Tuesday, April 28, 2009

Swine Flu updates from CDC...

Below is a CDC website where you can track the swine influenza situation in the United States:

CDC Swine Flu Website

Also, the U.S. Department of Health & Human Services has a webpage for information related to pandemic flu... with FAQs related to seasonal flu, swine flu, avian flu and more:

U.S. Department of Health & Human Services Pandemic Flu Website

Finally, here is a link to basic information about the influenza viruses that typically cause the seasonal flu:

CDC Seasonal Flu Virus Website

~~~~~ BIO26 ~~~~

Thursday, April 23, 2009

You got the Swine Flu?

Almost everybody has heard of the ominous bird flu or avian flu. But new on the horizon seems to be swine flu. Just like humans, birds and pigs get the flu... influenza viruses which cause respiratory illness. Not commonly, but from time to time these strains of avian or swine influenza are transmitted to humans... usually people in close contact with birds or pigs. Interestingly, several cases of a new strain of swine/pig influenza (which is different from human influenza virus) have been identified in people without known contact with pigs. It also appears that this swine influenza strain might be spreading from human to human contact. Whereas some strains of avian influenza are very deadly in people, this swine influenza virus has not been reported to cause severe illness as of yet. Check out the link to the Centers for Disease Control report on two of these swine flu cases... it is pretty interesting (link here). I have included a couple short excerpts from the CDC's website:

"The lack of known exposure to pigs in the two cases described in this report increases the possibility that human-to-human transmission of this new influenza virus has occurred." "Because these viruses carry a unique combination of genes, no information currently is available regarding the efficiency of transmission in swine or in humans. Investigations to understand transmission of this virus are ongoing."

"... concern exists that this new strain of swine influenza A (H1N1) is substantially different from human influenza A (H1N1) viruses, that a large proportion of the population might be susceptible to infection, and that the seasonal influenza vaccine H1N1 strain might not provide protection."

~~~ BIO26 ~~~

Friday, April 17, 2009

Unrecognized (Silent) Non-Q-Wave Myocardial Infarction...

Just being able to say that will make you sound real smart with your friends and co-workers. You remember that myocardial infarction (MI) refers to death of the heart muscle due to interrupted or impaired blood flow to the myocardium. What about Q-waves? Recall the ECG, with the P-wave, QRS complex, and T wave... the Q portion of the QRS is normally a very small downward blip just prior to the large, prominent R peak. Anyway, large and evident Q waves are used to detect a previous MI. Other ECG abnormalities (ST changes) can suggest an acute MI or MI that is currently happening. These Q waves though show old infarctions. Believe it or not, some patients have an MI and never even notice it and may not report problems to their doctors. This is considered a "silent" or unrecognized MI... later these silent myocardial infarctions can become evident as large Q waves in the ECG. Okay, okay, we are getting to the unrecognized Non-Q-Wave Myocardial Infarction part. So consider if your patient has had one of these silent MI's BUT say they don't ever develop the abnormally large Q waves? How would you know they had a silent heart attack? You wouldn't know, right? Well, some clever scientists recently reported their use of MRI's to detect these "Unrecognized Non-Q-Wave Myocardial Infarctions." You should be feeling pretty smart by now. What is the importance of all this? As posted at PLoS Medicine, here are some possible implications of this study (summary link; article link):

  • Silent or unrecognized MI's are not being detected in patients with heart disease, since they don't always have Q waves on their ECG
  • Using MRI to detect these silent MI's showed that 70% of silent MI patients lacked Q waves whereas only 30% of patients with silent MI had Q waves
  • It seems that in silent MI (which are often small) the use of Q waves is going to miss a significant portion of patients with silent MI.
  • Non-Q-wave MI is important because it is significantly associated with increased mortality. So we would want to be able to identify these patients.

~ ~ BIO26 ~ ~