The Latest on the Bird Flu Threat

With all of the changes going on in the world of medicine, it is hard to stay on top of all of the latest developments. Here are some of the important statistics and information as of October 2006.

As of October 31st, 2006, there have been 256 total confirmed cases reported to the World Health Organization since 2003. Of those cases, 152 were fatal. The countries that have had confirmed cases of the bird flu include: Azerbaijan, Cambodia, China, Djibouti, Egypt, Indonesia, Iraq, Thailand, Turkey, and Vietnam. Vietnam has been the hardest hit, with 93 cases and 42 deaths, however none of these were in 2006. Indonesia had the highest instance of outbreak for 2006, including 53 cases with 43 deaths.

In September of 2006, the WHO held a convention among 22 laboratory directors and senior scientists who were currently working on research regarding different strains of the bird flu and the possibilities of a future pandemic. While all strains were considered for the discussions, there was specific emphasis on the H5N1 strain – the one currently responsible for human deaths. The discussion focused on the following: methods of detection and diagnosis for human infections; different antiviral drugs and vaccines to protect humans; findings from countries with recent outbreaks in regards to animal surveillance; and information on the virulence of H5N1 viruses. These topics covered issues involving the severity of the disease, role of migratory birds, and genetic factors that influence humans contracting it. It also covered diagnostic limitations, vaccination policies, and the several distinct genetic groups of H5N1 viruses in different parts of the world.

Several recommendations were made. They included: developing a reliable diagnostic test for use with human patients; publishing recommended tests as well as possible faults on the WHO website; come up with ways to evaluate the effectiveness of potential pandemic vaccines; monitor the current H5N1 virus strains to look for patterns of resistance to antiviral drugs; look into why younger people are more susceptible to infection; look for genetic predisposition of individuals in contracting the disease; introduction of poultry vaccinations in area where culling is impracticable; standardize poultry vaccines; as well as other topics.

The current detection and diagnosis of human H5N1 infections was discussed. Serological methods were discussed for confirmation, particularly in cases where inadequate samples were available. Seroprevalence studies were discussed briefly, but were only of significance in actual poultry workers and not the general population. RT-PCR tests use gene fragments and are highly sensitive, but the risk of cross-contamination is high as well, and many quality controls have to be run in order to assess the accuracy. Because of these factors, and the genetic diversity among the different H5N1 viruses, scientists are finding it very difficult to create a quick and easy test to use in the field.

The status of vaccine development was discussed at the conference. Results have been mixed as to whether or not different vaccines will offer any protection against the virus should a pandemic situation occur. Trials of the vaccines are in process in Europe, the U.S., and Japan. Along similar lines, resistance to antiviral drugs was also looked at. Clinical trials of new antiviral drugs are currently underway, searching for a new defense against the infection.

Surveillance of birds and other animals has also increased, to monitor the spread of the bird flu. Ornithologists have proved useful in keeping track of the endless information from migratory birds, as well as the different responses to the virus being seen in different species. These findings can assist with testing and prevention strategies against the virus.

Going to the World Health Organizations website and other Internet sources can help keep you on top of any new information coming out regarding the bird flu and other diseases.