Vive la Resistance to Flu
Debora MacKenzie
Some people may not need a second flu shot this season to be immune to swine flu
Vaccinating people against swine flu may be a lot easier than anyone dared hope, as it turns out that people have an unexpected degree of immunity to the pandemic now sweeping the world.
A seasonal flu in the same H1N1 family as the pandemic virus has been circulating since 1977, but until now it was thought that this seasonal virus did not induce immunity to the pandemic strain. This was because the pandemic virus spread faster than would be expected if there were widespread immunity to it, and because antibodies to the seasonal vaccine do not cross-react with it.
This looked like bad news for pandemic control. When people have no pre-existing immunity to a flu virus, they need not just one but two doses of vaccine several weeks apart, making it very hard to immunize many people in time to protect them. But in September, the Swiss firm
The Chinese vaccine firm Sinovac and the French firm Sanofi report similar results.
"Somehow people's immunity has been primed," says
These antibodies can't be the whole story, though, because people without them also responded swiftly to the vaccine. Seasonal H1N1 infection may have primed another part of the immune system, called cell-mediated immunity, which may not prevent infection but limits the severity of the disease. This could be why the pandemic has spread fast but remained mild in many people, though not all.
More good news comes from computer modelers at the
The immunity that many people now have means that this priming may not be needed, and that just one shot of vaccine could result in full immunity.
H1N1 and Its Descendents: Where This Pandemic Flu Came From - and Where it Might Go
Harvard Health Letters
Already, 2009 is not a typical year. We're in the midst of a flu pandemic caused by a virus that first emerged in Mexico in mid-February. Billions are being spent on preparedness plans. And millions of Americans may line up this fall to get two kinds of flu vaccines, one for the regular seasonal flu that comes around every winter and another for the pandemic strain. So far, the 2009 pandemic has been more widespread than lethal.
Air Kisses, Hugs, and Other Ways to Avoid Getting Swine Flu
Deborah Kotz
In an effort to contain swine flu, the French Health Ministry this week called for citizens to avoid "all direct contacts between people and particularly with sick people," which means no kissing or shaking hands.
4 Flu Vaccine Doses for Kids This Fall -- but Where and When
Nancy Shute
This may go down in history as the most confusing flu season ever, given that a vaccine for the new H1N1 swine flu isn't yet available, but the plain old seasonal flu vaccine is. Talk about a recipe for pandemonium at the pediatrician's office!
Seasonal Cold or Swine Flu? Moms Face Tough Calls
Deborah Kotz
I sent my 11-year-old son to school today with a stuffy nose and mild cough, as I've done countless times in the past. Now, though, I'm wondering whether I should have kept him home. How do I know it's really a garden-variety cold and not the swine flu?
Still Confused About Swine Flu Shots? Kids Under 10 Will Need 2
Nancy Shute
The National Institute for Allergy and Infectious Diseases made it easy to think that all children will need just one swine flu immunization, but that's not true. The younger a child is, the less well his or her immune system responded to the swine flu vaccine in clinical trials. So children under age 10 will need two doses of swine flu vaccine, one month apart, according to the NIAID itself.
Better Ways Medicine Can Beat Back Swine Flu
Bernadine Healy M.D.
Yes, today's swine flu outbreak could change quickly. But it's time to give up the ghosts of 1918 that so haunt our medical thinking. Our challenges today are not what they were when we had nothing to offer but are more about knowing just what to offer, when, and to whom. This swine flu pandemic promises to teach numerous lessons that will inform future crises. Some are already evident
(c) 2009 New Scientist magazine