In New York City, an illness termed "mild" for many has killed 7 and put 300 in the hospital. A preliminary analysis of about half of those hospitalized, most (82%) were said to have some underlying medical condition. That's common with flu, but it's also a reminder that one of five were otherwise healthy, and unusually for flu, most of them relatively young (mostly under 65). Similarly, the deaths also had underlying medical conditions but were relatively young (median age 43). The two most recent deaths were in the mid 40s.
So not being old is one risk factor. What does "underlying medical condition" mean?
So far, the most common risk factor in New York City has been asthma - an underlying risk factor among 41% of the New Yorkers hospitalized for H1N1 flu. Other important risk factors include being less than 2 years of age (18% of hospitalized patients), having a compromised immune system (13%), having heart disease (12%), or being pregnant. The Health Department recommends that people with asthma, or any of the other conditions listed here, to call a doctor right away if they develop flu-like illness. [snip] Anyone feeling ill can take his or her temperature with a home thermometer. A temperature of 100.4 degrees is a fever. If the fever is accompanied by cough or sore throat, the condition qualifies as flu-like illness. (New York City Department of Health)
While emergency room visits are down from their peak of a week ago, a time when doctor visits for flu were also increased 15 times over what was expected for this time of year, it was clear that flu was still spreading in the city, with visits still higher than normal. Attendance rates in school were still below average although also up from last week. All but 4 of the 50 schools that were closed are now open. In other words, there may be just as much flu out there now as last week, but people are adjusting to it.
So how much flu is "out there"? Not an easy question to answer. One way to get at it would be to do a random sample of New Yorkers and ask them if they've had flu-like symptoms. To get an unbiased estimate (i.e., a guess that on average is the same as the true average) would require that any New Yorker have an equal chance of being chosen for the survey. But there is no "master list" of everyone in New York City, so the Health Department used an old but conventional sampling technique called random-digit-dialing for the purpose. In essence this means randomly selecting residential telephone numbers and phoning people to ask them questions. Today, however, this can only be used with land lines (no cell phones) and you have to have a land line phone number to be in the sample, so as a representative sample it's imperfect. Since there are other causes of "flu-like illness" besides influenza infection, and not all those infected with the influenza virus have classical symptoms (or any symptoms at all), this is another problem. And of course the respondent has to remember they had the symptoms, which if they were mild might have been forgotten or disregarded or remembered now as something different than they were (recall bias). Nonetheless, 1000 people have been questioned this way and the results are being analyzed. With all the problems, it will be interesting to see what they show.
All this goes to show how epidemiology in the real world can be much more difficult, uncertain and complicated than the simple questions it is trying to answer -- like how much flu is there in New York City? -- would seem.
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well said
I expect you've already spotted this, but Google have started a new website about flu trends. It will be interesting to see how their results compare with those of the survey you mention.
They explain how they get their results:
"We have found a close relationship between how many people search for flu-related topics and how many people actually have flu symptoms. Of course, not every person who searches for "flu" is actually sick, but a pattern emerges when all the flu-related search queries are added together. We compared our query counts with traditional flu surveillance systems and found that many search queries tend to be popular exactly when flu season is happening. By counting how often we see these search queries, we can estimate how much flu is circulating in different states and countries around the world. Our results have been published in the journal Nature."
That isn't necessarily all that good news.
We are a fat, old, sedentary society. How many people have "underlying conditions". As a boomer, most of my personal peer group seems to have an underlying condition of one sort or another.
A lot of people are alive today with underlying conditions because of modern medicine.
With a lot of flu infections and a lot of "underlying conditions", the hospitals are still going to be filled up.
The United Nations international school closed yesterday.
I don't think anyone has any idea how much flu is out there. That is, I think they've stopped caring recently. People have very short attention spans, and it's hard to visualize what it means in terms of personal risk of contracting the flu when you hear that a few hundred people have it in a city the size of NYC.
I mean, if I ride the subway, will I catch it? If I hang out with a coworker who lives a few blocks away from the first school that was closed, will I catch it? No-one's even worried enough to start wearing face masks in public, although I HAVE seen quite a few Asian tourists wearing them. They have a better grasp of the situation, I would say.
