H5N1, the avian flu virus, may have reached a milestone in its pilgrim to land on human. In Turkey, a cluster of 21 people were infected by the virus, and 4 of them died. In the two Turkish samples, WHO found three mutations in the virus.

According to the Nature news, the first mutation involves a substitution of an amino acid at position 223 of the haemoagglutinin receptor protein, the protein binding to human cells. The second mutation is at position 153 of the haemoagglutinin protein but its function is unknown. The third mutation is at position 627 of the polymerase protein, the gene replicating protein, which results a substitution of glutamic acid with lycine.

However, these are not trivial mutations. The 223 mutation in H protein signals adaptation to humans, while the 627 mutation in polymerase protein also occurs in the 1918 flu. The danger of pandemic flu is closer than before.

Also unnoticed by the public, another human infection case was reported in China, which coincided with the international bird flu meeting in Beijing. Worldwide, there are 149 human cases reported to WHO. Among them, 80 died.

Current bird flu pandemic in birds actually has been lingering around since mid 2003. Human cases were reported in Viet Nam as early as in late 2003. Retrospectively, it surprises me that we are not in a bird flu pandemic yet.

Think about this, the virus replicates very fast but erroneously, the number of viruses is at the scale of billions and billions, and it has gone through millions of generations. Even if the probability of having a human friendly mutation is one over ten billions, that kind of mutation has surely occurred. It just didn’t find a chance to jump to humans, or it wasn’t smart enough to survive on humans. How lucky we are!

Indeed, people dwell on this illusion of safety contently. After several months of panic bed tossing, people gradually forget about the bird flu. We enjoy the holiday season, debate Iraq, and talk about gay and geisha. After all, bird flu is in Asia. Let health workers and WHO deal with it.

It is probably true that common people and news media are of little use in preparing for the pandemic. They incur more chaos and fuss than orders and helps. On the other hand, it is this kind of negligent behavior that may facilitate spreading the virus. All the preparation may be comprised and ineffective if people are tired of warnings.

Humans are getting lazy, but the bird flu virus is still working hard and ingeniously. Let’s cross our fingers, give the virus a little more time, and hope it will go away by itself.