Bird Flu

1 What is Bird Flu?

Bird flu, also called avian influenza refers to an infection of birds caused by the influenza type A viruses (H7N9).

These viruses are natural inhabitants of wild aquatic birds and can infect domesticated birds such as chickens, ducks, and turkeys.

Avian influenza A viruses are very contagious as the infected birds shed these viruses in their saliva, feces, and nasal discharge.

The two major types of avian influenza A viruses include low pathogenic avian influenza (LPAI) A viruses and highly pathogenic avian influenza (HPAI) A viruses.

The two strains that have been responsible for most human illness throughout the world are H5N1 and H7N9 viruses.

When bird flu occurs in humans, it results in a fatal infection. In the recent years, outbreaks of bird flu have been identified in Asia, Africa, and certain parts of Europe.

Bird flu symptoms develop in human beings who have had closer contact with the infected birds.

In some cases, it has been found that the bird flu virus can transmit from one person to another.

This has been a great concern to health officials worldwide as a global outbreak may result if the virus undergoes mutation into a strain that is easily transmissible among individuals.

Ongoing research is being conducted to invent a vaccine against bird flu.

2 Symptoms

The signs and symptoms of bird flu appear between 2 to 8 days of the infection and may depend on the type of infection.

The LPAI A virus infections in humans cause influenza-like symptoms such as fever, cough, sore throat, and muscle aches.

In addition, a mild eye infection (conjunctivitis) or lower respiratory infection (pneumonia) may occur.

The HPAI A virus infections cause a wide range of symptoms such as:

  • conjunctivitis
  • influenza-like disease
  • severe respiratory disease (shortness of breath, difficulty breathing, acute respiratory distress, pneumonia)
  • nausea
  • pain in the abdomen
  • vomiting
  • diarrhea
  • neurological symptoms such as seizures

Consult your doctor immediately if you develop symptoms such as fever, cough and body aches, especially if you had recently traveled to places where bird flu is prevalent.

Also, be sure to inform your doctor if you had recently been to any poultry farms or open-air market places.

3 Causes

Infected birds are the main cause of bird flu.

Bird flu viruses usually do not infect human beings, but rare cases of infection with these viruses have been reported in humans.

Infected birds often shed the virus through their saliva, mucus, and feces.

The virus remains in the air as droplets or dust and when a person breathes in or when a person touches any surface contaminated with these viruses and then touches his mouth, eyes, or nose, the bird flu infection commences in humans.

Being in open-air marketplaces, where eggs and birds are sold in unsanitary conditions can increase your risk of contracting this viral infection.

Also, if eaten undercooked, poultry meat and eggs can transmit bird flu.

It is safe to eat poultry meat if it has been cooked up to an internal temperature of 74°C.

Eggs should be well cooked until the yolk and white become firm.

Human infection with the bird flu virus may occur even after unprotected contact with the infected bird or contaminated surfaces.

4 Making a Diagnosis

Making a diagnosis of bird flu is done by several tests.

If you believe that you have symptoms similar to that of bird flu, do not hesitate to consult your primary care doctor.

Wear a surgical mask during your visit and inform people regarding the possibility of bird flu.

You may be admitted to the hospital if you are severely ill.

History of your symptoms

Make a list of your symptoms and the time for which you have had those symptoms.

Recent exposure to possible sources of infection

Inform your doctor about your recent international travel particularly if the area was endemic to bird flu.

Medical history

Prepare a list of your past medical history, including the health problems for which you are being treated and any medications, vitamins or supplements you are taking.

Make a list of the possible questions you need to ask your doctor in advance.

This helps you utilize most of your time with your doctor in discussing the information you need to know in detail. 

For bird flu, some of the basic questions you can ask your doctor include:

  • What may be the cause of my symptoms?
  • Will I need any diagnostic tests?
  • What is the best treatment approach?
  • Are there any alternative treatment methods?
  • What self-care measures can be taken at home to help ease my symptoms?

In order to make an accurate diagnosis, your doctor needs to know certain information regarding your illness.

Some of the questions your doctor may ask include:

  • When did your first symptom begin?
  • Did you have a fever?  If so, what was your temperature?
  • Were you in close contact with poultry birds recently?
  • Did you travel to a place where there are outbreaks of bird flu?

Samples of mucus discharge from your nose or throat will be taken for testing the presence of bird flu virus.

These tests are performed within the first few days of the appearance of symptoms.

Imaging tests

A chest X-ray will be done to assess the lung condition.

This helps to decide on the proper diagnosis and develop a most appropriate treatment plan for your symptoms.

5 Treatment

The Center for Disease Control (CDC) recommends the use of oseltamivir (Tamiflu), peramivir, or zanamivir (Relenza) for the treatment of human infection with bird flu.

These drugs should be taken within 2 days of the appearance of symptoms.

6 Prevention

The best method to prevent bird flu is to avoid the sources of infection.

Most infections in humans occur after direct contact with the infected birds.

A vaccine has been developed to prevent infection with the strain H5N1 bird flu virus, which has been approved for use by the Food and Drug Administration.

This vaccine is not available to everyone, but the US government is maintaining a stockpile of these vaccines and will release them in the case of an outbreak.

This vaccine can be used early during an outbreak to provide protection until another vaccine, specific to the mutated form of the virus causing the outbreak is developed.  

If you are traveling to Southeast Asia or any other region with bird flu outbreaks, follow these public health recommendations to prevent infection:

  • Avoid contact with domesticated birds
  • If possible, avoid visiting rural areas, crowded farms, and open-air markets
  • Wash your hands thoroughly: This is one of the simplest and best methods to prevent all type of infections
  • Make use of an alcohol-based hand sanitizer that contains at least 60% alcohol
  • Before traveling, ask your doctor regarding a flu vaccine. It will not protect from bird flu, but will reduce the risk of simultaneous infection of bird and human flu viruses.
  • Take precautions while handling and preparing poultry meat, which may be contaminated with salmonella bacteria.
  • Cook meat thoroughly until it reaches a minimum internal temperature of 74°C.
  • Avoid food containing raw/undercooked eggs.
  • Avoid cross contamination: Wash cutting boards, utensils and surfaces that have been in contact with raw meat using hot, soapy water.

7 Risks and Complications

The major risk factor for contracting the bird flu is direct contact with infected birds or surfaces contaminated with feathers, saliva, or feces of sick birds.

In rare cases, bird flu gets transmitted from one individual to another and the pattern of human transmission is still unknown.

People of all ages can get bird flu and the average age varies with the type of bird flu.

For instance, the average age of people affected by the H7N9 virus was 62 and the average age of people affected with H5N1 was 26.

Bird flu may lead to deadly complications such as:

  • Respiratory failure
  • Renal dysfunction
  • Cardiac problems
  • Lung collapse and Pneumonia

Less than 500 deaths due to bird flu have been reported to the World Health Organization since 1997.

On the other hand, the CDC has estimated that seasonal influenza is the reason for more than thousands of deaths occurring each year in the United States.

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