Description
Swine flu affects pigs and usually does not infect humans. This particular strain is a new one and contains genetic material from the avian flu virus as well as human inflenza. This newness presents a problem since the more unique a virus is, the less humans have been exposed to it in the past and the longer it takes to mount an effective immune response. For example, a significant outbreak of Hong Kong type A flu (designated by protein type H3N2) occurred in 1968, and I will never forget how ill it made me; however, that past infection will give me protection from future H3N2 flu appearances.
Bird or avian flu is H5N1, and this new swine flu is H1N1. The H and N are designations for specific proteins that are on the surface of the virus:
Symptoms
Many people call usual upper respiratory infections ("colds") the flu, although that is incorrect. Influenza is very different from the sniffles, mainly in how systemic symptoms predominate (fever, headache and muscle aches). It is said that this strain appears to have more gastrointestinal symptoms (vomiting and diarrhea) than the usual flu. Swine flu has a short incubation period (2-4 days) and an affected individual's contagious state will continue for several days even after the peak symptoms are over.
In Mexico, the most severely affected were people between 25 and 45 years of age, and this likely signifies that this age cohort has not been exposed to viruses that carry portions of the protein antigens that this particular virus contains. However, all of us are vulnerable.
It is also interesting to note that the 20 or so individuals affected in this country so far have manifested milder symptoms than the Mexican cases, but this is a small sample so far and things could change rapidly.
Finally, the flu shot you got this year is likely of no help at all with this strain.
What To Do
First: obtain prescriptions for either Relenza or Tamiflu so that you will have it and avoid the rush in case things get worse. Relenza is administered by inhalation (not recommended for asthmatics or those with other types of chronic lung disease) and Tamiflu is a pill. Both are administered twice a day for five days as therapy.
In areas where cases have been reported, wearing a painter's or surgeon's mask should be considered if attending an event with crowds. Wash hands after contact with people, and don't kiss hello or goodbye. If you're ill with possible flu, stay home (another good reason for filling the scrips now).
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Posts
Barry,
ReplyDeleteI'm glad you've posted this. To my knowledge, there have not been any media recommendations about taking any flu shots. I have a question: if the current flu shots won't likely be protective, what would be the benefit of filling a prescription for Relenza or Tamiflu? Do they have broader coverage than the usual standing-order flu shots?
I've never taken a flu or pneumonia shot in my life--they kind of give me the heebie-jeebies, even though I took a slew of them as a kid. It's interesting that I am now developing content for a pneumonia vaccine and am considering getting one for the first time in my life.
I'd really like to know your perspective.
~Jacqui
Jacqui:
ReplyDeleteFlu shots initiate an immune response against the protein parts of the virus; they allow your body to "be ready" for a flu virus with protein components related to the ones in the flu shot that was given.
This virus has proteins that are different than the ones in the flu shot given this season so they are essentially worthless for this edition of the swine flu.
Relenza and Tamiflu are drugs that interfere with the influenza virus' ability to live and reproduce. Totally different mode of action.
Great post Barry,
ReplyDeleteIs there anything you can do to protect small children? Tripp is only 2 years old so I wonder if there is something we should be doing for him.
-Patrick
Flavia said
ReplyDeleteBarry,
thank you for posting this
I found quite surprising that it is happening for the first time since we had pigs around for awhile....As a matter of fact, I have seen that a swine flu vaccine was designed before. Do you know??
Indeed what's really matter are the antigens and the fact they are "new".
I am sure they are starting today to prepare a swine flu vaccine..........
I was wondering, being a mother, any flu is "new" for my baby's immune system, so any flu carring moderate symptoms should have the same risks, swine or not, correct?
also, does the fact it is spring and we go outdoor more make the spreading less likely to generate an epidemic/pandemic? also less likely a coinfection with the standard flu and some recombinant "monster" to appear??