Effect Measure

Since I talk a lot about flu in my real life as well as on the blog, I get questions from moms and care givers who wonder when they should start to get worried about a sick child or relative. It’s context dependent, of course. The same symptoms that would be shrugged off at any other time take on a different meaning during a flu outbreak, especially when everyone seems uncertain about what is happening or what might happen. There’s nothing irrational about this. Infection with influenza virus is always potentially serious and when the young and healthy are in the cross-hairs even more so. Many other viruses can cause the same initial symptoms (“flu-like symptoms”), outside of flu outbreaks the likelihood those symptoms represent influenza infections is small. When flu is circulating in the community, however, the likelihood that the very same symptoms are from an influenza infection goes way up (the reasons can be found via an elementary application of Bayes Theorem in probability theory). So knowing when things are going sour is more important.

The question came up at one of CDC’s press briefings last week, and CDC’s answer seemed to me quite helpful, so I retrieved it from the transcript of the presser for posting here. The context is the extra risk from swine flu infection (or any flu, for that matter) for those with “underlying medical conditions.” There are two questions here. The first related to what constituted an underlying medical condition. Some of the examples cited seemed quite common (asthma, COPD, pregnancy), so much so that a large proportion of the population might be considered to have an underlying condition. So CDC’s Dr. Schuchat addressed the question of warning signs that indicate the person should seek immediate medical attention.

In children, signs that need urgent medical attention include fast breathing or trouble breathing; blueish or gray skin color; not drinking enough fluids; severe, persistent vomiting; not waking up or not interacting.; being so irritable that the child doesn’t want to be held; and flu-like symptoms improve, but then return later with a fever and a worse cough. Those are warning signs we physicians think about all the time, with respiratory infections. And they’re good to have in mind with this new influenza-like illness caused by the novel H1N1 strain. Just good things for parents to have in the back of their mind.

In adults, we look at another set of warning signs that suggest the need for urgent medical attention: difficulty breathing or shortness of breath; pain or pressure in the chest or abdomen; sudden dizziness, confusion, persistent or severe vomiting that doesn’t go away; and flu-like symptoms that improve, but then come back again with a fever or worsening of cough. (Statement by Dr. Anne Schuchat, CDC Press Briefing, May 28, 2009)

Once again, I think this is pretty good messaging. It tells many people exactly what they want to know: when should I start to get worried? Anybody who has had to deal with these questions appreciates the difficulty. You don’t want to falsely minimize something that later could turn out to be serious, but you don’t want to cause people to do things that burden the system when it’s not necessary. The best thing is usually to provide the best information you have. Most people then act rationally and responsibly.

I confess to be both surprised and impressed at how well CDC has handled this. We’ve had 8 years where CDC’s credibility was spiraling down the toilet faster than you can say Bush Administration. How well the same leadership would have acquitted themselves in this swine flu outbreak we’ll never know. But the new one, under Acting Director Dr. Richard Besser, has done an impressive job. If this continues under the new Director, Dr. Thomas Frieden, CDC well be on the road back to health. It couldn’t happen at a better time.

Comments

  1. #1 Snowy Owl
    June 1, 2009

    The Reveres, in a Nutshell,
    deliver us what are the warning signs.

    Sincere thanks

    Snowy

  2. #2 phytosleuth
    June 1, 2009

    A story out of New York on the recent death of a 2 month old infant says “The city has refused to release information about three of the other victims.”

    Is this because of HIPAA laws? If so, this law will harm many to protect the few.

    Read more: http://www.nydailynews.com/ny_local/2009/06/01/2009-06-01_babys_death_is_5th_linked_to_flu_in_city.html#ixzz0HC9T9XvI&B

  3. #3 revere
    June 1, 2009

    phyto; It could be HIPAA but probably state law. In most states cause of death is not public information.

  4. #4 Mathematician
    June 1, 2009

    Not trying to be funny here, but do other people get flu *without* pain or pressure in the chest? I’ve never sought medical attention for flu, but I’ve had those every time I guess myself to have had flu. Indeed, the conundrum that one has to keep breathing but every breath hurts is one of the defining features of the illness for me. Does this mean I am unusual and ought to have sought medical attention on each occasion, or that if people take notice of this then practically everyone with flu will seek medical attention?

  5. #5 Jody Lanard M.D.
    June 1, 2009

    Two compliments for the CDC in one day:

    I just posted this over at Flu Wiki, as part of a series called “Ministers in Wonderland”:

    Minister in the real world:
    Treating the public like grownups

  6. #6 phytosleuth
    June 1, 2009

    Mathematician, I know this is anecdotal, but I had chest pressure when visiting San Diego late March. Never had that before and it was a bit scary. Symptoms went away after a day of vitamin D3 and some flu herbs. My anecdotal experience, anyway.

  7. #7 James Bowery
    June 1, 2009

    Could you please pose the following question to Laurie Garrett of the Council on Foreign Relations:

    Hey, Laurie, why is the Council on Foreign Relations trying to cover up the fact that it is promoting the evolution of virulence world-wide

    http://www.medicalnewstoday.com/articles/151749.php

    by throwing red-herrings around like “xenophobia”, “nativism”, “racism”, etc.?

