Evolution of the H1N1 Influenza Virus

In 2009, an H1N1 Influenza Flu Pandemic (Swine Flu) caused a global uproar and left thousands of people dead.

Compared to other strains of H1N1, the 2009 Swine Flu was a novel virus (new) and there was no vaccine immediately available.

Although the 2009 pandemic did not cause nearly the same level of death and destruction as past flu pandemics, it was still a major concern.

The 2009 H1N1 strain made a lasting impression on me because it affected my life directly, so I decided to write a short scientific summary of the evolution of the virus, and share my personal story as well.

Meet Influenza A Virus Subtype H1N1
Meet Influenza A Virus Subtype H1N1

Basic Introduction to Influenza

Influenza, or the flu, is an acute, highly communicable infection that causes respiratory illness.

The virus is a serious health threat, capable of causing yearly epidemics.

Most healthy individuals recover from the flu, but the virus is still responsible for approximately 36,000 annual deaths in the United States.

There are three types of influenza: A, B, and C.

Influenza types A and B are the chief culprits of seasonal flu outbreaks across the globe.

Influenza type A is the most prevalent and noxious type of the virus and it attacks humans and animals.

Influenza is hard to eradicate because it constantly changes and adapts.

Reassortment & the Emergence of a New and Deadly Strain

Influenza type A has three different subtypes that affect humans, they are known as H1N1, H1N2, and H3N2.

A new strain of Influenza A Subtype H1N1 is responsible for the 2009 Swine Flu Pandemic.

The Centers for Disease Control (CDC) has concluded that the new strain is the result of a biological process known as reassortment.

Reassortment occurs when an animal host becomes infected with multiple influenza viruses.

In this unique condition, the viruses swap genetic material and produce a new strain that carries a genetic combination of both “parent” viruses.

Why is it called the Swine Flu?

The bodies of swine offer the perfect environment for the reassortment process because they have the ability to contract both forms of the flu (swine & human).

Why is it called the Swine Flu?
Why is it called the Swine Flu?

The reassortment process is suspected to have occurred in North American and Eurasian pigs. Traditionally, the H1N1 strain that affects pigs is unrelated to the one that affects humans; however, a major change (antigenic shift) in the virus caused it to have properties owning the ability to attack a human host.

Reason Why the Typical Flu Vaccine Did Not Work

Because the resulting virus is a novel infection (new and unfamiliar), human antibodies have no means of identifying and neutralizing it. This novelty is the reason why traditional flu vaccines had absolutely no effect on the 2009 H1N1 viral strain.

Key Concepts

  • The virus can be considered to be novel because it had never infected humans before, or it isn't infected humans in a considerably long amount of time. When such a situation occurs, usually no one is immunologically prepared to fend off the virus. However, reports indicate that people ages 65 and older likely have some sort of immunity to this particular strain of flu.
  • According to the Centers for Disease Control (CDC), the 2009 form of H1N1 probably naturally evolved over a long period of time, circulating in an unidentified animal host, and remaining hidden from discovery until it caused the pandemic of 2009.
  • Through the process of antigenic shift, the 2009 H1N1 Swine Flu is changed on a cellular level which affects the process of protein synthesis. This is basically the major change that has morphed the disease and made it different from other forms of influenza.

We Knew Something Was Wrong When This Little Rambunctious Mini-Terror Was Listless for an Entire Day (My Grandson Christian)
We Knew Something Was Wrong When This Little Rambunctious Mini-Terror Was Listless for an Entire Day (My Grandson Christian)

How I was Personally Affected by the 2009 Swine Flu Pandemic

MY GRANDSON becomes INFECTED with H1N1

My grandson, Christian, became very ill in 2009. It all began one day when his mom noticed that he was lethargic for most of the day (which was highly unusual, because he is a rambunctious child).

He had a runny nose and sore throat, so we initially passed it off as a common cold.

Later that evening, he developed an exceedingly high temperature, so we took him to the emergency room in the middle of the night.

It was there that we learned that he had somehow contracted the swine flu. He was given a prescription for an antiviral called Tamiflu, and we were sent home and told not to worry about spiking fevers.

I BECAME INFECTED with H1N1

Less than a full day later, I began to experience some of the same symptoms. I went to my personal physician and I was given Tamiflu as well.

My daughter did not get sick, so she took care of me and Christian for about 3 days. The two of us laid around in our "sickroom" for most of the day.

It was frightening for me because he was extremely listless and pale and often subject to bouts of projectile vomiting.

Eventually, the two of us got over the disease and things returned to normal.

A FAMILY FRIEND becomes INFECTED with H1N1 & is GRAVELY ILL

About a week later, we heard that a long time family friend had become infected with the Swine Flu as well.

Because me and my grandson had already weathered the disease, I figured that she would eventually pull through as well.

But then, we heard that she had been hospitalized. It was a bit of an alarm, but I still had high hopes that she would recover.

I was wrong. She never recovered. Because she had pre-existing medical conditions, her body was unable to fend of the attack from H1N1, and so she died in the hospital... completely surrounded by competent medical professionals who could not save her from the flu.

The 2009 Swine Flu pandemic took the lives of more than 18,000 people worldwide.

Indeed, it did not have the same devastating effects of the Spanish Flu Pandemic which claimed the lives of more than 50 million people in a two year period (1918 - 1920).

However, all it takes is one single microbe to infect at least one person you know. . . and you will think begin to think very seriously about the realistic threat of influenza.

Get Vaccinated, and keep a watchful eye over the sick, young, and elderly people in your life when a flu outbreak occurs, because they are the most susceptible to infection.

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Comments 1 comment

RTalloni profile image

RTalloni 5 years ago from the short journey

So sorry for your loss.

Am glad to see a heads up about the flu--nothing like a personal account to help us think twice. Careful hand washing would take us a long way with this and other bugs, but so few cooperate!

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