Today our life are attacked by many crisis’s and problems whether relationship, studying, financing etc. Unseen enemies who defeat us from the outside as well as inside like disease and illness. For a decade, the medical sciences have been explicitly developed. Serious diseases were cured and saved many lives. Surprisingly, no matter how advance we would be we have never been conquered a single celled creature like pathogen. Isn't it possible that while we, human being, are evolving, the pathogen also is.

         While I was writing this column, the word of " new H1N1 swine flu" was buzzing from colleagues, television or other press and the bounce from people' re-action were weak as just acknowledge the information to strong like scare of eating pork. Influenza or what we call 'flu' is an infection disease cause by RNA viruses that affects birds and mammals; it spreads around the world in seasonal epidemics, resulting in the deaths of hundreds of thousands annually - millions in pandemic years. Thailand also has a risk with 10 different kind of epidemics besides the 'new H1N1 swine flu'; Avian influenza, SARS, Japanese B enephalitis, Nipah Virus, Hanta Virus, Menincoccal disease, hand, foot and mouth disease, Brucellosis, Leishmania, E.coli 5017.

        Technically there is flu pandemic every year. But the term is usually reserved for bad outbreaks that follow large change in the virus. When the virus which constantly evolves gets new surface proteins that people have little immunity to, generally because they come from an animal strain. The lack of immunity means the virus affects more people more severely. That's why H5N1 bird flu is so dangerous as the H5 surface protein is totally new to humans, and the virus has killed more than half of the people its infected. Another bird flu that can infect human is virus from the H7 or H9 families, so we need to be ready and aware that it might become pandemic.

        The H1N1 type of flu has been circulated once in 1976 so it's less receive attention however the Mexican strains having different type of H1 so it cause some trouble for us but merely be pandemic unless it could find a way to transmit from one to another a lot faster.

The mutation of pathogen

        Millions years ago, the dinosaurs were living on the earth but many scientist are assume that the extinct of dinosaur might come from the time that climate rapidly change. The dramatic change was too much for them and cause them were not able to survive. To live on is what we, whether human being, animal or any creatures on earth are fighting for even small creatures which call pathogen.

        I don't think the pathogen is able to think but its nature has made them find a way to survive. The changing of the virus genome happens in two ways:

        Antigenic shift - when two viruses infect the same cell at the same time, they could exchange RNA segments, making a new type of virus. For example the virus H7N2 and H3N1 can cause a mutation virus H7N1.

         Antigenic drift - normally virus RNA naturally mutates over time. And the altered structure can cause changes like infectious ability

There are three main hypotheses about why a pathogen evolves as it does.

1.Trade off Hypothesis - there was a time that some biologist argued that pathogens would tend to evolve toward ever decreasing virulence to allow the host  to move around and interact with other host so the pathogen can transmit itself to a new host.

2. Short-Sighted Evolution Hypothesis - the evolution of pathogens is occurred due to increase reproduction rate and transmission to a new host more efficiency so the ability to reproduce sooner, faster and higher number, live longer , survive against antibodies.

3. Coincidental Evolution Hypothesis - the virulence of many pathogens in human may not be of selection itself but rather an accidental by product of selection that operate on other traits. Like the new Swine Flu though about 200 pigs from a herd of more than 2,000 developed symptoms, but none have died. The mutation of H1N1 virus might happen when it transmits between humans and pigs and increase its virulence.

The strength from inside out
    Any pathogen would infect and cause the symptoms to the same group of people; weak body and lower antibodies especially children and elders. As Charles Darwin's theory has stated that " As many more individuals of each species are born than can possibly survive; and as, consequently, there is a frequently recurring struggle for existence, it follows that any being, if it vary however slightly in any manner profitable to itself, under the complex and sometimes varying conditions of life, will have a better chance of surviving, and thus be naturally selected. From the strong principle of inheritance, any selected variety will tend to propagate its new and modified form"
    If we look back to the history, pandemics or disasters were the naturally selected procedures. The survivors were strong and capable to adjust themselves to live on. Personally, I think human being is evolving through technology and by that they become weaker. We created the mechanic machine to help us work faster, dam to store water for out of season agriculture, house to keep us warm in the winter and cool in the summer, Penicillin which are Beta-lactam antibiotics and are used in the treatment of bacterial infections, Cloning technology for the future organs' transplant. We put our effort to make us live longer and stronger. The question which pop up in my mind is 'are we really live stronger and healthier', whatever the answer is 'yes' or 'no', my point of view I could see human is building the strong fence to protect the actual weak body. We are easier to get sick, no strength, easy to allergy form things around us. Our children have been raised inside the hygiene room and condition so how could they develop their antibodies then.
    Human being is a creature which can produce its own antibody; shamefully we have never exercised our abilities and stay in unhealthy lifestyle. Instead of leaning on technology and science, we should establish our strength from inside to outside therefore we would ready to fight with any new mutation of pathogens.

ref: NewScientist, Wiki, Gutenberg.org, abc