Sylvia,
http://www.cdc.gov/h1n1flu/masks.htm
I will not be wearing a mask or respirator on my visit to NYC this weekend.
Drat it, will someone help me with this? I'm arguing with someone who says this flu is "just a new strain" like the ones they vaccinate for. I pointed out that no, it's very different, not a recombo of human flu but a recombo of swine and avian and human flu, which is why people don't have immunity.
Her reply:
"How do they know thereâs no resistance in the population? Thereâs almost no way to trace that.
All flus are avian derived, the ability to infect other groups is acquired."
The answer I have is because that's how flu strains work, but obviously that isn't clear.
Anyone have a nice short answer (I know) for "but it's just another strain everybody's blowing it out of proportion"?
mandrake: You are correct. First, this is an all-swine virus (see here. As for residual immunity, we dealt with that here. Of course you could also refer your friend to CDC if she is not impervious to evidence.
Genetic sequencing and the epidemiology (I am an epidemiologist by profession) show this is not a seasonal but a pandemic strain. This is evidenced by the marked left shift of the age distribution. Only a few percent of confirmed cases are over 65, very different than seasonal flu. The hardest hit age group is 5 -24, also highly unusual for seasonal flu. The "everybody" blowing it out of proportion presumably includes CDC, WHO and every state health department. And on the other side of the argument and their credentials?
We've had a high rate of illness in our area that includes high fever (104 in adults, higher in kids), aches, pains, etc, and swollen glands ... no cough or sore throat. I saw in the California study that only 77 percent of hospitalized patients had a cough. Is it possible, you think, that this could be swine flu even in the absence of respiratory symptoms? If not, it's a local epidemic of something else, because there are a lot of kids (and a few adults) sick around here right now.
I'm in MI, btw, but not in a county that's been heavily affected (5-6 reported cases).
Curious: It certainly could be. Only some testing would determine if it were.
Revere I believe the quality control of the following datas are sound.
Network sound datas
Confirmed cases admitted in hospitals 433
Age 10-19 = 28%
Age 40-64 = 37%
55% are women
7 Days prior to symptoms for confirmed cases
39 admitted on 117 confirmed cases
Trip in high density zone 11% admitted
Epidemiological link 11%
Unknown the rest
Fever and Coughing have BOTH average of 92% in symptoms
Fever, cough, Throat aches and Myalgia in 41% admitted
The hospitalisation time average is of 3,7 days
Communications is getting better Reveres Taïwan Centers for Diseases Control reached out and pro-actively relay a confirmed H1N1 infected in our Region.
No death
Snowy
Isn't it strange that NYC Dept of Health keeps saying 65 years of age and over IS A RISK FACTOR!
nycflu: Yes. They do it, I guess, because over 65 is a risk factor for seasonal flu complications, but apparently not for this novel flu, as you point out.
We live in Southern NJ. According to the CDC map, A/H1N1 is considered 'widespread' in NJ. My oldest daughter, 37, has had intrinsic asthma since childhoold and had rapid onset classic flu-like symptoms in the past 24 hours. She saw a local doc today who told her it was strep but didn't test for it,could be lymes disease or mono-doubt that with such a rapid onset fever, headache, exhaustion, severe muscle and bone pain, but it couldn't be flu! She tested her for mono and lyme, not for flu or strep and sent her home on doxycycline! (She has no penicillen allergy) Now my daughter thinks I'm crazy for voicing my concern it could be flu. I was able to get her a script for Tamiflu and asked her to take it anway.
I wonder what filters down to the PCP's offices from the county and state DOHs.
Grace: Aaaargh!
Revere: I was tested when I had it -- nasal swab, but I couldn't tell you what type -- and it was negative for any kind of flu. We've had kids at school as long as a week with it, though, so that's why I question.
Also, in various reports, it seems like there's a slightly higher incidence of women being hospitalized? (Like in the comment above, though I've seen it elsewhere.) Do you think there's anything to that?
Doctors are people too. If the public thinks this flu is over for the summer, then why not the docs? Would make for an interesting article to interview doctors and see if they are even looking.
btw, what message are doctors getting from their state or county health departments? What are they being told?
