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A method or strategy which could be used for treatment or prevention of the avian influenza would be mass vaccination.
Vaccination ĘC Basic Information
During vaccination, viruses that are killed with chemicals or heat, mock viruses that are cultivated with their virulent properties disabled, or simply toxic compounds from the virus could be injected into humans, developing immunity and at the same time giving rise to mild or insignificant adverse effects.
What basically happens is that our immune system will recognize these vaccines as foreign particles and destroy them, before creating a whole mass of selective lymphocytes and antibodies ready to neutralize any similar virus before it enters cells or recognize and destroy infected cells before it can multiply.
Problems with Vaccination
Production time ĘC Scientists have always manufactured vaccines by harvesting viruses in chicken eggs. However, H5N1 viruses are as lethal to chicken eggs as well as live poultry. The virus can only be deactivated by altering its genetic code by a process known as reverse genetics , making it harmless to chicken eggs and increasing its rate of replication. Vaccines could only be harvested after this, and the whole process could take up to 6 months. A reaction time of 6 months is far too long when a new outbreak occurs.
Viral mutation - As mentioned in the previous sections (refer to Antigenic Drift And Antigenic Shift), the avian influenza virus has the ability to mutate and change its structure. Thus, the usefulness of the vaccine might be gone in a few months.
Will vaccination be able to fully eradicate/prevent the risk of an outbreak?
Definitely not. Once strains of viruses causing large-scale human infection are present, of which the vaccines could then be made from, an outbreak would have already occurred. It is also impossible to try to anticipate the form what the virus will mutate into and manufacture the deactivated virus prototype as a vaccine.
What role then can vaccination play in the fight against avian influenza? Vaccination is mainly used by overseas travellers to lessen the risk of getting avian or human influenza during their trip to flu infected areas. Also, when a new large outbreak of influenza virus appears, a vaccine could be quickly cultivated and mass vaccination could be carried out, limiting the spread of infection to a small group of people. The vaccine manufacturing process, as mentioned above, could be a long one however, and an enormous amount of people worldwide could have already been infected with the virus by the time a vaccine could be manufactured. Vaccination alone is not enough to allow the world to be able to cope with an outbreak.
Who should undergo vaccination?
As a basic guideline, all people who will be in contact with live poultry should be vaccinated. All children and old adults, or people contracting long-term diseases and thus have weaker immune systems should also undergo vaccination if they are traveling abroad to countries affected with avian flu before, even if they most probably will not come in close contact with live chickens. Vaccination will help to effectively prevent the risk of being infected by both bird and human flu viruses for a temporal period.
Most of the preventive measures currently available only serve to contain and limit the spread of infection; they will not be able to fully eradicate and stop and outbreak from taking place.
Like during the 2003 SARS outbreak, when many countries put in place quarantine measures to cope with the outbreak, similar measures should also be used during the fight against the avian influenza. Relatives of infected persons or people who have interacted with them during their period of infection, as well as travelers who have been to affected countries should be quarantined, so as to minimize the rate of human to human transmission.
Stockpiling of Antiviral Drugs
Countries should have flu antiviral drug reserves so as to be able to cope with an outbreak quickly whenever one is reported, by spraying of disinfectant in the infected area and treating new cases of human infections quickly.
Bird Culling/Ban of live poultry
Close contact with live infected poultry is the main source of human infection. A direct method of preventing the virus from jumping from birds to humans would be to kill infected poultry within the region of infection. Bans on live poultry exports from infected regions should also be imposed, so as to limit the spread of infection and prevent the influenza from spreading across countries. However, this requires quick and efficient communication, so that infected birds could be culled before the virus is able to spread to humans outside the area.
Travel to countries or areas hit with the avian influenza should either be totally restricted, or if not, travelers to be advised to undergo vaccination, avoid contact with poultry, or other preventive measures, so as to prevent the virus from jumping across straits and limit the spread of infection.
Although there are currently no proven incidences of Avian Flu transmission through humans, unhygienic social habits, eg. spitting or passing of human excretion, coughing/sneezing loudly and indiscreetly, in public, should still be heavily discouraged, with fines imposed if possible (like in Singapore where fines were imposed on casual spitting during the 2003 SARS scare), as it is usually through these uncouth habits when people get in contact with bodily fluids of others where viruses are widely transmitted. Other habits like sharing of food and drinks should also be discouraged as these will serve as means through which the virus can be easily transmitted.
People must exercise care especially when consuming poultry products, and avoid eating raw or half-cooked meat and eggs. In fact, all forms of raw food should be avoided as far as possible. There is however no evidence that people can contract avian flu by consuming cooked chicken meat and eggs, as heat treatment will effectively destroy any viruses. As long as it is thoroughly cooked or canned, poultry products available in the market are safe for consumption. People should also be encouraged to adopt a balanced diet which includes fresh fruits and vegetables, as well as regular exercise in order to build a strong immune system.
There is little point having so many methods of prevention, if no one knew about them! People must know the basic how-s, what-s and why-s about avian flu, and most importantly, how they can prevent the risk of ever contracting it. Governmental bodies and the media have the responsibility to ensure that people are aware about vaccination, when and how to get it, as well as what countries to avoid visiting as far as possible. They must also be educated to practice good social and eating habits, as mentioned above.
If everyone could be aware on any rising pandemics and how to protect their children's as well as their own health, there would no disease outbreaks that cannot be prevented.
In order to be able to stop the virus in its tracks and limit the spread of infection to a small area once an outbreak is reported, quick and effective intervention is key. A mixture of vaccination, quarantine measures, bird culling, antiviral drugs and other measures will be able to ensure that infection is confined to a small area once an outbreak is reported, however, the flu will still go out of control if measures are taken to stop the flu only after the virus has already spread to a large area. Thus, nothing is more important than effective communication between poultry farmers and scientists to quickly intervene any signs of flu infection.
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