Mystery of the pandemic flu virus of 1918 solved

[Jim__]

From Medical Xpress:

...

[center][/center]
[center]The researchers found a remarkable overlap between death rates in various age groups in 1918 and childhood exposure to an H3 influenza virus mismatched in its major antigenic protein to the H1 virus of 1918: age groups with the highest percentage of individuals exhibiting H3 antibodies fared the worst in 1918, and the death-by-age curve closely tracks the peaks and valleys of H3 antibodies in cohorts born before, during and after the 1889 H3 pandemic. Credit: Michael Worobey[/center]

[hr]

"Ever since the great flu pandemic of 1918, it has been a mystery where that virus came from and why it was so severe, and in particular, why it killed young adults in the prime of life," said Worobey, a professor in the UA Department of Ecology and Evolutionary Biology. "It has been a huge question what the ingredients for that calamity were, and whether we should expect the same thing to happen tomorrow, or whether there was something special about that situation."

Worobey and his colleagues developed an unprecedentedly accurate molecular clock approach and used it to reconstruct the origins of the 1918 pandemic H1N1 influenza A virus (IAV), the classical swine H1N1 influenza virus and the post-pandemic seasonal H1N1 lineage that circulated from 1918 until 1957. Surprisingly, they found no evidence for either of the prevailing hypotheses for the origin of the 1918 virus – that it jumped directly from birds or involved the swapping of genes between existing human and swine influenza strains. Instead, the researchers inferred that the pandemic virus arose shortly before 1918 upon the acquisition of genetic material from a bird flu virus by an already circulating human H1 virus – one that had likely entered the human population 10-15 years prior to 1918.

"It sounds like a modest little detail, but it may be the missing piece of the puzzle," Worobey said. "Once you have that clue, many other lines of evidence that have been around since 1918 fall into place."

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[GusBob]

1. would it matter that it was WWI?

and people of that age group would've been in groups together? Or was it both males and females equally?

[Warpy]

4. It started raging through barracks

as soldiers waited for their discharge paperwork to come through and from there it spread to the general population.

One story I read was of 4 women who played bridge in the evening and were all dead by morning. It struck quickly and killed quickly, often within hours of "my throat feels scratchy" to dead.

What was amazing is how quickly it spread around the planet in the days of slow transportation by ship.

[Rozlee]

12. My mother lost four siblings to it in three days.

Only one was in his twenties, within the age demographic mentioned. The other three were early to late teens. They all lived in Mexico and the dead were buried in burlap shrouds.

[Warpy]

15. There is no shame to a burlap shroud.

They were ahead of their time, there is no reason to waste wood on a coffin and now "green" burials are making a fortune for undertakers who will do them.

Back then, it was a combination of haste and overwhelmed burial services driving up the cost of even a simple pine coffin.

I don't remember any stories from the family about the 1918 flu. I think both sides were lucky enough not to contract it. In any case, they practiced Catholic birth control and didn't marry until they were into their 30s and 40s, so they were out of the demographic by 1918.

Others weren't so lucky and here in the US, the number of deaths was enough to drive overall life expectancy statistics down by a decade.

Your mom must have been devastated. I can't imagine that level of loss.

[KT2000]

5. troop movements

and soldiers returning home spread the disease. Groups of soldiers suffered the outbreak.
The whole world was affected by this flu except for one tiny island - for get the name though.

I believe the age group noted is for those who had the worst cases. Many people had the flu but not all died. For some it was like any other flu.

[Jim__]

10. The graph is not very clear.

The correlation looks extremely close; but the different lines may not be drawn against the same scale.

[greatauntoftriplets]

2. Interesting.

My grandfather died of Spanish flu in 1918 at age 34. He was an undertaker who had been embalming dead soldiers at Camp Grant near Rockford, IL, and caught it.

[eppur_se_muova]

9. Belligerents on both sides suppressed any news reports of the severity of the disease ...

only in Spain did the papers report accurately, and thus it came to be known as the Spanish flu. Spain was neither the source of the outbreak nor the first country where it was reported or identified.

Nowadays, the convention is that the first city where the disease is reported gives its name to the disease.

PS: A salute to your grandfather. Army doctors suffered an astonishingly high casualty rate during that outbreak, but I know of no reports of any who tried to shirk their duties. Many kept working until they were bedridden themselves, then went back to work immediately if they recovered.

[Mnemosyne]

3. Very interesting. nt

[Baitball Blogger]

6. So, antibodies for one virus, made you more susceptible to another one?

[Jim__]

7. I don't read it that way.

I think it is that the group that was most vulnerable did not have previous exposure to an H1 virus. If your previous exposure was only to H3 virus, that did not give you very effective immunity against an H1 type virus.

[Baitball Blogger]

8. That sounds logical.

But it also suggests that the H1 virus that took them out was pretty potent.

[Avalux]

11. This has been hypothesized for awhile - fantastic they finally have proof.

It would have been a pandemic no matter what, but that select group of people who were never exposed to H1 but H3 instead were completely defenseless to the virus.

[ashling]

14. Tof my mom's older brothers and sisters died

I'm not sure if they all had the flu, but I know that "little Annie" the youngest did.

My mom was just a baby

[merrily]

13. Between the flu and the war, so many millions died.

Yet, the planet is overpopulated. I sometimes wonder what the world's population would be today if that were not so.


That is to no way suggest that I rejoice in anyone's death, let alone millions of people. It is only to underscore how severe the overpopulation problem is.

[hedgehog]

16. Thank you for spotting this article!

IIRC - hundreds of men died on some of the troop ships leaving the US for Europe -they were packed like sardines for the voyage and the flu just swept through the group.

My grandmother was a young teenager in rural County Mayo back then, but remembered all the friends she lost to her dying day.She never missed getting her flu shot, even though they usually made here sick.

[starroute]

17. My grandmother died of the flu in January 1919 - she was 29

It was just a few days before my dad's fourth birthday. He always said he had no memory of her -- just of holding his little brother's hand afterwards and feeling that now he had to take care of him. I can't imagine what that was like.

[defacto7]

18. My Father was one of

11 children on a farm in Kentucky during the epidemic. Many in their vicinity died but only his 12 year old brother died of it in their family. I have always wondered how a large family like that could have only one death from the epidemic. They were all exposed and a couple more of them had that flu and lived. Their ages ranged from infant through the 20s and my Dad was 9. It seemed to be a virus that was pretty particular of its victims.

[SheilaT]

19. The Great Influenza

by John M. Barry is an amazing read.

One reason the 1918 influenza epidemic spread as it did was that it got started in Kansas in soldiers' barracks. They were crowded together, young men who quite literally had never been off the farm, who'd had very few contagious disease and hence somewhat incomplete immune systems. And then the U.S. Army kept on shipping these very young men, just as soon as they'd been exposed to the flu, off to other army camps, onto crowded troop ships, off overseas. Doctors kept on trying to persuade them to not do this, to no avail.

The book also describes the change that occurred in American medicine around that time, taking it from being not very good, with badly trained doctors, to the finest system in the world in a very few years. Bad medical schools were closed. Doctors were now required to learn basic science, and so on.

Excellent book.