Archive for October 28th, 2009
The Virus and the Swine
The Virus and the Swine
Influenza A viruses have segmented, negative-sense RNA genomes that encode up to 11 proteins. These include the surface glycoproteins hemagglutinin and neuraminidase and the virulence factors NS1 (host interferon antagonist)and PB1-F2 (proapoptotic factor). The viruses are grouped according to theexpression of 1 of 16 hemagglutinin subtypes and 1 of 9 neuraminidase subtypes (Palese and Shaw, 2007).
The elusive nature of influenza viruses as targets of adaptive immunity is mostlya function of the hemagglutinin molecule, the major surface antigen eliciting protectiveantibodies. The hemagglutinin is a remarkable structure, accommodatingsignificant morphological changes while maintaining its crucial functions in attachingthe virus to the host cell and mediating fusion of the viral and host membranes.Entry of influenza viruses into cells depends on the presence of a functional hemagglutinin molecule and expression of the host cell receptor for hemagglutinin, sialic acid.
Humans and avian species differ in the expression of sialyltransferases in mucosal and respiratory tissues resulting in N-glycans with either α2,6 (human) or α2,3 (avian) linked sialic acids. The ability of a particular virus to bind to either of these two conformations of terminal sialic acid is thought to be the basis for the host restriction that is characteristic of influenza viruses.
An avian virus that acquires the ability, via mutation or reassortment, to bind to α2,6-linked sialic acids may cross the species barrier and become infectious in humans. Infections in swine are thought to mediate virus reassortment because swine tissues express both forms of sialic acid, enabling cells to be coinfected with avian and human viruses (Olsen, 2002).
Viruses adapted to swine can also combine with human and avian viruses to produce triple reassortants that may have the ability to infect humans. The 2009 H1N1 swine influenza virus is an example of a triple reassortant
Influenza viruses demonstrate variations in their ability to be transmitted between humans. Molecular markers predicting the ability of a virus to be transmitted have not yet been determined. However, low temperature and low humidity are known to be environmental conditions that favor aerosol transmission, explaining the seasonal nature of normal influenza
(Lowen et al.,2007).
This morning I finished watching “The Time Is Now” Season 2 of MillenniuM and got to thinking about the swine, avian, and other pandemics out there that might happen. As we are in the midst of the H1N1 pandemic I thought it appropriate to give it a closer look.
Turns out that the H1N1 is a close relative of the 1918 H1N1 that only lack a couple of protein sectors to make its lethality and transmissibility nastier. Sure, you think “whew we’re good!” but the reality is that these two proteins could easily pop up because of the nature of the swine flu and the nature of the swine themselves that allow for easy re-assortant.
Simply, this bug, because it is from swine, and swine express both the vectors of avian protease areas as well as human.
Thus the likelihood of another shift to allow for these proteins to be installed within the virus is much higher a probability than one might think. It’s just a matter of time really before this happens and really, I think that the avian portion of the picture will re-assert itself and we will see the full effect of a triple reassortant virus.
This week the President declared an emergency, the WHO declared pandemic a while ago, and the press ran away with the ball like chicken little. The populace though, seem to be rather lax about the whole thing because they fail to understand the dangers I think. The following things make you more likely to have real problems should you contract this virus.
- Asthma
- Heart Disease
- Pulmonary diseases
- Immunocompromised individuals
- Obesity
- Pregnancy
Never mind that this virus has been striking people in their teens and 20’s who do not have any of these problems with their health. Because this is a respiratory illness that causes pneumonia, it is more likely to actually kill you than the average flu, and yes, the average flu kills about 200K people a year. H1N1 thus far has killed 246K people. It’s a bit more virulent. And yet, it is not 1918 virulent yet. In 1918 in 25 weeks approximately 25 million died from its effects. Swine flu is it’s tamer but mutation friendly cousin.
And you wonder why officials get spooked about this one?
So, yeah, I am kinda worried about this bug. I have the asthma and have to wonder about getting the shot or nasal swab to hopefully prevent getting sick. I also have to wonder about the CDC’s page that says that CT has “widespread” cases of Swine. Not pockets, its just all the hell over the place. Of course people are not dropping dead of it as I have heard… But, I don’t want to be in ICU with acute respiratory issues because I got it and have asthma. That would be bad. Guess I will have to talk to the doctor.
This all got me thinking though about BW and just what’s been going on since our last episode with the Anthrax that was sent to Tom Delay and others. Which, whatever happened to that case huh? Is it closed now because that guy committed suicide after they hounded him? Last I had heard there was no concrete evidence that he had in fact manufactured the Anthrax to the BW level and sent it. This got me thinking though about the old Sov program in BW.
I took a stroll though Google and came up with an interesting story back in 2004 by the CBC on Biopreparat and VEKTOR. Evidently even in 04 there was monkey business going on in the old Sov state. They had allegedly moved their BW programs to the military area and went completely black. To give you perspective, the defection of two high ranking doctors back in the late 80’s pretty much put a crimp in the Sov’s bioweapons programs… But, evidently not enough of one to stop them.
Nope, they have kept on making new and improved weapons. In fact, they came out back in 2001 with a report that they had “accidentally” created a vaccine resistant strain of anthrax. A strain they refused to give any data or samples about when asked by the rest of the world to assure that it was indeed resistant to not only the Sov vaccine, but also the US and others.
They just said nyet. So who knows what they have now.
But Putin is our friend! W looked into his soul!
Right.
Oh well, I have dug up a bunch of docs for you to peruse. I guess the real thing for me here:
What’s your labile swine flu pandemic plan?