Examining Influenza

Wolffman writes "University of Wisconsin-Madison scientists have solved a long-standing puzzle about how the influenza virus assembles its genetic contents into infectious particles that enable the virus to spread from cell to cell, scientists have opened a new gateway to a better understanding of one of the world's most virulent diseases."

Comments

Kawaoka

[GrimSean]

Yoshi Kawaoka who is the principle person behind this research, also works with Ebola. I would be interested to know if the Ebola virus uses a similar method of infecting host cells, as I believe both it and the Influenza A virus have a similar incubation period.

The article states that a single RNA strand is responsible for recruiting the other seven, which then work together to produce more virons. I'm curious as to whether it is that RNA strand which has to mutate in order for the virus to jump from species to species (such as from birds to humans). Perhaps this could lead to a new innoculation for birds that would prevent their viral infections from jumping ship to us.

Re:Kawaoka

[Simon Field]

The article says "What's unique about this virus is that its genome is fragmented into eight RNA segments".

I assume that if this makes it unique, then ebola probably doesn't share the trait.

Immunizing wild waterfowl in southeast asia would probably require something like a genetically modified bacteria that expressed the same antigens as the virus, triggering immunity. Such a bacterium could be introduced into their habitat.

However, since pigs are the intermediary link, it would probably be much easier to innoculate pigs at the same time you innoculate humans. Then you could use a normal vaccine. But first you have to make a vaccine that targets some highly preserved section of the viral DNA, since the protein coat mutates quickly.

One thing that always worries me

[phorm]

When scientists are attempting cures with diseases at a genetic level, there is always a possibility of creating something worse, or a really nasty mutation. Antibiotics, for example, can make a virus more resistant if they don't kill it the first time around.

Still, I am hopeful - since the more we know about such virii, the better we can combat them. The issue is in knowing enough to develop countermeasures but not enough to predict future consequences.

Re:One thing that always worries me

[Simon Field]

Of course, antibiotics aren't useful against viruses, but presumably any antiviral agent that does not kill the virus effectively will give the virus a better chance at developing resistance.

I am somewhat skeptical (ok, paranoid) about the motives of drug companies. It looks to me like it is in their best interest to develop drugs that turn a fatal disease into a chronic one that needs expensive drugs for life. If they develop drugs that actually cure the disease, they make less money. Where is the most money being spent and made -- on anti-virals, or on vaccines?

How many companies that sell cold remedies are working on vaccines for the common cold?

Re:One thing that always worries me

[Jelanen]

Its important to point out that antibiotics cannot and do not make bacteria resistant. Due to the immense populations that bacteria like to exist in, toss in some regular Mk1 Mod0 life randomness, there is almost a certainty that a percentage of the bacteria that already exist in a population are already resistant to the antibiotic before you even apply it. So, all you do is chop off the part of the population distribution that is susceptible to the antibiotic and the resistant ones get to grow and multiply to fill the space once occupied by antibiotic-susceptible bacteria. I am so sick of so-called medical experts screwing this up in print and TV news. Its one thing to wallow in your own ignorance, its another entirely to pass your disease onto others!

Just a further note though, very few antibiotics actually work on bacteria at a DNA level. Most instead like to hack and slash at a bacteria's cell wall or plasma membrane. Some (my personal favorites) are metabolism arresters that attack metabolic enzymes that the bacteria uses to make energy for life processes.

Re:my question to anyone who can answer it...

[Bowling Moses]

Probably not. I'm not a virologist but it wouldn't necessarily be enough to eradicate the disease among humans only. Some (many?) virii have the ability to infect multiple species, for example the West Nile virus can infect humans, horses, and crows. Also I remember years ago when I was an undergrad looking at a cladogram following the evolutionary phylogeny of the AIDS virus. At that time there were only a couple hundred different virii but they targeted more than one species. Virii mutate, so its possible under odd circumstances that they occasionally jump species, so a related influenza, AIDS, etc. could reinfect us. Little bastards.

Re:my question to anyone who can answer it...

[PeterM from Berkeley]

Well, smallpox was eradicated by immunizing everyone. There have not been any natural cases of smallpox for a long time, and there will be none unless some madman commits a crime against all of humanity by re-releasing that virus.

However, influenza, for example, infects other animals than humans. So does the bubonic plague. Complete eradication of these disease would therefore be very difficult.

Polio can be eradicated, though, and so could some others, because no other hosts than humans exist. We are well on the way to eradicating polio.

Influenza pandemics

[juushin]

The article is interesting, but falls a bit short of describing why this study describing how viruses package themselves and spread is so important (it does briefly mention the influenza pandemic of 1918 which is believed to have killed tens of millions worldwide, thereby illustrating the devastation of influenza).

What the article fails to mention is how strains of influenza can become particularly virulent against humans. Traditionally, as in the 1918 pandemic, this occurs when a strain of swine and avian influenza combine. The likelyhood of this recombination occurring to produce a lethal strain is low (consider that the Spanish Influenza was brought about by a strain of avian influenza believed to originate in China and a swine strain believed to have originated from another area of the world). However, statistics show that this recombination occurs regularly enough to pose a serious risk and that it is only a matter of time...

If one traces outbreaks of influenza worldwide, it becomes clear that every ~20 years, an outbreak occurs due to a recombination of swine and avian viruses that leads to the infection of humans.

Let's hope that scientific strides, such as that made in this recent PNAS article, can be used to nip future viruses in the bud, or be used to make new vaccines.

I had a little bird It's name was enza

I opened the window

And in-flu-enza