A virus primer
If you're new coming to the bird flu discussion, here are some things you should know:
A growing threat
The deadly strain of bird flu, known as H5N1, first appeared in Hong Kong in 1997. A campaign to kill infected birds stopped the virus then, but it re-emerged in Asia in 2003. Since then, it has crept across Asia, killing people who became infected through contact with birds, usually chickens in their family flocks.
- The infection rate in humans is increasing after more than 48 countries across three continents reported initial outbreaks in birds this year. In 10 countries, H5N1 has killed at least 131 of the 229 people known to have been infected since late 2003, according to the World Health Organization.
- As the sick birds have multiplied, so too has the alarm. Even the famous ravens who live in the Tower of London have been moved inside.
- U.N. officials tracking the flu say that the virus has led to the deaths of 200 million birds.
A repeat of 1918?
A true flu pandemic could kill anywhere from 2 million to 100 million people worldwide, scientists and health officials estimate. And that's why they're looking back in history as they assess the potential for a flu pandemic in the 21st century.
- In 1918, the Spanish flu epidemic killed more than 40 million people worldwide.
- “The 1918 pandemic was wholesale destruction, and yet the mortality rate was only 2 percent,” said Dr. Greg Poland, director of the Mayo Clinic Vaccine Research Group and a member of the advisory committee on vaccines for the federal Centers of Disease Control and Prevention. “(With this flu) the mortality rate is 50 percent. That's what's suddenly grabbed people's attention.”
Why this flu's different
Influenza viruses circulate each year and kill thousands — an average of 36,000 in the United States alone. But they are kept in check by vaccines and the immunity that people have from being exposed before. In the case of bird flu, vaccine has not yet been manufactured and people have no immunity.
A deadly strain
This virus also has the ability to settle deeper into cells in the lungs. So in addition to the regular symptoms of flu (fever, cough, sore throat and muscle aches), those infected are more likely to experience pneumonia and acute respiratory distress. They literally drown in the liquid filling their lungs.
Taking precautions
The government recently released a 227-page report detailing plans for dealing with a pandemic. The report emphasizes that businesses and state and local governments should prepare for a pandemic just as they would for a terrorist attack or natural disaster, and not rely on the federal government to do everything.
- Officials have painted dire scenarios about the chaos that would spread in a pandemic, including closed businesses, schools and offices, interrupted food supplies and a shortage of hospital beds for the sick.
- The government is also stockpiling enough antivirals — primarily the drugs Tamiflu and Relenza — to treat 25 percent of the U.S. population should a pandemic occur in the U.S. To date, the U.S. government has purchased 26 million antiviral treatment courses and expects to have on hand a total of 81 million treatment courses by the end of 2008.
FIND OUT MORE:
CALL: Centers for Disease Control, 800-CDC-INFO
–Compiled by Lisa Greene, staff writer
SOURCES: KRT; Los Angeles Times; CDC; pandemic.gov
