Mon 16 Mar 2020 / Laura Spinney
Even at their most effective – and draconian – containment strategies have only slowed the spread of the respiratory disease Covid-19. With the World Health Organization finally declaring a pandemic, all eyes have turned to the prospect of a vaccine, because only a vaccine can prevent people from getting sick.
About 35 companies and academic institutions are racing to create such a vaccine, at least four of which already have candidates they have been testing in animals. The first of these – produced by Boston-based biotech firm Moderna – will enter human trials in April. 
This unprecedented speed is thanks in large part to early Chinese efforts to sequence the genetic material of Sars-CoV-2, the virus that causes Covid-19. China shared that sequence in early January, allowing research groups around the world to grow the live virus and study how it invades human cells and makes people sick.
But there is another reason for the head start. Though nobody could have predicted that the next infectious disease to threaten the globe would be caused by a coronavirus – flu is generally considered to pose the greatest pandemic risk – vaccinologists had hedged their bets by working on “prototype” pathogens. “The speed with which we have [produced these candidates] builds very much on the investment in understanding how to develop vaccines for other coronaviruses,” says Richard Hatchett, CEO of the Oslo-based nonprofit the Coalition for Epidemic Preparedness Innovations (Cepi), which is leading efforts to finance and coordinate Covid-19 vaccine development.