Bird flu, also known as avian influenza, is a type of viral infection that affects birds and can sometimes infect humans and other animals. Although there are many strains of bird flu, only a few of them can cause serious illness or death in humans. In this article, we will explain what bird flu is, how it spreads, what are the symptoms, how it is diagnosed and treated, and how to prevent it.

What is bird flu?

Bird flu is caused by influenza A viruses that normally circulate among wild aquatic birds, such as ducks, geese, and swans. These viruses can mutate and adapt to infect domestic poultry, such as chickens, turkeys, and quails, and cause outbreaks of disease. Some of these viruses can also cross the species barrier and infect humans and other mammals, such as pigs, cats, and dogs.

The most common subtypes of bird flu that have infected humans are H5N1, H7N9, H5N6, and H5N8. These subtypes are named based on the combination of two proteins on the surface of the virus: hemagglutinin (H) and neuraminidase (N). Each subtype can have different variants that differ in their ability to cause disease and spread.

H5N1 was the first subtype of bird flu to infect humans in 1997 in Hong Kong. Since then, it has caused sporadic cases and outbreaks in Asia, Africa, Europe, and the Middle East. H5N1 is highly pathogenic, meaning it can cause severe disease and death in birds and humans.

H7N9 emerged in 2013 in China and has caused several waves of human infections since then. H7N9 is low pathogenic in birds, meaning it causes mild or no symptoms in them, but it can cause severe disease and death in humans. According to the WHO, H7N9 has infected 1,568 people and killed 616 of them as of July 2021.

H5N6 was first detected in humans in 2014 in China and has since caused sporadic cases in several Asian countries. H5N6 is highly pathogenic in birds and can cause severe disease and death in humans.

H5N8 was first detected in humans in February 2021 in Russia. Before that, it had caused outbreaks of disease in wild birds and poultry in several countries across Asia, Europe, Africa, and North America. H5N8 is highly pathogenic in birds but does not appear to cause severe disease in humans. According to the WHO, H5N8 has infected 10 people and none of them have died as of July 2021

How does bird flu spread?

Bird flu spreads mainly through direct or indirect contact with infected birds or their secretions (saliva, mucus, feces). People can get infected by:

• Touching sick or dead birds or their droppings.

• Handling or slaughtering infected poultry or wild birds.

• Visiting live bird markets or poultry farms where the virus is present.

• Eating undercooked poultry or eggs from infected birds.

• Breathing in droplets or dust that contain the virus.

Usually, Bird flu does not spread from person to person. However, some rare cases of human-to-human transmission have been reported among people who had close contact with infected patients or their bodily fluids. There is no evidence that bird flu can spread through casual contact or through properly cooked food.

What are the symptoms of bird flu?

The symptoms of bird flu may vary depending on the subtype of the virus and the individual's immune system. In general, the symptoms may include:

• Fever (over 100.4°F or 38°C).

• Cough.

• Sore throat.

• Runny nose.

• Headache.

• Muscle ache.

• Conjunctivitis (pink eye).

• Diarrhea.

• Vomiting.

• Malaise (feeling unwell).

Some of the people may develop more severe complications, such as:

• Pneumonia (infection of the lungs).

• Acute respiratory distress syndrome (ARDS) & (a life-threatening condition where the lungs fail to provide the required oxygen to the body).

• Sepsis (a serious infection that affects multiple organs).

• Organ failure (when one or more organs stop working properly).

• Death.

The symptoms usually appear within three to five days after exposure to the virus. However, some people may have a longer incubation period (up to 10 days) or no symptoms at all.

Conclusion

Bird flu is a serious threat to human health. However, there are things you can do to protect yourself from infection. By being aware of the signs and symptoms of bird flu and taking steps to protect yourself, you can help to reduce your risk of infection.

I hope this article has been informative. If you have any further questions about bird flu, please do not hesitate to ask.