Even with care being given to isolate and destroy birds, Avian flu continues to bother Asian and some European producers. Both China and Turkey reported more birds were destroyed this week to prevent spread of the disease. Since 2003, more than a hundred million domestic birds have been destroyed in Asia and parts of Europe. More important than the economic impact to producers is the potential for a human flu pandemic. Most bird flu strains make only poultry and other fowl ill. The strain that has health officials around the world concerned is H5N1. This virus is fatal to birds and has killed more than 70 of the 140 plus human cases that have been reported since 2004. So far, more than 95 percent of those cases have been in eastern Asia.
Researchers at the Centers for Disease Control in the United States have been working on a vaccine to stop the virus. CDC officials are concerned that if a pandemic caused by H5N1 were to occur in the near future there would be no vaccine to combat the virus. Currently, doctors at the CDC are recommending flu shots as a preventative. Though the shots won't stop H5N1 they will prevent infection from more than one strain of the flu.
For all but a tiny percentage, infection has been caused by contact with infected birds or their feces. The CDC is reporting a limited number of human-to-human cases but the virus has not been strong enough to infect more than one other person. As yet, the H5N1 strain has not mutated to spread in large numbers. This week, CDC officials announced that they have prepared emergency plans to control an outbreak if it occurs. The measures include closing schools and quarantines limited to individual families.
One of the theories for the spread of the virus was through the migration of wild birds. The theory was that birds flying from Asia would carry the flu to other countries. This idea was called into question last week when scientists announced only a limited number of cases had been reported in countries along migration routes. In some instances, no cases of H5N1 were found in wild flocks.
In China, there have been 26 reported human cases of bird flu caused by H5N1 and three deaths. To prevent further spread of the flu the Chinese government has been taking precautions. An effort to inoculate all 5.2 billion birds in the domestic Chinese poultry flock is underway and a vaccine for humans is reported to be almost ready. Last week, the government-controlled press reported Chinese health officials were ready to begin mass production of the vaccine once human trials are completed.
With no other way to control the spread of the disease past destruction of infected birds, the Chinese government is concerned cases of H5N1 will spike in January and February. These months coincide with the Lunar New Year when large numbers of birds are transported from place to place for consumption at various festivals.