  8. #8 Farmer
    June 1, 2009

    Revere,

    You mention how well the CDC acting director has handled things. Well, I do agree, but let us not overlook Dr. Schuchat. She has performed consistently during multiple press conferences, staying calm, on message and relaying information in a clear, factual manner.

    I am very impressed. IMO she has been performing one of the most difficult jobs on the planet – well.

    Farmer

  9. #9 M. Randolph Kruger
    June 2, 2009

    Well before we get into the left wing mutual rub down lets remember that the CDC made no efforts to stop, slow or throw as required by the IHR’s. What happened to that? Politics?

    Sure, it might have done a bit to close the borders, but it was already in San Diego. Could they have quarantined it there or in Texas? Conjecture at best but there wasnt even an effort made. I for one would have at least tried… but its bad for PR. Need a body count to create a new department I guess.

    Can someone PLEASE tell me why it was a full week before we found out about it from the vaunted new CDC that Revere is so agoggle about? I have so many questions about how poorly it has been handled it would keep Waxman busy for years. How come NONE of the protocols were used or the criteria when met allowed for the public to find out about it?

    One good point? The good doctor was clearly not afraid to tell us the news, but they waited and its conjecture again whether it could have been at least slowed. But, cant have people dying until we have a titular head of CDC. Then instead of CDC, we get Napolitano. Hey baby, Obama is in charge and its all good. I didnt know Blanco had a cousin. I wonder if she had time to read the National Pandemic Flu Plan? Doesnt seem so. The good doctor obviously had but was being over ridden by all of the PTB. Very credible, why isnt she in charge?

    Well, here’s the rest of the story. Australia’s healthcare system is rising up onto the brink of collapse already..especially in the boonies. All elective surgeries are about to be held up. Yep, the well prepared Aussies and their UHC and all are about to stop even the NON elective surgeries out in the sticks. They are simply being overwhelmed with cases. They have 400 now, but the suspecteds are in the hundreds per day. I got a side line channel that it may be as many as 3500 now. Oz under the current administration has cut the total number of beds from 31,000 to 23,000 and is now underfunding their UHC by 8 billion…

    But would beds matter? Would UHC? I wondered last week about their susceptibility down there as I will here when the temps start dropping in August/September. You can read about bad here:

    http://www.news.com.au/adelaidenow/story/0,22606,25572062-2682,00.html

    But its good stuff to know what to look for and thank you Revere, but I STILL havent seen any single primary cause of death from any of the cases. Is it more the system shutdown (Daedalus-post) or is it something else? The “underlying” causes took out another two here in the US today…California.

    So does it make the case worse or does it create a situation where we get to see the above criteria used. Seems to me that if they are that far gone, they likely wont be back. Anything on that particular part Revere? Has anyone gotten that sick and then made it? Now that would be the bigger question to me. If someone was so sick that they started turning blue or irritable, dizzy can we reasonably assume that this is recoverable with the new flu? Criterias are going to have to be changed and that ethics thing that was discussed about two years ago is likely going to come into play.

    We have about 54,000 beds in the US and thats if we boot the non-criticals out of their beds for flu patients. I would watch this stuff in Oz and read it like a primer for what may come in the early fall. Lets hope it doesnt get worse.

    Revere, if you have anything on single noticeable causes post that up too if you have it.

  10. #10 revere
    June 2, 2009

    Farmer: I agree. I have given her the nod a couple of times (including this post). But it starts at the top.

    Randy: CDC did exactly as required by the IHR and did it better than any other country. It got some push back for recommending closing of schools. It adjusted according to what it was seeing. Not perfect, IMO, but pretty good. We haven’t seen competence like that from a government agency for some time. As for your UHC comments . . . yawn.

  11. #11 stillarebel
    June 2, 2009

    Thanks for the brief descriptions. We have several seriously ill people in Scotland and it appears to be due to community spread, so it is good to know what symptoms to be concerned about.
    Unfortunately the diagnostic criteria in use is still too narrow and the Health Minister seems to be suffering a little from much initial over-use of the word “mild”.
    Personally I think it is very widespread, but that is just my subjective impression from number of people I know with symptoms who are not being considered as potential cases because they have not travelled to known hot-spots or had contact with known cases.

  12. #12 Grace RN
    June 2, 2009

    Well, I suspect my sister has the flu; nausea, diarrhea, severe joint pains, aches, headache, feeling quite lousy but no fever. So feeling quite indispensible, she heads in to work Monday and today, but was started on Tamiflu and steroids for a rash at a minute-clinic. No amount of ‘what about the possible risk to your coworkers?’ will change her mind.

    I’m not holding my breath for NPI’s to work well….

  13. #13 Jan
    June 3, 2009

    This is great info, that should be brought more to the forefront!

  14. #14 Mdaniel
    June 3, 2009

    This is a major problem, but my experience is that many healthcare employers are still enforcing sick leave policies that penalize their employees who stay home when sick. As longas the CDC keeps saying that h1N1 is just like seasonal flu, employers will not modify these and other policies.