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Definition

Bird flu is caused by viruses naturally found in birds. Wild birds carry these viruses in their intestines with no ill effects because usually these birds are more immune to the viruses. However, when domesticated birds such as geese, ducks, chickens, and turkeys catch the virus, it can make them very ill and may cause them to die.

 

Causes

Birds pass on this virus through saliva, nasal secretions, and faeces. Any direct contact with these substances or contact with a surface contaminated with these substances (dirt, cages, water, feed) causes infection. Domesticated birds may catch the viruses through direct contact with contaminated wild birds. Humans can contract the virus through contact with infected birds.

 

Symptoms  

·        Sore throat

·        Cough

·        Fever

·        Pneumonia

·        Respiratory failure

·        Muscle weakness and/or pain

·        Sore eyes (conjunctivitis) is seen in some patients

Causes of death and complications are:

• Severe viral pneumonia
• Respiratory distress syndrome
• Multi- organ failure

 

 

History of the Disease

In 1983, a strain H5N2 of relatively low pathogenicity circulated in the US. But, in six months, the virus mutated into a highly pathogenic virus with a death rate of close to 90%. In the end, the epidemic caused $65 million USD and the death of 17 million domestic birds. A similar case happened in Italy, when in 1999-2001 a strain of the H7N1 virus started out with low pathogenicity and within 9 months developed high pathogenicity, and 9 million birds were either killed by the virus or destroyed to halt the spread. Human cases which ended in death were unknown until 1997, where six people in Hong Kong were killed by a particularly virulent strain of the H5N1 virus.

The current epidemic is caused by H5N1 virus. This strain of virus began its rampage in Vietnam and Thailand in January 2004. Within weeks the virus had spread to ten other south East Asian countries. This virus is especially contagious among birds and can be fatal to them. Human infection usually does not happen, although recently there have been more cases of this. Infection is only possible if humans touch contaminated birds or contaminated surfaces. This type of virus alone is not too much of a threat. Scientists are worried that the virus will mutate into a virus which is easily contagious among humans, causing a worldwide flu pandemic just like the one back in the 1910's. This pandemic was caused by a Spanish Flu, and killed 20 million people. Also, in February 2004, a subtype of the virus was detected in pigs in Vietnam, resurfacing worries of meat, as chicken and pork are popular meat.

 

 

Treatment

•  Antiviral drugs (some of which can be used for both treatment and prevention)

 

Prevention

·        Thoroughly wash your hands with soap and water before and after handling chicken meat

• Clean kitchen surfaces and utensils before and after use

·        Cook chicken well by seeing to it that the boiling temperature is reached

·        Do not let chickens roam freely if you own chickens

·        Keep them in cages or pens.

·        Do not place chickens, ducks and pigs together in one area, cage or pen.

·        Do not catch, go near or keep wild birds in captivity

·        Report to authorities any unusual death or illness of chickens and other birds

• Report to authorities any case of respiratory illness with history of exposure to sick or dead chickens and other birds

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