Here in the northern hemisphere, flu season generally starts in the fall and rapidly falls off at the end of winter. This past flu season, we had a "two-fer", with an initial dip in cases, followed by a spike in new cases attributable to the novel H1N1 ("swine") flu that emerged late last year.
The bimodal flu season of 2008-09
This is my first pandemic, and it's been fascinating. The sudden drop in cases at the beginning of summer was matched with a sudden increase in cases in summer camps and military installations. The high attack rate is particularly dramatic, although the virulence is not. Still, even with such a large number of people infected last season, most people have not yet been exposed, which leaves us open for a real whopper of a winter.
Influenza morbidity and mortality are tough to track because we don't test and report every case. The traditional method is using a rise in baseline mortality from pneumonia and influenza. Many who die from influenza actually die from pneumonia and the two diseases can look similar clinically. Also, pneumonia is relatively non-seasonal, so a spike in deaths from pneumonia+influenza that tracks with an increase in positive flu tests is a good indication of "excess" deaths due to flu. This number, which is usually around 35K to 40K per year, is not a measure of all flu deaths, but excess deaths above the usual baseline so actual flu deaths are probably greater.
A certain small percentage of flu patients die in a given year, so the more cases, the more deaths (assuming no changes in virulence). Now imagine that the curve of flu cases shifts upward significantly; even without a change in virulence, there will be an increase in flu-related deaths, so even a "mild" pandemic can stress our health care system. There are ways to prevent flu deaths---vaccination, of course, but also vaccination against pneumococcus which can help prevent deaths due to secondary pneumonia.
It's still not clear what will happen this year, but it's a reasonable bet that we're in for a bad flu season. In addition to the usual seasonal flu, the swine flu is likely to sicken a lot of folks. Here on the front line, we see this as a waiting room full of miserable people, coughing, slumped in chairs. In the hospital, ICU beds start to fill up with flu and pneumonia patients. The CDC tracks this data rather effectively, but a new tool is out there (of uncertain significance). Google has used search data to track the flu, and although it's not clear how good this data is, preliminary evaluation is promising. For the fun of it this year, I'm going to watch both google and the CDC, along with my own clinic and see what shakes out.
But in order to be able to carry out my day-to-day activities, I'm getting both my seasonal flu shot and my swine flu shot the minute they're available (and giving them to my family). I've also made sure my pneumococcal vaccine is up to date, and I've become even more compulsive about hygiene. Not only am I washing or using alcohol-based hand sanitizer like crazy, but I don't touch public doorknobs and other sources of fomites. This may seem a little compulsive (something I'm not often accused of) but it's cheap, easy, and probably effective.
So hang on, it may be quite a ride.
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You don't touch doorknobs? How does that work exactly?
I've come to terms with touching the knobs, but I have an assistant that follows me around with antisceptic wipes to use afterward. Now if I could just get over my fear of milk.
You carry and use tissues, joker.
A lab coat covers many sins...and allows you to push open doors and turn knobs
Can someone sterilise the / key, so that Pal will be able to touch it and close the i tag, please?
It wasn't me!!! It's site-wide!
Round these parts, Safeway's got the flu shots so the elder offspring and I got 'em this morning. Wish the swine flu shot were available...
A quick search of popular woo-meisters' sites (Mercola,Null,and NaturalNews)reveals their own *preparation* for the pandemic : first,terrify the woo-susceptible with tales of "forced, mandatory" vaccination,and "untested"(sic) vaccines "contaminated" with squalene and (gasp) thimerisol.Then,offer hope by selling videos and books about strengthening your "natural" immunity, as well as the supplements "necessary" to do so (and the odd gas mask here and there).Seriously folks! You can't make up stuff like this! But then again, they just did.
PalMD and Diane (and any other front-line providers):
Have you made any provisions for someone to take care of your families if they're down with the bug? In many cases that's going to sideline you as much as if you had it yourselves. A number of critical functions have been putting in place plans for that contingency -- the facility (an airport I know, for instance) has made cross-coverage part of their disaster planning.
Not that you wouldn't prefer to take care of PalKid yourself, Doc, but if the system is under overload strain ...
Something to consider.
What DC said.
Pal, I'm attending a conference on Continuity of Operations next month if you needs some tips...
Hey Pal MD, have you seen any of the articles about numbers of college students showing up with flu? I've wondered a couple of things. First, they are saying it's a big deal that 100 out of 35,000 students are suffering from ILI in the first week of classes. Is that really all that unusual? Second, it's odd that the H1N1 seemed to become the only flu that stuck around over the summer, and that the Southern Hemisphere didn't seem to have much "seasonal" flu other than H1N1? I'm curious about the mechanism whereby a single flu species can seem to "out-compete" all the others. Have you heard much about that?
Oh, I forgot to say that I'm thrilled that colleges are taking H1N1 so seriously and preparing for it. I just hope that people adopt better awareness of public health long term rather than letting it fall by the wayside next year. After all, it's never a good idea to go to work with the flu, swiney or seasonal. Frequent hand washing and hygiene are good ideas all the time too. Really, I can't imagine that anybody wants norovirus or strep throat, right?
In addition to doorknob avoidance, I've taken to riding escalators without ever touching the handrail. The downside to this is of course that I may be thrown to my death by a sudden stop of the escalator. Is it worth the trade-off?
#12: I always let my hand hover just above the handrail on an escalator or staircase - that way I can quickly grab it if I slip or the escalator stops. Even without the threat of swine flu I don't want to pick up the subway escalator germs, but since I fell down some stairs and broke a new cellphone (yep!) I have been more careful.
"A quick search of popular woo-meisters' sites (Mercola,Null,and NaturalNews)reveals their own *preparation* for the pandemic : first,terrify the woo-susceptible with tales of "forced, mandatory" vaccination,and "untested"(sic) vaccines "contaminated" with squalene and (gasp) thimerisol."
Yup, just had dinner with two nurses who were indignant that they might be "forced" to get flu shots. This was followed by recital of the "untested' gambit, and the claim that their patients have gotten the flu from the vaccine. Arrgh!
Sorry, took me a while to get to these excellent questions. I'm not sure why single strains tend to predominate, but it's not actually a "rule"...it's not unusual to have a few dominant strains during a particular season, and this year we are vaccinating for the "usual" epidemic flu and for the H1N1 pandemic.
Since schools and universities are only starting to get back in session, it's hard to say what impact we will see. It is unusual to see a spike in ILI this early, but there isn't yet a spike seen in CDC or google flu data. I suspect that after labor day we should have a clearer picture.