Wednesday, October 05, 2005

Protection from avian bird flu - lessons from computer viruses

How does a country protect itself from the avian bird flu?

One method of rapid widespread bird flu infection once human infection begins will be from infected travelers carrying the virus into new destinations.

An important initial step to gain time for vaccine production will be to block the spread of infection at points of entry for travelers.

Using the computer security firewall approach of starting with a 'deny all' policy to all traffic with specific rules to allow access for known safe traffic

At airports this will be a reversal of the 'allow all' and block the identified bad people approach in place today which uses flawed thinking that all known threats are the only threats. The problem with this approach is that it creates a window of opportunity for new threats to become realized, before they become known and countermeasures can be put in place.

An example is a new vulnerability affecting web servers for which no current 'badness' signature is available. Under the 'allow all' rule this new threat will bypass security as it is not in the know list of bad traffic to be blocked.

All agreed acceptable people (traffic) are permitted entry i.e. those from known locations with no cases of human bird flu in and the traveler has resided there for more than the incubation period, all others are blocked for further investigation or testing.