated nation on Earth, with 64% of the population having received the requisite two shots. Yet to the surprise of virologists — and the dismay of the government, which had been counting on the immunisation drive to reopen the tourism-dependent economy — the infection count has been ticking up. As of May 13 a third of active cases — about 900 in all — were among residents who’d been fully vaccinated.
Vaccine sceptics pronounced themselves vindicated, while international health experts have been scrambling to answer a host of questions without the benefit of robust data. Did one or both of the vaccines used in Seychelles fail? Has herd immunity not been reached? Is the nation grappling with a more infectious variant capable of evading the defences that certain types of vaccines provide?
“So what’s going on?” asked Raina MacIntyre, professor of global biosecurity at the Sydney campus of the University of New South Wales, during an online presentation on May 18. “It’s probably that the herd immunity threshold hasn’t been reached, plus or minus, if it’s the SA variant in there.”..