Infectious disease is one of the many health problem deserve much of our attention, since back to years and years ago till now. The spectrum of these diseases is expanding with the occurrence of new diseases which i. e. the new emerging diseases and the come- back of those once we thought to have been eliminated, the reemerging diseases.
If I ask you, what's the disease you know best which is highly infectious? Easily spread? The spreading affect not only family in house, not only community in one city, not only citizens in one country, but worldwide, GLOBAL. You may name a few, but I'm pretty sure that one of the answers would be INFLUENZA.
It can be flu we all used to experience (at least once in a lifetime, but I'm sure more) since we were little, it can be avian flu, or even swine flu. I chose to discuss about Avian flu the fact that the trains of avian influenza A which causes avian flu is a highly pathogenic H5N1 virus and cause tremendously great effects, globally.
"The root of cause"
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Avian influenza is an infection caused by avian (bird) influenza (flu) A viruses. These influenza A viruses occur naturally among birds. Wild birds worldwide get flu A infections in their intestines, but usually do not get sick from flu infections (non pathogenic influenza virus). However, avian influenza is very contagious among birds and some of these viruses can make certain domesticated bird species, including chickens, ducks, and turkeys, very sick and kill them.
"How we, human get it"
During an outbreak of avian influenza among poultry, there is a possible risk of infection for people who have contact with infected birds or surfaces that have been contaminated with secretions or excretions from infected birds.
You see, there are 2 main concerns very much highlighted of its effects toward human health:
1. H5N1 virus has caused by far the greatest number of human cases of very severe disease and the greatest number of deaths. It has crossed the species barrier to infect humans on at least three occasions in previous years: in Hong Kong in 1997 (18 cases with six deaths), in Hong Kong in 2003 (two cases with one death) and in the outbreaks that began in December 2003 and were first recognized in January 2004.
2. The risk that the H5N1 virus – if given enough opportunities – will develop the characteristics it needs to start another influenza pandemic.
"How influenza pandemic happens and can start another"
The virus has met all prerequisites for the start of a pandemic save one: an ability to spread efficiently and sustainably among humans. The virus can improve its transmissibility among humans via two principal mechanisms.
It's an event in which genetic material is exchanged between human and avian viruses during co-infection of a human or pig. Reassortment could result in a fully transmissible pandemic virus, announced by a sudden surge of cases with explosive spread.
2. Adaptive mutation
A more gradual process, whereby the capability of the virus to bind to human cells increases during subsequent infections of humans. Adaptive mutation, expressed initially as small clusters of human cases with some evidence of human-to-human transmission, would probably give the world some time to take defensive action, if detected sufficiently early.
- "New Emerging Diseases: Avian Influenza, Swine Influenza, SARS", lecture by dr. Titik Nuryastuti, M. Si., PhD.
- WHO | Avian Influenza ("bird flu")