On his VDU's blog, Dr. Ian Mackay is really unhappy: Why have a case definition that seems designed to miss transmission events? Excerpt (but read the whole post and follow the links):
FluTrackers just tweeted a link to a story they have posted from Korea which I've excerpted below.
I don't usually excerpt, so take it as a measure of my complete dismay about this.
Asymptomatic Carriers of AI Confirmed in S. Korea 2014-02-04
...The Korea Centers for Disease Control and Prevention confirmed that ten people who had participated in culling birds during the outbreaks of bird flu in 2003 and 2006 had antibodies for the H5N1 strain of avian influenza....
...The agency said that it had announced before that there were no human infection cases as asymptomatic carriers are not regarded as patients under the World Health Organization standards.
What? Seriously? You cannot be listed as a Case unless you are symptomatic?!
I can understand that a symptomatic Case will require medical care and resources and is a priority in counting the true human toll from an infectious agent spreading among people, but to be excluded from any Case counts when you are still a viable piece in the transmission chain puzzle (see image below)? That makes no sense to me at all. Unless there is concern that the laboratory is at fault or that the test is untrustworthy. But there are no mentions of those issues.
Mike Coston at Avian Flu Diary is also on this story, which certainly poses problems for the Koreans. An asymptomatic case is still a case, and carrying antibodies indicates you've had a disease whether or not you showed symptoms at the time.