Protecting the world from deadly H7N9 flu

摘要

Suited and masked, in the secure environment of a biosafety level 3 containment lab at St Jude Children's Hospital in Memphis, Tennessee, Jim Allay and Mike Tillman are lifting culture plates above their heads, peering towards the fluorescent lighting. They're looking for robust "plaques" - clumps of chicken embryo kidney cells infected with an engineered flu virus. The stakes could scarcely be higher. This virus is a vaccine strain carrying genes from the H7N9 bird flu that has killed more than 30 people in China. If H7N9 acquires the mutations it needs to pass from person to person, the "seed strain" that the St Jude team is racing to produce could be the main line of defence against a flu pandemic that would threaten millions of people.