Time to Worry?
The recent cluster of human bird-flu deaths in Indonesia sure got media attention. Now that the World Health Organization (WHO) no longer denies[1] human-to-human transmission of the highly pathogenic H5N1 virus, what is there to do? Panic? To keep tuning out bird flu hype? Or what?
Human-to-human transmission of H5N1 is not new. A recent publication lists 15 familial clusters by July 2005 (see table from Olsen et al. 2005, below).[2] What does appear to be new is that so many members of one family -- 7 out of 8 -- got ill and died. The delays between groups of family members falling ill suggest three to four successive links in the chain of human-to-human transmission. Also unusual is that no source of the infection has been found, at least so far, which leaves open the possibility of a human carrier as the source.
Mutation?
Does all of this mean that the virus has mutated and become more easily transmitted from person to person? We don’t know. The WHO statement says that analyses of the virus’s genetic material showed “no evidence of significant mutations.” Since WHO withholds that sequence information from the public, their statement is impossible to verify, and it remains unclear what “significant” means.
What Else, If Not Mutation?
“… three of the confirmed cases spent the night of 29 April in a small room together with the initial case at a time when she was symptomatic and coughing frequently.”
Virus-laden particles can infect cells deep down in the human respiratory tract.[3] But to get there, droplets must be within the right size range. It is quite likely that such droplets released from coughs may have transmitted the virus. Neither a common environmental exposure, nor any new mutation would be necessary to explain the clustered cases. At this point, the likelihood seems small that this cluster of cases would be the start of a pandemic -- unless it should turn out that the chain of transmission keeps on going.
There is a remote possibility that the mutations made the virus more infectious for humans, even though WHO deems them not “significant.” Without full genetic sequence information we can’t be sure. In spite of international criticism, WHO still keeps vitally important data locked up in a database accessible only to a few privileged participants.[4]
Is There Reason to Worry?
I think there is reason to worry, not so much because of this latest cluster of H5N1 infections, but because of what would happen if sometime within the next 5 or so years the virus became efficient in moving from human to human. I worry because the governments and institutions we organize and pay to protect us failed to do so. There is no effective set of countermeasures. You don’t have to take my word for it:
“… politicians and policy-makers have become over-confident about how they might defeat a highly transmissible and pathogenic virus. Experts in Singapore agreed that there are few truly effective and, most importantly, no coordinated global, regional, or national preparedness plans.”
(The Lancet 2006)[5]
I take this to mean that you, I, and our families are on our own, and will be for some time, even with billions of dollars appropriated for vaccine development and other flu-fighting efforts.
What Is Going to Happen?
First, we have to accept that nobody knows when the next influenza pandemic will occur and how bad it is going to be. There are many strong but wrong statements in the face of this uncertainty. The various circulating virus strains will evolve in microscopic steps under circumstances that at present are poorly understood, cannot be predicted with any accuracy, and cannot be controlled.
It is possible that there will be a few more outbreaks of bird flu and nothing much will happen after that. It is also possible that bird flu will become as infectious as “normal” human flu and remain as deadly as it is now. The more likely outlook is somewhere in between.
What Can You Do?
My take is that it’s neither time to panic, nor to be complacent, but to prepare for the worst and hope for the best -- trite, but probably as useful as any other advice. Here is a starter kit:
- Inform yourself.
If you want to keep track of the torrent of bird flu news from all over the globe, you might want to check in with “Bird Flu Breaking News,” which is updated every 10 minutes: http://www.birdflubreakingnews.com/
If you prefer a source that condenses the news and applies some informed judgment, check out the Center for Infectious Disease Research & Policy, University of Minnesota (CIDRAP): http://www.cidrap.umn.edu/index.html
- Prepare to prepare.
Even if you don’t feel like making preparations now, you may find it useful to know where to turn, should the time come, when it is obvious to you that you need to get going.
A ready-made guide is Grattan Woodson’s Preparing for the Coming Influenza Pandemic. Woodson is a physician who wrote the booklet for his patients. You can buy it in hardcopy[6] or download the most recent edition.[7]
- Make preparations.
Given the uncertainty of how the bird flu is evolving, there is no right or wrong level of preparation. But I think it would be foolish to not be informed. Follow your own informed judgment, and do a little more than seems to be needed right now -- just in case.