A major worry of pandemic threat due to Avian influenza A (H5N1) virus had been emerged. Many study estimated that its consequences could have result in economic costs in approximately $675 billion in United States. As of time, this virus continues to evolve into antigenicaly distinct clades, expanding to include wild migratory birds, and outbreaking among birds in more than 30 contries.
The virus itself can cause human illness, and can transmitted from human to human. And this condition is alerting WHO for pandemic influenza-higher numbers represent seriousness. But currently this virus is not yet pandemic because of its inefficiency of human to human transmission. If the transmission is getting efficient and current mortality rate reach 50 percent decreased, we will be in the midst of serious pandemic.
The key to maintain the public health is developing and stockpiling of vaccines which are safe and effective for decreasing the morbidity, mortality and economic effect of pandemic influenza. In this journal, the author said that the vaccine was produced from a human isolate of a virulent clade 1 influenza A (H5N1) virus with the use of a plasmid rescue system, with only the hemaglutinin and neuroamidase genes expressed. The hemaglutinin gene was further modified to replace six basic amino-acids-associated with high pathogenicity in birds at the cleavage site between hemaglutinin 1 and hemaglutinin 2. And the immunogenicity was assesed by microneutralization and hemaglutination-inhibition assays with the use of the vaccine virus.
However, recently worlwide manufacturing capacity for influenza vaccine is estimated at only 900 million doses, it means only 75 millions persons could be fully immunized. Immediate development of antigen sparing vaccines to increase the number of doses are imperatived. It suggested influenza vaccine are safe, immunogenic, and have the relevant advantage of cross-protection against other influenza strains.
With greater understanding of science, the experts have the capacity and the responsibility to develope multiple, paralel avenue of vaccine. An efficient, rapid, high yield, low-cost manufacturing, potentially other pandemic influenza virus and the rapid movement of those vaccines into clinical trials. The co-worked and synchronization among countries, concerning liability and intelectual property, ensuring the efficiency of clinical trials will be needed to develop and manufacture of candidate vaccines.
Gregory A. Poland, M.D, from the Mayo Vaccine Research Group, the Program in Translational Immunovirology and Biodefense, and the Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minn is the author of this journal. You can enjoy this medical journal in : Full Text and PDF Format.
Or maybe you interested in reading this book : Avian Influenza Virus (Methods in Molecular Biology)
