Free Republic
Browse · Search
Topics · Post Article

Skip to comments.

Old seasonal flu antibodies target swine flu virus
Nature News ^ | 21 May 2009 | Heidi Ledford

Posted on 05/23/2009 1:26:09 AM PDT by neverdem

Lab results could explain why young patients are hardest hit by current H1N1 strain.

Antibodies against some seasonal flu strains from prior years may be active against the new H1N1 swine flu currently circulating the globe, a recent study reports. The findings suggest an explanation for why swine flu appears to infect the young more often than the elderly, who are normally more susceptible to seasonal flu viruses.

Only 1% of swine flu cases in the United States are in people over the age of 65.Only 1% of swine flu cases in the United States are in people over the age of 65.CDC

The study, published today in the Morbidity and Mortality Weekly Report, analyzed blood samples taken from 359 participants in flu vaccine studies conducted from 2005 to 2009. 33% of the samples from people over 60 years old had antibodies that reacted with the swine flu virus, as compared to 6%-9% of the samples from people aged 18–64 years, and none of the samples taken from children 1.

The results match the apparent current epidemiology of swine flu infection, says Anne Schuchat, interim deputy director for the Science and Public Health Program at the Centers for Disease Control and Prevention (CDC) in Atlanta. Most cases of swine flu have occurred in people who are under 60 years old, and only 1% of confirmed swine flu infections in the United States were in patients over the age of 65.

Nevertheless, the results should be interpreted with caution, Schuchat urged in a press briefing today. Researchers have shown that the antibodies react with the virus in test-tube assays, but they have not yet shown that the antibodies can fend off the virus in animals or people. "Whether this particular assay will pan out over time as predictive of clinical protection, we can't say," Schuchat said.


For the study, CDC researchers used two tests to determine whether antibodies in the blood were active against the swine flu. One test studied the impact of the antibodies on growth of the virus in cell culture, and the other assayed the ability of the antibodies to inhibit an important viral protein called hemagglutinin.

The results indicated that vaccination against recent H1N1 seasonal flu viruses did not generate antibodies that react with the swine flu virus. But exposure to older seasonal flu viruses or vaccines — perhaps dating back to the 1950s or earlier — may have yielded cross-reactive antibodies in some older study participants.

Although the results have not yet been confirmed clinically, the researchers used standard techniques that are often used in preclinical studies of flu vaccines, says Ralph Tripp, a viral immunologist at the University of Georgia in Athens. "The reality is, there does appear to be a substantial level of cross-reactivity in those adults aged 60 years and older," he says.

Genetic analysis of the new swine flu virus has shown that it differs dramatically from previous seasonal viruses. But Tripp notes that H1N1 viruses were circulating in swine during the 1940s and 1950s and could have mixed with seasonal flu viruses during that time. Exposure to these viruses could have launched an antibody response that continues to protect individuals against today's swine flu.

Meanwhile, Schuchat notes that it is possible for immune responses to the current swine flu and past seasonal viruses to overlap, despite the genetic dissimilarity. "We don't have a particular virus that we're thinking about," she says, "but we're wondering if there might have been some viruses around in the '30s, '40s and '50s that might be immunologically similar to the one we're seeing now."

TOPICS: Culture/Society; Government; News/Current Events; Testing
KEYWORDS: antibodies; flu; genetics; h1n1; influenza; swineflu; virology
Antigenic and Genetic Characteristics of Swine-Origin 2009 A(H1N1) Influenza Viruses Circulating in Humans
1 posted on 05/23/2009 1:26:09 AM PDT by neverdem
[ Post Reply | Private Reply | View Replies]

To: Mother Abigail; EBH; vetvetdoug; Smokin' Joe; Global2010; Battle Axe; null and void; ...
Genetic analysis of swine flu virus released

micro ping

2 posted on 05/23/2009 1:36:24 AM PDT by neverdem (Xin loi minh oi)
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem

Thanks once again to Neverdem, always on top.

To ANY internationals and BDS citizens I pose the following question:

How proactive is your government stocks against a possible viral outbreak?

Well what ever you say, there is absolute proof that Clinton defunded the CDC stockpiles - yea he probably sent all that “wasted money” towards things that were really working, like public education. I digress, but I do know that the Bush admin spent (wisely) towards something that mattered.

If there were any justice in this lifetime, Libtards would be the only persons afflicted by that which the demoncrats defunded. Don’t thank me, thank Clintoon.

3 posted on 05/23/2009 1:57:48 AM PDT by ChetNavVet (Build It, and they won't come!)
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem
Suggest, maybe, almost, and predict.

All the key words are there from the GW crowd who have no freeking idea.

Incredible, even the flu is political now.

4 posted on 05/23/2009 2:02:28 AM PDT by MaxMax (America's population is 304-Million. Obama must punish America for the other 4.7 Billion)
[ Post Reply | Private Reply | To 1 | View Replies]

To: MaxMax
ER, one exception. now they look to the 30-40s. With GW they only look back to the
cycle that stimulates their consensus.
5 posted on 05/23/2009 2:05:29 AM PDT by MaxMax (America's population is 304-Million. Obama must punish America for the other 4.7 Billion)
[ Post Reply | Private Reply | To 4 | View Replies]

To: 2ndreconmarine; Fitzcarraldo; Covenantor; Mother Abigail; EBH; Dog Gone; ...

Ping... (Thanks, neverdem!)

6 posted on 05/23/2009 4:57:15 AM PDT by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing.)
[ Post Reply | Private Reply | To 2 | View Replies]

To: neverdem

It’s gonna be hard for U.S. workers to pay for Obama’s social engineering programs when the productive members of society have succumbed to the virus formerly known as swine flu.

7 posted on 05/23/2009 5:07:20 AM PDT by NautiNurse (Obama: A day without TOTUS is like a day without sunshine)
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem

Thanks, neverdem!

8 posted on 05/23/2009 5:47:22 AM PDT by MaggieCarta (We're all Detroiters now.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem
You bring up this Swine Flu crap one more time, never... Photobucket and I'm gonna go medieval on your ass!

And you don't... Photobucket want that, never! You don't want it, EVER!

9 posted on 05/23/2009 6:07:54 AM PDT by Bender2 ("I've got a twisted sense of humor, and everything amuses me." RAH Beyond this Horizon)
[ Post Reply | Private Reply | To 1 | View Replies]

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794 is powered by software copyright 2000-2008 John Robinson