"Passage" through humans can lead to higher virulence in new flu strains.

[Ladyhawk]

I've tried posting this in my own words. I'll let author John M. Barry do the talking:

What’s important to keep in mind in assessing the threat of the current outbreak is that all four of the well-known pandemics seem to have come in waves. The 1918 virus surfaced by March and set in motion a spring and summer wave that hit some communities and skipped others. This first wave was extremely mild, more so even than ordinary influenza: of the 10,313 sailors in the British Grand Fleet who became ill, for example, only four died. But autumn brought a second, more lethal wave, which was followed by a less severe third wave in early 1919.

The first wave in 1918 was relatively mild, many experts speculate, because the virus had not fully adapted to humans. And as it did adapt, it also became more lethal. However, there is very good evidence that people who were exposed during the first wave developed immunity — much as people get protection from a modern vaccine.

-snip-

In all four instances, the gap between the time the virus was first recognized and a second, more dangerous wave swelled was about six months. It will take a minimum of four months to produce vaccine in any volume, possibly longer, and much longer than that to produce enough vaccine to protect most Americans. The race has begun.

More: http://www.nytimes.com/2009/04/28/opinion/28barry.html

The Great Influenza by John M. Barry

The flu could fizzle out or it could go underground and return more virulent. Flu viruses are unpredictable. That is why the CDC and the WHO are monitoring this new virus so carefully.

[aquart]

1. Yep. Pray for fizzle.

Or that you catch it in the first wave.

[valerief]

2. They should monitor it carefully. The MSM shouldn't be pulling this Apocalypse crap, though. nt

[Ladyhawk]

9. I don't have TV anymore, so I'm not being subjected to the hysteria.

I've read books and articles about flu viruses and felt it was important to share this bit of info. I heard that the idea of "waves" and virus adaption to humans hasn't been discussed in any detail.

[seemslikeadream]

3. That is the problem

[Hannah Bell]

4. "Passage" can also lead to lower virulence. So?

[Ladyhawk]

8. In the last four pandemics, the second wave was more virulent.

That didn't matter much for the Hong Kong flu, which was mild all around. It also doesn't necessarily mean a second, more virulent wave will come this time. It's just something to monitor.

As quoted above:

"In all four instances, the gap between the time the virus was first recognized and a second, more dangerous wave swelled was about six months. It will take a minimum of four months to produce vaccine in any volume, possibly longer, and much longer than that to produce enough vaccine to protect most Americans. The race has begun."

[dalaigh lllama]

5. I read about the 1918 flu -- this does explain it well

I don't think many understand why they are trying to contain it now when it's so mild. I think the problem is that the more it spreads, the better the chances of a virulent strain mutating and coming back this fall in lethal mode. Of course, if they are successful in containing it so it has fewer chances to mutate, folks will be complaining about how they overreacted this spring.

[Ladyhawk]

10. Yes. One thing that is completely different from 1918...

...there aren't as many soldiers living in crowded conditions. Cantonments and trenches provided tinder for the virulent strain. It was awful.

[Quantess]

6. "Passage through humans"

The first time I skimmed over that warning, somewhere else, I took it to mean a literal passing...through human digestive systems.

[Avalux]

7. I think the unpredictability of viruses is why the WHO and CDC are being so serious.

We really don't know what this virus is going to do. The 1918 virus visited humanity in three waves; the second being the worst. We just don't know how this current new virus will play out but given what we know, it's possible it might fizzle them come back stronger.