Friday, October 28, 2005

Bird Flu

Rational Technology for October 30, 2005

Watch the news these days and you'll always hear some mention of bird flu. The spread of the disease is being closely monitored worldwide, and with good reason. Bird flu, or avian influenza, as it is otherwise known, can spread globally and has the potential to mutate into something more fatal. Thus that also begs the question whether the Dumaguete community is taking steps to cope with such a pandemic if, God forbid, it should take place.

What exactly is bird flu? It is a class of contagious diseases caused by a viruses that normally infect only birds. Wild fowl are asymptomatic carriers and can host the virus without harm to themselves. However, they can transmit it to domestic poultry which are susceptible to the effects of the disease. The viruses have also been known to cross the species barrier and have infected pigs, horses, seals, whales, and humans.

Migratory wild birds are one cause of the global spread of bird flu. However, domestic poultry transported as cargo are also another source. Bird flu can spread in a number of ways: through saliva, through fecal matter, and even through the air. It can also be transmitted by contaminated feed, water, equipment and clothing.

In affected birds, there are two forms of the disease. The low pathogenic form commonly causes only mild symptoms such as ruffled feathers and a drop in egg production. The highly pathogenic form is far more dramatic, spreading very rapidly through poultry flocks, and causing disease affecting multiple internal organs. The mortality rate approaches 100%, often within 48 hours.

In humans, bird flu causes symptoms similar to other types of flu. These include fever, cough, sore throat, muscle aches, and conjuctivitis. In severe cases, it can also cause pneumonia that may be fatal. The severity of the infection depends to a large part on the state of the infected person's immune system.

H5N1, the strain of the virus that is thought to be spreading today, was first shown to have passed from birds to humans in 1997 during an outbreak of avian influenza among poultry in Hong Kong. The virus caused severe respiratory illness in 18 people, of whom six died. Since January 2004, there have been 47 confirmed cases of H5N1 and 34 deaths in Vietnam and Thailand. H5N1 has mutated so that it is now deadly in chickens and mice. It can now infect cats as well. Furthermore, H5N1 is becoming resistant to drugs commonly used to treat flu.

H5N1 has affected birds in Korea, Viet Nam, Japan, Thailand, Cambodia, Lao People’s Democratic Republic, Indonesia, China, and Malaysia. Work is underway to create a vaccine for H5N1, but this is something that will take time. In the meantime, the primary means of control of avian influenza is through extensive culling of infected poultry, as has been done in Japan, Malaysia, and Korea.

An important thing to note is that while the current strain of bird flu has been known to pass on from birds to humans, it has not yet done so widely. Human-to-human infection has thus far not been demonstrated. Nevertheless, those working with live poultry should exhibit due care.

Other than that, the drive is towards national preparedness in order to reduce opportunities for a pandemic virus to emerge. An early warning system, implemented through close monitoring of birds, can delay initial spread. Something as basic as monitoring of poultry should be in place in Dumaguete.

Top Tips
  • Only those who work or live in close proximity to birds are at risk.
  • Influenza A H5N1 has so far only caused problems in Asia.
  • Those working with ducks and poultry should wash their hands after contact with the birds.
  • Don't touch your face with your hands. If you don't touch your face
    with your fingernails you should stop the virus entering your body through
    the mucous membranes of your eyes or nose.
  • Wash and dry your hands thoroughly with soap and warm water every time
    you go to the toilet and any time you handle live birds, raw poulty or
    uncooked eggs.
  • Regulary perform warm facial dips to inactivate virus cells and wash
    them out of your nasal passageways.
  • Children are at particular risk from bird flu, and should be kept away from poultry and ducks.
  • If you develop symptoms of flu talk to your doctor.
  • Those who are particularly at risk from flu and its complications, such as the elderly and those with respiratory or heart disease, should consider vaccination each year.

    Supplemented with information from one of the commenters to the original story.

  • BBC
  • WHO
  • Wikipidia