nos-trum. pronunciation: \nos'-trum\. noun. Etymology: Latin, neuter of noster our, ours.
1. a medicine of secret composition recommended by its preparer but usually without scientific proof of its effectiveness.
2. a usually questionable remedy or scheme.
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Thursday, April 30, 2009

SWINE...WOOPS..I MEAN H1N1 INFLUENZA

Newsletter recipients:  I’m going to keep up a running dialogue on this outbreak for a while.  If you want to op-out, let me know.  I’ll get back to the regular-type issue later.  There’s some interesting medical research that’s been piling up in my notes.

 

Back to the flu:

The interesting thing about the data today (below) is that California has not really changed, Texas increased by 10, but New York didn’t accelerate from their initial quick increase—in fact, Calif dropped by one case, from 51 to 50…as did Michigan.  Possibly due to some false positives.

 

Containment is very difficult for a disease that has high infectivity and rapid transmission.  Influenza is one of those diseases.  Nature note:  The all time champ for quick and sure spread is chickenpox.  Some of you may remember being sent to a neighbor’s house to play with their kid who had the disease, so that you would get it…and get it over with.   It only took a couple of hours in the same room.   Chickenpox was seen as a fairly harmless disease.  Only later in medical school did I learn there were things like chickenpox pneumonia, and chickenpox encephalitis—thankfully both are rare in developed countries.  Whew….

 

There’s still not enough data to say whether the point outbreaks will accelerate, begin a new round of cases, or remain fairly stable.  If an index case has exposed a new group of people, you will see a new locus of disease pop up over the next couple of days.  The case pattern in Texas, while not large in numbers, is broadening:  yesterday we had Seguin, and Richardson.  Reports of cases in a couple of new places need confirmation.  I’m cautious about this because there have already been maliciously false rumors of spread.  One rumor of a case in an adjacent county was debunked by the news media.

 

Clinical severity is turning out to be moderate in most cases (so far).  One death (and that one a small child) out of a hundred is not unusual for many strains.  The 1918 pandemic was very different:  people were well one day and then dead in as little as 48 hours, with a fatality rate considerably higher.  Since that time the human “herd” has seen H1N1 several times and this has the effect of mitigating virulence.  This is a common occurrence in extended host-parasite relationships:  over time each species begins to accommodate to the other to some extent.  You may ask why the disease appears much more severe in Mexico:  this is pretty standard.  Indigenous populations in developing areas always do much worse. 

 

For those of you who may worry that you wasted your time getting the flu shot last year…don’t.  There’s some evidence to suggest that having annual vaccination, even with a different strain, imparts a “touch” of immunity that is broad-based.  Not enough to keep you from getting the disease, but maybe to make it a little less severe.  So get that flu shot every year.

 

The president’s call for more spending on influenza research is mostly pointless, but well-intended, providing reassurance that the government is responding.  There is a vaccine in early trials right now that might solve the problem of needing an annual shot to account for changing patterns of the virus.  A lot of money is already spent every year on influenza research.

 

Doc D

 

 

 

U.S. Human Cases of H1N1 Flu Infection
(As of April 30, 2009, 10:30 AM ET)

States

# of laboratory confirmed cases

Deaths

Arizona

1

 

California

14

 

Indiana

1

 

Kansas

2

 

Massachusetts

2

 

Michigan

1

 

Nevada

1

 

New York

50

 

Ohio

1

 

South Carolina

10

 

Texas

26

1

TOTAL COUNTS

109 cases

1 death

 

 

 

 

Wednesday, April 29, 2009

HOG FARMERS WANT US TO STOP CALLING IT "SWINE" FLU

Here’s the update from the CDC as of 40 minutes ago.  You can see that New York is still a problem, but Texas has jumped in numbers, and is reporting the first death (a 2 yr old returning from Mexico, who succumbed in a Houston hospital).  Cases in Texas have also popped up around Dallas, in addition to the Seguin area reported yesterday.  It is suspected that most of the Texas cases are related to travel to Mexico, but this is still under investigation.  Local schools around Seguin have closed.

 

We need to put this death in perspective.  It’s not an indicator of the severity of this illness…yet.   Small children are at increased risk of severe disease in all influenza outbreaks.  In California, there was a 45 year old female who needed intensive care before recovering.  

 

Not listed here is suspected cases in North Carolina.

 

There is one suspected case in New Zealand.

 

Note:  you don’t get swine flu by eating pork.  There are reports of people avoiding pork, and slaughtering hogs.  This is the kind of herd panic we see with human populations.

 

 

 

U.S. Human Cases of Swine Flu Infection
(As of April 29, 2009, 11:00 AM ET)

States

# of laboratory confirmed cases

Deaths

Arizona

1

 

California

14

 

Indiana

1

 

Kansas

2

 

Massachusetts

2

 

Michigan

2

 

Nevada

1

 

New York City

51

 

Ohio

1

 

Texas

16

1

TOTAL COUNTS

91 cases

1 death

 

 

Wash your hands,

 

Doc D

 

 

Tuesday, April 28, 2009

THE SWINE FLU: BROUHAHA OR THREAT?