I work at a local health department, and still routinely field calls from doctors' offices on whether they should send off specimens to our state lab for patients testing postive through rapid flu tests. Our state HD has prepared testing and treatment guidelines that addressed those questions a few weeks ago, and which I've dutifully passed along to my local primary care physicians as their conduit, but considering that I'm still getting these kinds of calls, clearly not everyone's been reading what they've been given.
At the moment we're asking physicians to limit requests for testing by our state lab to cases involving clusters of influenza-like illness, particularly those in healthcare facilities, schools, jails, etc., or for cases involving patients who've required hospitalization. We still encourage our sentinel physicians to submit specimens from any suspected case (within reason).
I've easily seen more positive swine flu test results in the past two weeks than in the first two weeks since this began, but that might be a consequence of specifically requesting samples from clusters. While we're no longer experiencing the frenzied activity of nonstop phone calls, press conferences, back-to-back meetings (and even some epidemiology, time permitting), dealing with swine flu at the local level is still taking a significant chunk of my time. I'd really like to hope it dries up and blows away for the summer, especially since I'm in serious need of a vacation at this point, but I'm not ready to put any serious money on it.
Curious: A negative rapid test makes it less likely you had the flu but not unlikely, as these tests are only about 50% sensitive, i.e., they are right about people who have the flu only about half the time. It also requires that the swab be properly taken. A nasopharyngeal swab has to go all the way to the back of the throat, through the nose. Uncomfortable and not always done properly. So I wouldn't bet the ranch you didn't have the flu, just on the basis of that test.
Oh my...I do not live near New York, but when this all started...our family took a huge step for prevention! Our entire family is now on Vidazorb probiotics so that our bodies have an edge in fighting off bugs like these! Probiotics help boost immunity and as a mom, I feel good knowing that we are taking some precautions :)
Thanks, Revere. My nasal swab was simply a q-tip in the nostril, more or less, so I suppose there's no way to know for sure. And since I didn't have any respiratory symptoms (no mucous in the nose), I wondered if that would affect the sensitivity of the test.
At the ER, they brushed off swine flu concerns. "It's just the regular flu," the nurse told me. "All hype." But I'm not buying it :).
So is the gestation period... mentioned above ...really an average of 1 week ? Or is this just the maximum time.
If person A catches becomes exposed...how fast could person B catch the bug from person A (or to put it another way, do we know how long after infection that an individual becomes infectious) ?
Surely this stuff is known now...
Thanks for any info.
There needs to be more attention to schools as vectors for contagious illnesses.
Although over half my son's 3rd grade class (in NYC) was out with flu-like symptoms including high fever 2 weeks ago, the school nurse told me that there was no contagion in the school. The week before, about a third of the kids were out with diarrhea, strep, and conjunctivitis-- markers that infection control isn't' working.
I found out that school nurses are NOT supposed to report suspected cases of children kept home sick if the nurse is informed by parental report-- they are only to report when the child becomes sick at school. This effectively makes it impossible to determine clusters, especially if there is heightened awareness of symptoms during an epidemic.
In addition, there is no infection control in general in many schools. It is physically impossible to wash hands properly in any school I've visited. (E.g., when handwashing, the child has to turn the taps handles on with dirty hands, wash, then touch the same dirty handles. There is no education about how to avoid doing this and the physical set up makes it nearly impossible.)
This pandemic has been mild in its effects. But we shouldn't keep depending on luck. We need to teach children how to reduce the spread of germs at school. We need to make it part of the curriculum. And we need to make a few minor changes, such as foot-pedal operated sink taps.
What are the WHO pandemic levels for? It seems to me they are for two different things:
One to give perspective on a current disease outbreak compared to past ones so individuals can prepare themselves and make better judgements on things like school closings and such.
Secondly it is to trigger specific actions that we hope will mitigate the disease outbreak or curtail its spread or allocate scarce resources effectively. The specific action in mind in this are what ought to be driving the levels. That is, the levels should be, things like.
- get extra staff for emergency care in an area level
- close public activities with more than X people level.
...
- mobilize the National Guard to check on people level.
So The Announcements of going to a level is really a suggestion for a set of actions in an area. I would think that this would be regional. Right now this linkage seems more tenuous than it should to an outsider like me.
You are all annoying. I am an ER nurse who now has the flu because all of the otherwise healthy histrionics with MILD symptoms came to ER in droves and coughed in my face. Good times.