Understanding Avian Influenza - “Bird Flu”

What is Avian Influenza?

Avian Influenza, commonly known as “bird flu”, is an infection caused by a virus. Much like human influenza, avian influenza viruses spread very quickly and can have many different strains. These strains are quite different from human influenza strains. People infected by an avian influenza strain will have no resistance to it.

Wild ducks and other migratory waterfowl are the natural hosts of avian influenza viruses. Some wild birds worldwide can carry the virus in their intestines, but do not show signs of illness. Chicks and turkeys are generally unprotected from infection and can get very sick and die with certain strains of bird flu. While some strains cause no disease, other types can cause severe illness and death to the bird. The H5N1 avian influenza strain, a new strain that is spreading in Asia and some parts of Europe, is a severe avian influenza strain.

Places where birds from different areas are brought together, like live bird markets, auctions, shows and swap meets, can provide opportunities for spreading the disease.

South Carolina is a leading state in the nation for production of domestic chickens and turkeys. An infection among its flocks could do significant harm to the state’s economy.

The human risk from bird flu

Health officials are concerned about the threat posed to humans by the bird flu, because humans don’t have a natural immunity to it. The current avian influenza outbreak has infected numerous bird flocks in Asia and has resulted in the killing of millions of birds to limit the spread of the disease. The disease has also killed about half of the people who have been infected with it.

All people infected so far have had direct contact with infected birds. The disease is not spreading from person to person.

Working together to prevent spread of the disease

Public health officials will provide details about preventing exposure and information about where to go for care if you become sick. Emergency health information will be provided through radio, TV, newspapers and the Internet. Prevention efforts will focus on limiting the spread of the disease.

People who are at high risk of becoming very ill could be advised to avoid contact with large numbers of people. Those who are possibly infected might be restricted to their homes or housed in a health care facility where they can receive appropriate treatment. Someone who is mildly ill will be discouraged from going to work or other public places until they have recovered. DHEC might recommend postponing large public meetings, concerts and athletic events or closing schools for a few weeks.

If there is an outbreak of avian influenza in South Carolina, DHEC and your local health department will provide you additional instructions for protecting yourself. You should tune to local media for the latest information from DHEC and its response partners. Supplies of anti-flu drugs and vaccine will be limited at first. The medicines will be distributed fairly to those people who have the greatest need.

How people get bird flu

Bird flu viruses do not usually infect people. But cases of birds infecting humans have been reported in the last several years in Asia and Indonesia.

Flu viruses change slightly from year to year, making them potentially more infectious. The bird flu is highly contagious among bird flocks and infected birds have rarely spread the virus to humans. Bird flu viruses could change over time and gain the ability to infect humans more frequently. This situation has the potential to create a pandemic outbreak because humans are not naturally immune to it. However, the bird flu has not changed drastically enough to be contagious between people at this time.

Pandemic: A Worldwide Outbreak of Influenza

Pandemic influenza occurs when a completely new virus spreads worldwide. A pandemic could happen if the new virus strain, like the H5N1 avian influenza, became capable of spreading easily from person to person. Past influenza pandemics have led to high levels of illness, death, social disruption and economic loss. Lack of immunity in the general population results in high rates of illness and death worldwide as the virus spreads.

A pandemic is different from a seasonal outbreak or an epidemic of influenza. Each year, existing human influenza viruses cause seasonal outbreaks. An epidemic typically starts from a specific area, such as a village or a country, and moves outward.

No one can accurately predict the next pandemic and the disease that will cause it. However, the H5N1 strain of bird flu appears to be a potential threat because of its ability to change quickly and cause high death rates among the infected.

Information on influenza in South Carolina is posted on DHEC’s Internet site.

Symptoms of bird flu in people

Symptoms of bird flu in humans have ranged from typical flu-like symptoms, such as fever, cough, sore throat and muscle aches, to eye infections, pneumonia and life-threatening lung diseases. The symptoms and their severity may depend on the virus causing the infection.

Treating bird flu

The U.S. Food and Drug Administration has approved four different antiviral drugs for the treatment and prevention of influenza. All four are considered effective against certain influenza viruses, such as bird flu. However, some influenza virus strains become resistant to drugs, making the antivirals less effective.

Vaccine

Routine flu vaccines are developed to provide protection against the human influenza virus circulating each year. DHEC strongly recommends that certain people receive the vaccine. These people are considered to be at the greatest risk of catching the flu and suffering serious illness as a result. However, the routine flu vaccine is expected to provide no protection against bird flu.

Work is underway to develop a vaccine that will protect humans from bird flu. Enough doses of vaccine will be produced to protect a substantial number of Americans. These doses will be stockpiled by the Centers for Disease Control and Prevention (CDC).

A pandemic’s effect on South Carolina

It is impossible to accurately predict what effect a pandemic would have on South Carolina. Experts believe 15% to 40% of the state’s population could be infected in the first wave of the illness. Also, hospitals and physicians’ offices could expect to see many more patients than normal. There is no way to know how many of those cases would be severe or deadly. However, it is almost certain that more people would die during a pandemic than during an outbreak of a more common form of human influenza.

How to protect yourself and others

Human infections of bird flu have occurred in Asian countries such as Viet Nam, Thailand, Cambodia and Indonesia. The patients became infected by contact with birds carrying the disease. No person-to-person transmission of bird flu has been confirmed.

If you will be traveling to Asian countries with known bird flu outbreaks, you should avoid contact with animals in live food markets or poultry farms. Avoid touching surfaces that might have been contaminated by their feces or other body fluids.

As with other infectious illnesses, the most important protection is to practice frequent and careful hand washing. Cleaning your hands often, using either soap and water or alcohol-based hand wipes, helps prevent the spread of disease. Also, cough or sneeze into a tissue and discard it right away. Cough or sneeze into your sleeve if no tissues are available.

What’s being done to protect you

Numbers to know

For more information

This page provides health information for your general knowledge. Talk to your doctor about your concerns about any medical condition. DHEC does not recommend you diagnose or treat yourself for a serious illness.