This is for those who are watching the swine flu saga on television.

 

As of 11 AM Eastern today there have been 64 cases.  No deaths (a little early to tell in many of the current cases).  The points of outbreak are evolving.  Initially there were a handful of cases in California, and two cases in Texas (both states in proximity to Mexico).  Over the last week, there have been no new cases in Texas, but 45 cases have appeared in New York, with 1-2 in Kansas and Ohio.  This is WWAAY too early to tell where this is going.  So here are some useful facts to keep in mind.

 

  1. In a typical year with very low levels of influenza (1-2 million cases), there will be 20,000 deaths.  This is routine and isn’t a marketable media story.  In a “bad” year, there will be 2-3 times this many deaths.  Bad years come from a slightly different strain than what was expected, and therefore the shot doesn’t match exactly, OR people start getting lax about getting the shot and more people are vulnerable.
  2. We’ve had 12 cases of swine flu in this country (total) in the last several years.  There was one death over this period.
  3. The great pandemic of 1918 killed somewhere between 20 and 60 million people world-wide.  This was a H1N1 virus (more on this below).
  4. The terms “swine” flu and “bird” flu come from the source of the new strain of virus.  Hogs get flu every year (as do birds and others)…it just doesn’t jump to humans very often.  Occasionally a random mutation occurs that opens a window to other species, and the virus then propagates though that new host…in this case, humans.

 

There’s no shot for this new strain, because there’s no way to anticipate a random mutation.  There are some drugs that can lessen the severity of (but not cure) the disease when you get sick.

 

90% of what people call the “flu” is not influenza.  It’s cold viruses, sore throat viruses, bronchitis, pneumonia, and a hundred other respiratory diseases.  So just because you get “flu-like” symptoms doesn’t mean you have influenza.  As doctors, we often just put “FLS” under diagnosis, which stands for flu-like syndrome, because there’s no way to distinguish among all the different viruses without doing thousands of dollars worth of tests in a specialty lab. 

 

BUT, there are some symptoms that increase the likelihood of influenza:

 

  1. SUDDEN onset.  Anything that takes several days to crank up is not influenza. (scratch throat first day, runny nose the second, cough the third…not influenza)
  2. SEVERE HEADACHE (co-incident with the onset).  This is not like a sinus headache, or a tension headache, or any of the common head pains we all get.  It’s clearly not there one minute and there the next…and it’s really uncomfortable.
  3. FEVER.  By this, I mean something over 101 at least, and preferably 102-104.  Anything less is trivial.
  4. PAINFUL COUGH.  This cough hurts…in your chest.  This is not a post-nasal drip cough.

 

As you can see, the classic case knocks you flat.

 

Not everybody gets the whole menu, and some people have other symptoms in addition…but these are the signature ones.

 

Prevention:

I don’t recommend meds—there are side effects—unless you are (1) in close contact with someone who’s sick, and (2) you have another medical problem that puts you at risk.  Herbals don’t do squat.

 

  1. Avoid close contact with anyone who has a respiratory febrile illness.  “Close contact” means “within six feet.”
  2. Wash your hands frequently…and I mean really wash them:  15 seconds (one potato, two potato…).  It’s not the soap that’s doing the job, it’s the mechanical scrubbing.

 

Transmission of viral illness by contact is under-recognized.  There’s some evidence that direct contact causes more illness than aerosol spread.  So, scrub away, all day long.

 

You can use the hand sanitizers, but they are not as effective as hand washing. 

 

The classification scheme:

 

--There are three types of influenza virus:  A, B, and C

 

A causes the most severe disease in humans, and all the HN sub-types are in this group.

 

B has one species, specific to humans, but it’s less severe and we all carry some partial immunity to it for longer periods of time.

 

C has one species, humans are the only host (except seals, for some reason).  It’s less common and causes mild disease.

 

 

--Under the “A” type, the strains are named by referring to two enzymes coded by the virus:  Hemaglutinin and Neuraminidase, hence H and N.  They are just markers.  So there’s:

H1N1, which caused Spanish flu in 1918 and is the sub-type we are dealing with now, H2N2, which caused Asian Flu in 1957, H3N2, which caused Hong Kong Flu in 1968, H5N1, the avian flu we all got worried about in 2007, H7N7, H1N2, H9N2, H7N2, H7N3, H10N7…

Confusing, isn’t it?

Lastly, watch the pattern of spread.  I’m not sure if this one’s going to peter out or really get rolling—SARS looked like a good bet to accelerate, but reached a peak quickly.  It’s unusual in a number of respects, not the least of which is that it’s almost summer, well past the usual season.  Another interesting feature is the quick growth of cases in New York:  I’m told there was an index case from Mexico that arrived through the airport.  Throughout history this is how plague, cholera, and their ilk have jumped from one city or continent to the next.

Doc D

 

 

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