AVIAN INFLUENZA-BIRD FLU

AVIAN INFLUENZA-BIRD FLU

Bird Flu has been one of a common existent form of infections in birds from way back but Avian Influenza, the most talked about subject is one of the types of bird flu that has been discussed most and been brought under microscopic observation as experts study the strains of certain viruses that have said to have spread to humans and have been identified as the possible reason for human deaths. Though the bird viruses are limited to their species, the bird flu under study is the one where the virus has strengthened itself to a more active stage with a mutated form of strain that threatens to turn into a major pandemic if not checked in time where large and urgent measures have to be taken to control the on spread of this infection which might have devastating effects on the human population by turning pandemic (spread of potential and and possible lethal disease worldwide).

First noted in Hong Kong in 1977 when people were found to have contracted such flu infection and reportedly died. This virul strain was again found to have been carried far over and reports of its infection kept coming in from many countries like Malaysia, Vietnam, Thailand, Cambodia , China, Laos, South Korea, Canada and now in France, Egypt, India and Nigeria.

The human immune system does not have the type of antibodies required to resist the virus that has been hitherto prevalent in birds and animals. The virus when active, infects by settling in the lungs of its victim and plays havoc with the respiratory tract causing distress and does not respond to the prescription human antiviral drugs and medications.

Since there is no immediate known cure for such a critical pandemic like situation, methods like culling the infected birds and animals and then disposing off the carcasses in appropriate manner is being done. The bird flu is said to spread from through many sources like land, water or air.

The flu virus when active, will quickly kill the wild birds as well as domesticated variety, spreading through to others rapidly and moves on for miles from bird to bird thus infecting more and more of them since this flu is highly contagious. This bird flu virus may be limited to particular species as long as it carries the same genetic material, but the moment it shifts itself to combine to combine with the human form of influenza virus, it results in a new mutation and tends to become very much active and in the process infecting humans when they come in contact with infected birds or infected surfaces and surroundings. This way the virus evolves to a new pattern of strain which becomes difficult to control since it is very powerful and highly resistant to drugs and medicines unless research offers us something new that can contain it.


What is Bird flu ? Or to be more precise.....Avian Influenza ? 

Avian Influenza literally means, Bird (Avian) Flu (Influenza Virus) There are many strains of viruses of influenza in birds. Noticeably among them is H5N1, which has been the topic of concern since the outbreak of which has said to have taken human lives in Asia. Commonly referred to as bird flu, this particular virus of influenza is contagious was found to have infected birds in particular and reported to have spread to new places with the birds when they fly from place to place and migrate across continents. The flu viruses are observed to naturally occur in wild birds and infests in their intestinal tract. The wild birds then carry this virus with them to different new locations thus spreading it to the more vulnerable domesticated variety of birds like Turkeys, Chickens, Ducks and Pigeons etc. 

Though the effect on the wild birds are notable lesser, their domesticated counterparts seem to have very poor immunity against this H5N1 strain. Hence they are prone to sickness and immediate deaths on getting infected.


Does the Avian Influenza Virus ( Bird Flu ) infect humans ?

Normally the more common of the bird influenza viruses do not effect humans in general, but cases were first detected in 1997 and now the recent spate of reported suspected cases which are yet to be clinically cleared  wherein the bird flu virus was thought or suspected to have infected humans. This particular strain of contagious H5N1 virus was reported to have transferred to humans through Live stock specifically Poultry. Since no one can predict how and when a pandemic (world wide spread of disease) may start, extreme care and caution is advised while dealing with given situations to do best of what we can.

How does avian influenza (Bird flu) Virus differ from human influenza virus ? 

Bird flu virus

There is a type of virus called the Type-A and within this Type-A influenza virus there are many subtypes which differ because of the proteins found on the surface of the type-A flu virus. Certain proteins called [HA] Hemagglutinin and [NA] Neuraminidase are the reasons for the different subtypes of Type-A flu. Then there are about 16 Virus subtypes of HA and 9 subtypes of NA within the type-A flu virus. These different HA and NA protein subtypes can possibly give more combinations of further subtypes. Birds are found to have all the subtypes of type-A virus.

Human flu virus

Influenza virus which widely effects humans is known to have three subtypes, namely H1N1, H1N2 and H3N2. These human flu-A viruses are always changing and mutating from time to time adapting themselves to new conditions and hence infecting humans. There is a possibility of the type-A human flu virus gene to have come from birds.

Bird Flu symptoms in humans

Like any other symptom of flu in humans, the bird flu symptoms too are mostly the same except a few but mainly seen is sore throat, cough, pneumonia, fever, eye infections, muscle pains to respiratory problems as well as complications which might eventually turn life threatening. Sometimes the symptoms depend on the type of subtype virus that causes the infection.


In birds the virus is spread through nasal secretions, saliva and faeces. Those birds which come in contact with these contaminations mainly excretions or those surfaces which are contaminated by other sources, are prone to the infections.


The bird flu virus infections in humans are said to be contracted through infected poultry stocks or their contaminated surfaces. Cleaning of hands frequently and maintaining hygienic practice is advised to check the infection routes. Washing of hands with soap and use of hand sanitizers are good for keeping hand clean as the transmission of infection is more through the touch of hand. 

what is the treatment for Bird Flu

Though prescription medicines of human flu virus are expected to work as prevention for most of the bird flu infections, The flu viruses are always mutating and becoming highly resistant to drugs and medicines and so medicines may not always be effective.


To what extent can bird flu be risky to human lives.


