NEW YORK: Drugmakers sprinting to deliver potential Covid-19 vaccines say they’re facing a new hurdle: declining infection rates that could make it hard to test their shots.
If the disease ebbs further in some regions, not enough people will be exposed to the coronavirus to make studies possible, AstraZeneca Plc chief executive officer Pascal Soriot said Thursday in a briefing with journalists.
Researchers may have to consider deliberately infecting healthy volunteers with the virus, though it’s still too early to take that step, he said.
“The problem we all have is we are running against time,” Soriot said. “We see already in Europe the disease is declining. It’s still going in the UK, still going in the US. But very soon the disease intensity will be low, and it will become difficult, so we have