About the flu

9 08 2009

swineflu virus2

What is influenza?

There are three kinds of influenza virusses:
-type A usually the cause for outbreaks
-type B, linked to sporadic cases
-type C, rarely causes disease response

The Flu is a respiratory infection, connected with a fever, coughing, and muscle aches, which often lasts a few days. It affects about 20% of the world’s population. While the disease itself is usually harmless, it can carry a risk of viral or bacterial pneumonia, which can prove fatal, especially for the very young, elderly, or those in poor health. Centers for Disease Control and Prevention based in Atlanta, Georgia estimates that during the 1990s, about 36,000 people died each year of flu-related causes in the United States.
For comparison, the bird flu outbreak between 2007 and 2009 claimed about 100 deaths in total.

N’s and H’s

The surface membrane of the virus is spiked with two types of protein molecules: hemagglutinin (marked with letter “H“) and neuraminidase (marked with letter “N“).
Hemagglutinin molecules are used to bind the virus to a cell and inject its contents into it. Neuraminidase is a special enzyme which is required for viral infectivity and used to break the infected cell in order to release new viruses, which can spread infecting other cells.

The infuenza virus can change these N and H molecules, which is called antigenic shift.

For example, the swine flu which appeared in 1918 was named H1N1, while a later strain of influenza which was found to have changed its hemagglutinin molecules was named H2N1, and an even later influenza was found to have changed both its surface molecules (double antigenic shift), and was named H2N2. These changes are the result of an exchange of genetic materials between flu viruses originating from different sources. For instance, if a flu virus from a swine was mixed with a human flu virus, this could create a new strain that has swine-type hemagglutinin (H) and human-type neuraminidase (N). At this time there are four main Influenza A swine flu virus subtypes: H1N1, H1N2, H3N2 and H3 N1. However, the most recently isolated viruses from pigs have been of H1N1 subtype which was the cause of the original 1918 pandemic. The new flu strain is a combination of pig, bird and human viruses to which humans may have no natural immunity.

There are also frequent point mutations in the viral RNA and other changes that make up such a variety of flu strains. Such variations in the genetic composition of viruses usually occur after the population has built up immunities to the old strain.

This constant shifting of molecules and mutation in RNA, is the reason why a flu-vaccin usually doesn’t work the next year: the flu has mutated into another flu by that time. Which is also why you keep getting it: any flu which you have survived you are immune to, but the next time the flu comes around it probably has changed and so you get it again 😦

So what happens?

Viruses enter the respiratory tract and bind to the cells lining the lung airways. After entering the cell, the viruses use their genetic material, which is in the form of RNA, to transform the cellular machinery of the host cell to set up the production of new copies of viral genes. These genes combine with new viral proteins created in the host cell and then bud out of the cell as fresh viruses.

These newly produced viruses spread out causing infection of neighboring cells of the lung tissue. In order to spread they produce enzymes that destroy collagen and other components of the connective tissue surrounding all cells.

Fight influenza!

Inhibition of these enzymes, which is possible with the use of vitamin C, Lysine and other components of “nutrient synergy,” is very important for curtailing the spread of any viral infection in the body.

Currently there are two classes of drugs approved for the treatment and prevention of flu: the adamantanes (Amantadine and its derivative Rimantadine) and the newer neuraminidase (NA) inhibitors such as Oseltamivir and Zanamivir. Adamantanes interfere with viral processing inside a cell and are associated with severe toxic side effects and development of drug resistance. The most recent swine flu viruses isolated from humans are resistant to Adamantine and Rimantadine.

Neuramindase inhibitors are aimed at blocking the enzymatic function of neuraminidase thereby preventing release of the viruses from infected host cells. Neuraminidase inhibitors must be administered very early since the replication of influenza virus in the respiratory track reaches its peak after 24-72 hours after infection. However, the benefits of their use are not so evident. For instance Tamiflu (oseltamivir) may reduce illness by only 1-2 days, but at the same time it poses a risk of developing side effects such as nausea, vomiting, and abdominal pain in about 5% of patients. See previous post. Also, Tamiflu does not prevent or cure the flu – it can only slightly reduce its length or severity of symptoms.
Recent reports of its use in Japan, where Tamiflu prescriptions are ten times higher than in the US, reported bizarre psychiatric problems in children, even leading to death. More recently, the US FDA has recommended a new warning about possible dangerous psychiatric side effects of Tamiflu and Relenza. During the last winter flu season of 2007-2008, about 11% of flu cases were reported to be resistant to Tamiflu, with substantially higher incidence of resistance reported this fall for the most common circulating viral strain causing the flu.

