China recently revealed that its COVID-19 vaccines aren't all that effective, and that's bad news for Chile, which is using the Chinese Sinovac vaccine. Public health experts say people started getting lax about public health precautions too quickly after just the first dose of the two-dose vaccine started being given, the Wall Street Journal reports. "With one dose, we know the protection is very weak," says one Santiago infectious disease expert. "It was not clearly explained that you need two doses—that you need to wait." COVID is currently surging in Chile, despite the country rolling out vaccinations faster than any other Latin American nation—indeed, its vaccination rate is one of the best in the world, CNBC reports. Experts are warning other countries starting to use Sinovac not to make the same mistake.
A new Chilean study finds Sinovac is just 16% effective after one dose, and 67% effective after two. A previous study found it was just 3% effective after the first dose, and 56.5% after the second. But officials in the country are defending the vaccine, and say that its use is the reason the current surge is less deadly; the second study found the vaccine to be 80% protective against death. Severe cases and deaths amongst the elderly, in particular, have been dropping, though the country saw its highest-ever number of new infections in a single day this month. Half of the country's adult population has received at least one dose. Even so, critics say the government should not have started easing restrictions so quickly; after theater restarted, for example, one play saw almost all of its actors infected with the coronavirus, two of them fatally. (Read more Sinovac stories.)