Monday, January 16, 2006

Marking time in Turkey

The big question about any bird flu outbreak is whether it is spreading person to person. If a mutation has occurred that makes it easer to pass from birds to humans, it stands to reason that it is also easier to pass from human to human, unless for some reason there is less viral shedding (which is possible). There have been some well documented instances of family clusters where the timing strongly suggests human to human transmission. So it is reasonable WHO would be concerned.
Health authorities are studying whether the latest fatal outbreak of bird flu in Turkey has been spread by human-tohuman contact for the first time.

The World Health Organisation is examining a mother and her child who were infected with the virus to determine whether a mutation of the H5N1 strain has occurred which could trigger a global pandemic.

The 78 people who have died from bird flu to date are thought to have caught the disease from direct contact with infected poultry. However, Guenael Rodier, the WHO's head of communicable diseases and response, said yesterday questions had been raised by the latest outbreak.

He said: "When you have a mother and a child, and both get sick, you don't know if they both were exposed to the chickens, or if the mother got sick because she was caring for the child. It leaves room for some question marks. We have not documented every transmission story." (via tmcnet)
And if it was spreading person to person? A lot depends on how readily that is happening and how often. But further statements of Mr. Rodier, that the virus could spread like SARS and still be contained, seem forced since the two diseases have very different epidemiologies. SARS is primarily transmissible after the patient has become obviously ill, which is both why health care workers were the main victims and isolation may have had some effectiveness. People infected with influenza virus, on the other hand, are contagious before they develop symptoms. Isolation won't stop this disease.

If it is now person to person, we can hope it is not yet very transmissible in that fashion. Then it might stay an indolent, smoldering infection in the population for a period long enough for us to get better prepared before it finds the right recipe for reproducing itself via easier and quicker transmission. Indeed, that may be the position we are in now. Then again, maybe not.

We are marking time while we figure out what is going on. Meanwhile Turkey has registered a fourth death and a 19th confirmed case. This outbreak is not over.

And in Indonesia we have a 13 year old girl and two of her siblings testing positive for H5N1 (Jakarta Post). This is at least the fifth family cluster there, with 20 cases overall and 13 deaths. A man in Isreal who owned chickens that became ill has been admitted to a hospital thereto rule out bird flu (Bloomberg), and in China there have been four deaths since November.

As we have noted many times here, this virus is now geographically dispersed and entrenched in a vast poultry population, much of it in close contact with humans. Its only objective is to reproduce and by genetic variation seeks a good recipe for doing so. Since there are trillions of such natural experiments going on at any one time, it seems almost inescapable that if such a recipe exists the virus will happen upon it sooner or later. Preparing for it has two huge benefits. It will mitigate the effects of a pandemic should one occur, and it will strengthen our public health and social service infrastructures in a generic way that will repay us many fold for other challenges.

A much better investment than a Bridge to Nowhere, Senator Stevens (R-Alaska).