Friday, October 21, 2011

The Lethal Menace

These days all one seems to hear in India is "Bird Flu". The disease which has taken a major part of India in its grip, has not only severly affected the poultry industry of the nation but also it has sent panic bells ringing across the states - from Delhi in the North to Tamil Nadu in the South, to West Bengal in the East, the latter being worst affected. Even the World Health Organisation (WHO) has declared the current outbreak of Bird Flu in India as the worst case reported till date.

In the affected areas, chickens are being culled at a rapid pace, but still the disease is spreading its wings from one district to the other, from one state to another. One primary reason for the rapid spread of Bird Flu is the lack of awareness about the virus which causes the disease. Almost everyone knows that the disease is lethal, but not many know what causes it, how it spreads, and how it can be prevented.

Keeping in mind the scale and spread of Bird Flu virus that has taken its toll in India, Headlines India decided to give its readers an insight into the disease, which first broke out in 1997 in Hong Kong, affecting 18 people and claiming 6 lives.

Bird Flu, also known as Avian Flu, is an influenza caused by virus, which affects birds. It might sound surprising, but the fact is that birds, like humans, are vulnerable to influenza. Influenza viruses can be divided into three types (strains) - influenza A, B and C. Type A is responsible for the deadly influenza pandemics. Type B can lead to smaller, more localized outbreaks. Type C, less common and more stable than other strains, has milder symptoms. Types B and C are usually found only in humans, whereas type A infects both people and animals, including birds, pigs, horses, whales and seals.

Bird Flu is caused by the H5N1 strain of virus, and is a type 'A' influenza. It usually affects chicken and other poultry birds such as ducks. Earlier, human infection was unheard of in Bird Flu. However, the virus spread from birds to humans in 1997, when six people in Hong Kong died of the disease. According to the data provided by World Health Organisation on February 1, 2008, approximately 225 people across the world have succumbed to the disease over the past five years.

It must be noted here that although the bird flu virus is highly contagious, it rarely causes any harm to the carrier. Thus, even while infected with an avian flu virus, the animal does not have "flu". Typically, flu virus is adapted by one species of bird, and in turn spreads to another species. This happens more with the domestication of chickens and turkeys, as the avian flu virus acquired by one species rapidly mutates and infects the other species as well. This rapid spread can be stopped only by killing every domestic bird in the affected area.

The H5N1 strain virus causes avian influenza. The highly pathogenic Influenza A virus subtype, H5N1 virus, is an emerging avian influenza virus that has been causing global concern as a potential pandemic threat. It is simply referred as "bird flu" or "avian influenza".

Over the years, H5N1 has evolved into a flu virus strain that infects more species of birds than any previously known flu virus strain. This strain is deadlier than any previously known flu virus strain, and continues to evolve becoming both more widespread and more lethal.

H5N1 has killed millions of poultry Asia, Europe and Africa. Although human transmission of the virus is rare, the recent cases of human infections have left the health officials worried. Health experts are concerned that the co-existence of human flu viruses and avian flu viruses (especially H5N1) will provide an opportunity for genetic material to be exchanged between species-specific viruses, possibly creating a new virulent influenza strain that is easily transmissible and lethal for humans.

With bird flu engulfing almost the entire nation, where 26 people with suspected symptoms have been kept in isolation, the disease is posing a potential threat to the country. The virus is spreading like wildfire, and in order to prevent the disease from affecting human beings, it is essential to have a thorough understanding of how bird flu affects human beings, the symptoms of the disease, its treatment and prevention measures.

Bird flu is known to scourge millions of poultry birds in a single outbreak. Lately, we have been hearing of the bird flu virus attacking human beings as well. Once the bird flu virus has made its way into the human body, it renders the infected person terribly sick. In some cases, it also causes death.

At a time when bird flu menace has gripped India severely, we must take care to protect ourselves from the bird flu virus. In order to do that, we must understand how bird flu affects human beings. Read on, and know the implications of the H5N1 strain of virus on human beings.

During an outbreak of bird flu, human infection is very rare, as there is a significant species barrier that exists between birds and humans. However, the virus that causes the infection in birds is capable of changing or mutating to infect humans. Since the first H5N1 outbreak occurred in 1997, there has been an increasing number of bird-to-human transmissions leading to clinically severe and fatal human infections. Health officials are concerned that this bird-to-human transmission can lead to a pandemic, or a worldwide outbreak of the illness.

During an outbreak of bird flu, people who have contact with infected birds can become sick. It is also possible to catch bird flu by eating poultry that is not well cooked or through contact with a person who has it. Bird flu makes human beings sick, and in extreme cases, it can even cause death.

