The year you were born predicts flu risk
directorsblog.nih.gov
directorsblog.nih.gov
And if you factor in that they were studying mostly Asian countries, Egypt, and Germany, there might be even more discrepancies to account for.
http://www.ucdmc.ucdavis.edu/transplant/livingdonation/donor...
I'm curious about the idea of flu viruses completely replacing each other. Do they interact or compete for resources in some way? Could we design a very mild flu which would replace other variants?
When you have similar strains of a bacteria or virus, they can all cause the same immune reaction (which is how vaccines work) but tiny genetic variations in each strain can also drastically change how effective the reaction is against variant. Since bacteria/viruses reproduce very vast and the immune system is very good at its job, you essentially get an accelerated arms race that heavily favors the survival of the fittest. Even one part per million difference in probabilities is almost enough to guarantee the dominance of a single strain.
The question is why did this new variant "completely replace" the old ones in the population, instead of just operating in parallel?
The only thing I can think of is that the old flu variants were in decline already due to herd immunity, but the article seemed to imply there was more to it than that.
it seems that having just 2 varieties representing those 2 hemagglutinin groups can already provide pretty good protection.
I really hate getting the flu ... I hate feeling terrible for 12-24 hours, I hate missing multiple workouts ... hate hate hate.
However, in recent years I've stopped my (seemingly ineffective) efforts to avoid the flu at all costs and further have started to appreciate the positive effects that getting the flu every 12-18 months might have.
In an otherwise healthy adult, what puts your immune system through it's paces - what gives your immune system a workout - like having the flu ?
What happens to my immune system if I don't give it that thorough workout every year for ... say ... 40 years ? What kind of immune system do I end up with at the other end of avoiding the flu for a large chunk of my life ?
Related to that, what else gets killed every 12 months when my temperature goes up to 102 or 104 for half a day ?
That's not how immune systems work. This isn't just a round of going to the gym. Getting a vaccine also gives your immune system a chance to learn and react, but without the severe degradation of your condition and the significant risk of secondary infection.
> What happens to my immune system if I don't give it that thorough workout every year for ... say ... 40 years ?
First of all, you run less of a risk of getting secondary infection when your immune system is weakened. Secondly, you run a higher risk of transmitting the flu to people who can't be vaccinated (for example, babies or the elderly), putting their lives at risk.
[Herd immunity: https://en.wikipedia.org/wiki/Herd_immunity]
> Related to that, what else gets killed every 12 months when my temperature goes up to 102 or 104 for half a day ?
That's the opposite of how your immune system works. While your system is focussed on fighting off one infection, it's less able to deal with secondary infections. You can end up spreading your system too thin and your health can deteriorate much more rapidly.
[Secondary/opportunistic infection: https://en.wikipedia.org/wiki/Infection#Primary_versus_oppor...]
In other words, not getting a vaccine is unwise both for yourself and for other people.
Citation please. I'm somewhat skeptical about GP's viewpoint, but equally skeptical that you can so confidently dismiss him, given the number of things we still don't understand about the immune system. For example, doctors still haven't managed to cure any autoimmune illness, even though we've studied them for quite some time.
Full disclosure: I suffer from autoimmune illness, and every time I ask me doctor about my condition, the answer is often 'we still haven't figured it out'. The sheer complexity of all the different immune cell types, cytokine signaling, antibody production, etc. is mind-boggling, and is the product of millions of years of evolutionary arms race.
In particular, vaccines predispose your immune system towards an immediate Th2-type (humoral) response, while acute viral infection prompts first a Th1 (intracellular) response, then a Th2 response during recovery.
A strong Th1 immune response is generally more effective against viral illnesses, so it's possible that if you had a different concurrent viral infection, getting the flu could encourage your body to clear both at the same time.
Also, https://en.wikipedia.org/wiki/Hygiene_hypothesis
> you run less of a risk of getting secondary infection when your immune system is weakened
That's true, but you haven't shown that getting the flu weakens your immune system.
> While your system is focussed on fighting off one infection, it's less able to deal with secondary infections.
Your citation doesn't actually support your claim. Latent subclinical infections are real, and it's possible that acute febrile illness can stimulate the immune system to go after other bugs that have been hiding or dormant.
There is some evidence that ongoing viral infections can weaken your bodies defenses against bacterial illnesses and vice versa.
I got the flu 10 months ago as a healthy male in his late 20s, the first major illness I've had since I was 11. 102+ fever for over 5 days and then developed a pneumonia coinfection which knocked me out for another week. It was not just an inconvenience, it scared me being that sick.
The hospital I went to in Philadelphia to get treatment for the pneumonia said they had several young adult patients who were otherwise generally healthy in intensive care due to the bout of flu going around and related complications/coinfections. The flu kills people -- between 3,000 and 50,000 per year in the US [1]. Count yourself lucky that your experience with the flu has been as you described, if it was even the flu at all.
[1]: http://www.cdc.gov/flu/about/disease/us_flu-related_deaths.h...
12-24 hours seems more like a "stomach flu" (Gastroenteritis) or a cold (rhinovirus), neither of which is influenza (aka "the flu").
According to the CDC: "Most people who get influenza will recover in several days to less than two weeks, but some people will develop complications as a result of the flu."
As others have covered and explained better than I can, the immune system isn't a muscle that needs an annual workout, especially given the risks of serious complications like pneumonia.
My wife is a surgeon and works with legitimately sick people every day. The result of which is she typically has no sympathy for me when I get sick. As in "Can you please make less noise when you are vomiting. I'm trying to sleep here". No sympathy, except when I got the flu. I've never seen her that worried, because she knew from experience that the flu can kill you.
Parent almost certainly had a cold if it was gone in 24hrs.
Look up cytokines storms. https://en.m.wikipedia.org/wiki/Cytokine_storm
A strong immune system can be a liability. When I was nearly hospitalized with the flu, I was in my late twenties and in the best shape of my life. Which is why I must repeat myself, DO NOT FUCK WITH THE FLU.
It's like sparring at 1/2 power with full pads vs. getting into a full on street fight. Sure, the street fight will give you a slightly more real practice session, but at what cost? There is a lot of collateral damage there.
Cancer will really give your immune system a work out.
Getting a vaccine is training for the big game. Getting the virus is the big game. Show up to the big game without proper training and you might win, have a few broken ribs, a new face, a limp, or you might just straight up lose.
Getting vaccinated makes your body capable of enlisting otherwise non-present antibodies.
It seems like there would be so many potential factors that could be causing a distribution like this. But I'm not a scientist, so dunno.