(((((((BIG..NEWS)))))))US.INVOKES.EMERGENCY.ACT.TO.KEEP.H7N9.​FLU.AT.BAY

THE US government has declared that H7N9 bird flu "poses a significant potential for a public health emergency", and has given "emergency use authorisation" for diagnostic kits for the virus. This means tests can be used that haven't gone through the usual lengthy approval process by the US Food and Drug Administration.

They are right to be concerned. H7N9 could be a tough adversary: New Scientist has learned that it provokes a weaker immune response than most flu, making vaccines hard to produce.

Although H7N9 is not, so far, transmissible between humans, it does cause severe disease in people, is easier to catch than other bird flu strains, and may need only a few mutations to go pandemic. The UK has already given doctors instructions on when to test people for H7N9, and how to manage any with the virus.

The US's emergency authorisation will allow the use of a kit that looks for flu genes using a polymerase chain reaction test, which has been made specific for H7N9. The kit has had preliminary tests but would normally need more exhaustive tests to be approved. Innovative new diagnostics should eventually be authorised too, says Charles Chiu of the University of California in San Francisco.

This kind of fast, high-throughput screening for pandemic flu, possibly at borders, might allow early cases to be treated with antiviral drugs, potentially slowing the spread of the virus while vaccines are made.

The next emergency authorisation is likely to be for immune-stimulating chemicals called adjuvants to put in those vaccines. These were used in vaccines in Europe and Canada during the 2009 pandemic, but adjuvants suitable for flu are not currently approved in the US.

More at link... [link to www.newscientist.com]