Unfortunately, because of their synthetic nature it is difficult to find a drug which interferes with the biological processes of the virus and which does not also hurt the cell. This is why drugs always carry a risk of side effects, especially in immune challenged patients, particularly the very young, and the elderly suffering from other diseases and taking multiple medications at once.

Antibiotics, do not affect the flu or viral infections. They are often prescribed against secondary bacterial infections. Unnecessary use of antibiotics leads to the development of bacterial resistance, rendering them ineffective against many types of infections.

Vaccines, which trigger the body’s production of antibodies without actually causing the disease, are usually more productive, however, due to frequent genetic changes in the flu virus they are often ineffective for this problem.

Humans cannot produce vitamin C in their own bodies, vitamin C has been proven in many studies to inhibit the spread of virusses. You will need to take the vitamin in far larger doses as is usual in commercial vitamin pills.

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8 responses

9 08 2009
sabiwabi

This was a great post. I still don’t think most people understand the importance of supplements and vitamins and the impact they can have on their health. Since I started giving immune boosting supplements to my children, the difference has been amazing. Also my 2 year old nephew (who has always been given great supplements) actually kissed his Aunt on the lips on the very day that she came down with swine flu….and he caught nothing, thank God.

12 08 2009
Aafke

Sabiwabi, that’s great! And good for your little nephew!
It’s also very important to keep your hand clean, you can give your children (if they’re old enough) a little bottle of disinfectant gel, and tell the to rub their hands with is now and then, until the flu has passed.

13 08 2009
intlxpatr

Aafke, I wondered where you were, and with my own recent move and lots and lots of guests coming through, I hadn’t taken the time to look in on you.

Blogging is a risk, you are right.

And you can blog anyway – no one really knows what you are leaving out. I admit, I have been hooked on a lot of the Arabic-inspired posts, mostly because you did such good research, but I honor your decision to limit your posts.

13 08 2009
Aafke

Ah, intxpatr, I also am rethinking my priorities, at the moment I really want to focus more on my art.
I have been reading up on your moving-peccadillos but I also have a lot less time for commenting 🙂

14 08 2009
intlxpatr

i’ve been thinking about your post about re-thinking, and the one thing, given the scope of your blog, that I wouldn’t worry about is the blurkers. Most people don’t comment who visit – a few will, those sort of in tune with what you are saying or those borderline personalities who want to draw attention to themselves and who can get ugly. But the 99,9% who show up are usually just dropping by. I know I get lots and lots of visitors who have googled something and it leads them to my blog, and then they don’t get what they need and move on. I don’t worry about it.

I have a program called StatCounter. It is a great little program – free – that allows you to see who your visitors are and where they are coming from. Some, you can lable because you know their IP’s from their comments on your blog. Some, you can see, come just for a second or two – they are looking for something, and because your blog has a huge and varied content, you will get a lot of those, people who come and go because you don’t have what they are looking for.

Larger content, larger vocabulary = greater chance of getting hits

🙂

14 08 2009
Aafke

I know! I get hits on ”nudity” ”abaya” and weirdest of all: ”Hairy women”!!!
And when I was so unwise last week to place a cute photo labelled ”kittens” I got three hundred clicks per day on that one alone!
I had to take it off, delete it, and rename the photo ”web 3” or something before I put it on! And the kitten tsunami has finally abated!
but I also get about 130 clicks straight on the Religions, women and dress post, and no referrer.
I have statcounter but I can’t find out where they are coming from.
never mind, I truly want to get to do more art, and get my art-site up and running!

15 08 2009
Intlxpatr

Sounds like a worthy goal. Will you let me know when it’s up? 🙂

18 08 2009
Aafke

Yes of course! Working on it right now!

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