Though the risk factor of bird flu infection to humans was considered low, the latest outbreaks point towards the human interaction with birds and frequent contact with domesticated breeds of poultry like Chickens, Turkeys and ducks etc are a cause of concern as we never know when and how the infection might have transferred by the wild birds to the domestic stocks. There are innumerable ways this spread of infection is possible. The wild birds fly from place to place and some known to migrate across continents carrying with them the deadly virus. Their droppings in the waters, land surface and mingling with the local area birds, is how the virus can spread its tentacles. Once it infects even one domestic bird, it is obviously in a position to spread to the others of its kind. Those which are contracted to this particular strain of deadly virus (H5N1) are sitting targets of infections and possible deaths.

What ways are we at risk of exposure to the Bird flu.

In human beings, the influenza virus is contagious and is spread through sneeze, cough and touch. Inhalation of air which is polluted with flu virus, gives it an entry into the lungs from where it basically operates. In the farming sector, the animal excretion and manure infected with the virus contaminates the soil around. Inhalation of the dust particles from this soil is one way of acquiring the virus. Shoes, contaminated feed, cages or farm implements can be considered some of the other source of transport of the virus which tends to stick on their feet when they move around the infected places. some studies have suggested that even one gram of infected bird's manure can be potential with virus enough to spread and infect more than a million birds.

People living around poultry processing plants, playing around places where culled birds were disposed, swimming in lakes or shores where the infected birds move around dropping and contaminating water, and inhaling of infected air of the contaminated areas where infections thrive, are the most at risk of the viral disease. 

Some of the other sources of virus can be eggs from the infected poultry, uncooked bird meat and bird products for consumption purpose etc. Thus poultry products should be carefully handled. Since the virus is strong enough to survive in various conditions of temperature fluctuations, the possibility of frozen products carrying the virus cannot be ignored.

What are the vaccines available to protect oneself from the avian flu ? 

Though no vaccines have yet been effectively identified or made available for protection against the Bird Flu [H5N1] or other certain subtypes, research is underway to develop one soon. Though two of the common antiviral drugs Rimantadine and Amantadine were found to be ineffective towards H5N1 few medications like Oseltamavir and Zanamavir may probably work to check the flu caused by H5N1 virus which is yet be proved clinically and needs lots of further research in the medical field to prove it's potency.

Some answers to important questions.

1) Will bird flu turn pandemic ?

Taken facts into consideration there is a very strong reason to believe that a bird flu can become pandemic if not checked in time. Though initial studies have put the researchers at a mixed opinion, flu viruses have known to keep mutating and changing again and again thereby becoming more resistant to the old flu medicines. 

What researchers are worried is that when a human infected with human flu simultaneously contracts bird flu, then there is a strong possibility of the two flu viruses getting mixed and a new strain of virus can emerge which is a new mutated form and no medicine may actually be effective giving it the chance to cause epidemics or a pandemic. The other way can be that the bird flu virus may change into a form where it will be adaptable to infect humans and then cause its spread. Humans have a weak or no immunity against these type of new viruses giving a reason to be extremely cautious and prepared. Earlier in history pandemics have been recorded where millions of human lives were lost, like the terrible plague of the early twentieth century. Since the bird flu has caused a lot of panic because of its epidemics in poultry and other wild birds, it is a cause of concern.

2) What is the cure for bird flu (Avian Influenza)

There is no known cure for flu viruses, medicines in human flu slow down the progress of the virus and weakens them if the drug is taken in intial stages of the infection. The Bird flu virus is resistant to most of the human flu drugs though some observations suggest that H5N1 is sensitive to Relenza and Tamiflu.

3. What are the drugs available for Bird flu treatment and prevention?

Relenza and tamiflu can be tried for bird flu treatment or prevention as they are the only drugs that the virus seems to be sensitive to. Though no vaccine for immunization is immediately available off the shelf, the research is underway with some promising developments but it is still time for the vaccine to prove its high level of potency and to be made available throughout the world. The task of producing large quantities of antiviral drugs and vaccines in a time proportion to the time of possible pandemic spread of H5N1 is the challenging task that lies ahead.

5) Does consumption of poultry products cause bird flu infection? 

Since the meat and eggs are subject to heat when cooked the flu virus doesn't survive the heat, hence it is safe to cook well and eat. Precautions have to be taken in the case in handling of raw meat of poultry as the virus can survive in raw meat. Good hygienic management and disinfections is important.

6. How can bird flu be transmitted to humans ?
The known and reported cases of bird flu have been suspected to have caused by people handling poultry infected with H5N1 and coming in contact with contaminated poultry waste and manure. Since the flu virus is highly contagious and such infections are known to spread from person to person when in close contacts and surroundings of infected atmosphere, care is advised as a precaution just as in any case of other flu care. Few indications suggest that the bird flu can transfer from human to human on prolonged exposure to each other on close contacts.

7. How many types of bird flu are known ?

There are many strains of flu viruses in birds out of which H5N1 is the most importantly discussed strain. this particular virus strain is being studied in-depth because it has reportedly taken human lives and being a new viral mutant subtype it does not have a fool proof cure and no strong medicine available for immediate access if required for prevention and cure unless research comes out with something proven. A few other subtype of virus strains were noticed earlier like H7N7 in year 2003 causing redness of the eye, but these were not seen again as they were reportedly contained.


8. What care do i take to protect myself from the bird flu?

The best care is to be hygienic and always wash hands with good soap or sanitizers and keep a close watch on the developments and update ourselves through news and information sources. Avoid close contacts with suspected infected surroundings and contaminated surfaces. Make more awareness among the society of the least suspected sources of transfer of the virus ( air, land and water ).

                                                                         Disclaimer

Readers are advised to consult their Doctors for right medical guidance. The Information furnished herein is only a compilation from  news and articles available from various sources and has been done in the interest of public.  We do not take any kind of responsibility for anything that may be interpreted from this article.