Bird-to-human transmission of the avian influenza virus can take place in the following conditions:

Birds shed the virus: Infected birds shed the virus in their droppings, saliva, nasal secretions and even in their feathers. Humans may contract the virus by close contact with any of these, or even by touching an infected bird.

The virus spreads to domesticated birds: Domestic poultry become infected from contact with other infected birds or with contaminated water, feed or soil. Bird flu spreads quickly within a domestic flock and is inadvertently transported from farm to farm on equipment, cages, and workers' shoes and clothing. Heat destroys the virus, but it can survive for extended periods in cool temperatures.
Markets provide pathways to humans: Open-air markets, where eggs and birds are sold in crowded and unhygienic conditions, are hotbeds of infection that spread the disease into the wider community.

Migration of humans and birds: The ease of worldwide travel has the potential to spread bird flu around the globe. An infected person travelling from an affected area to another area may transfer the virus to other people. Similarly, migratory birds can carry the virus from continent to continent along flyways.
Signs and symptoms of bird flu in humans:

In humans, the virus usually develops within one to five days of exposure to the infected birds. Once the virus is developed in the human body, certain changes are noted in the health of the infected person. The common symptoms of bird flu are:

Cough

Fever

Sore throat

Muscle ache

A mild eye infection

In rare cases, some severe symptoms may also be noted. These are:

Viral pneumonia

Acute respiratory distress - the most common cause of bird flu related deaths.

However, bird flu cannot be diagnosed by symptoms alone. So a laboratory test is required.

Treatment of bird flu:

The primary treatment option for bird flu in humans is the flu drug oseltamivir (Tamiflu), which works by preventing the virus from multiplying. However, Tamiflu may not always work, as the bird flu viruses may become resistant to the drug. The drugs must be taken within two days after the appearance of symptoms. These drugs are scarcely available, and hence many infected human beings die due to the non-availability of Tamiflu.

Preventing bird flu:

A bird flu vaccine is the latest way to prevent the infection of the H5N1 virus in human beings. In April 2007, the Food and Drug Administration (FDA) approved the first human vaccine to prevent infection with one strain of H5N1 bird flu virus. This new bird flu vaccine is not available to the public, but the U.S. government is stockpiling it and will distribute it in the event of an outbreak.

The bird flu vaccine is intended to help protect adults aged between 18 and 64 and can be used early in such an outbreak to provide limited protection until another vaccine - designed to protect against the specific form of the virus causing the outbreak - is developed and produced.

Besides the vaccine, the first and foremost way to prevent bird flu, according to WHO, is to handle and cook the poultry with care. Heat destroys the virus, and hence cooked poultry does not pose a health threat. However, handling and cleaning the poultry with care is also important. Some simple ways to prevent bird flu infection are:

Wash your hands well with soap and warm water before and after handling raw poultry and eggs, and dry them with a disposable towel.

Clean cutting boards and other utensils with soap and hot water to keep raw poultry from contaminating other food.

Use a food thermometer to make sure you cook poultry to a temperature of at least 165 degrees Fahrenheit.

Cook chicken until the juices run clear, and it reaches a minimum internal temperature of 165 degree Fahrenheit (74 degree Celsius).

Cook eggs until whites and yolks are firm.

Prevention for travellers:

Since bird flu is highly contagious, it may affect a person travelling to an affected area. By following certain public health regulations, travellers can prevent the infection and spread of the disease through them. These regulations include:

Avoid domesticated birds: If possible, avoid rural areas, small farms and especially any close contact with domesticated fowl.

Avoid open-air markets: These can be interesting places to visit, but they are often breeding grounds for disease.

Wash your hands: This is one of the simplest and best ways to prevent infections of all kinds. When you are traveling, alcohol-based hand sanitizers containing at least 60 percent alcohol are an excellent choice. They are effective, easy to use, don't require water, and are safe for children.

Watch your kids: Keep a careful eye on young children, who are likely to put their hands in their mouths and who may not wash thoroughly.

Steer clear of raw eggs: Because eggshells are often contaminated with bird droppings. Also, avoid mayonnaise, hollandaise sauce, ice cream, and any other foods containing raw or undercooked eggs.

Ask about a flu shot. Before travelling, ask your doctor about a flu shot. It might not protect you specifically from bird flu, but it may help reduce the risk of simultaneous infection with bird and human flu viruses.

According to the Centers for Disease Control and Prevention (CDC), about 36,000 people die of influenza in the United States each winter. And three or four times every century, a flu pandemic sweeps the globe, claiming millions of lives. We, humans, cannot stop the outbreak of a disease, but we can certainly prevent and cure the infection. All we need to do is, educate and and care for ourselves and our family. So, take care, and stay healthy!

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