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If there’s a pandemic, will there be enough vaccine?ASK THIS | April 30, 2006Some questions about avian flu are answered and others raised in an authoritative report by a dozen medical experts. We examined one issue – vaccines – and found the U.S. and the rest of the world won’t be anywhere near ready in an emergency. By Sam Kean Q. The United States has laid aside money in the case of a pandemic flu, but how quickly can vaccines be produced? Have any “candidates” for pandemic influenza vaccine been pre-tested, to expedite later approval? Q. Are provisions in place to ensure that third-world countries receive adequate protection? How do Mexico and Central America fit into this plan? Q. Which drugs and vaccines have U.S. public health officials purchased (or contracted for)? Medically, are these the most effective? What about economically? Who will receive priority, and how will officials ensure they do? A new report written by a dozen medical experts reveals that the worldwide availability of flu vaccines would be woefully inadequate in the case of a pandemic flu outbreak, especially in countries where the population is at highest risk of infection. The news comes from the Influenza Report 2006, a study that combines layman-friendly content with technical medical information. Though the population of the world exceeds 6 billion, only 900 million single-dose flu vaccinations can be produced in a given year. This number assumes that all available manufacturers will produce vaccines at full capacity. To arrest the progress of an outbreak, however, most experts believe that double, or “bivalent” doses would be necessary. “In an ideal world,” the authors state, “12 billion doses of monovalent vaccine would be available in order to administer two doses of vaccine to every living human being.” According to the United Nations population clock, the world population has actually pushed past 6.5 billion, which would translate to an additional billion vaccinations. Furthermore, those vaccines are concentrated in countries that already have stable and wide-reaching health systems, such as the United States, Japan, Germany, France, etc. Citizens in subsistence-based countries (e.g., in East Asia, where most deadly flu strains originate because of close contact with farm animals) have little or no coverage. In 2003, the authors note that “only 79 million were used outside of these countries and Western Europe.” The discrepancies between populations and doses and between the first and third worlds arise from the immense cost of producing flu vaccines: They are cultivated in evacuated chicken eggs, an intensive process that forces health officials to guess in February which flu strains will be most deadly come September. The current situation would be troubling even if an outbreak were only a possibility. However, the report takes the position that flu pandemics are not only probable but inevitable: “The most important thing to remember when talking about pandemic influenza is that its severe form has little in common with seasonal influenza. Pandemic influenza is not business-as-usual influenza. Bear this in mind. You wouldn’t call a tiger a cat. [. . . ] Major pandemics have occurred throughout history at an average of every 30 years and there is a general consensus that there will be another influenza pandemic.” To prepare for an outbreak, the authors recommend that vaccines for future “pandemic-like” flu strains move to clinical trials today and that both the production and consumption of flu vaccines increase. Conducting clinical trials now for pandemic candidates will allow doctors to approve vaccines more quickly if pandemic strikes, while increased consumption will weaken current influenza strains and make future production more economically feasible, presumably due to the economics of scale and by providing pharmaceutical manufacturers with more incentive to produce vaccines. According to the CDC, current vaccines for adults in the United States cost between $20 and $25 per dose. Children’s doses cost between $11 and $14 per dose. For healthy, “primed” adults under the age of 65, single-dose vaccines have efficacy rates of 80-100%, and “unprimed” adults move into this range after two doses. Other populations have lower efficacy rates: cancer, for instance, drops efficacy to 18-60%. The elderly and small (or unhealthy) children are also at much greater risk of infection. Overall, then, even if current vaccines were freely available, many would still face the risk of infection, especially from an aggressive strain of flu. Genetic engineering technology could improve this outlook: “In 10 years from now,” one author notes, “it is likely that we will look back on our current influenza vaccines and think of them as primitive.” The most promising avenues trick the body into producing an immunological response without exposure to the virus itself, eliminating the need to capture, cultivate and distribute doses. In addition to technology, smart public policies can mitigate the deadliness of malignant influenza. The report outlines three key tactics that government and other health officials should take: contain the victims, administer drugs and distribute vaccines. The report takes a cautious approach to containment, noting only that, in extreme cases, border control (e.g., screening passengers on international flights) and quarantining flu victims might be necessary for the public good. While vaccines aim to prevent infection, drugs attempt to curb the malignancy of the virus after the infection. For avian flu, doctors predict that the drug Tamiflu (chemical name oseltamivir, produced by the Swiss firm Hoffman-La Roche) will prove most effective in combating H5N1 flu. According to the San Francisco Chronicle, Tamiflu costs around $60 for a 10-day treatment. Various media outlets reported that Taiwan announced in October 2005 it would violate the patent on Tamiflu and produce generic oseltamivir for its citizens. For any public policy approach to succeed, political commitment is fundamental. Commitment includes not only anteing up money and allocating resources, but honesty and cooperation among various nations and levels of government. The report states: One of the most significant factors is political and social willingness to acknowledge and report disease dissemination. Without this key factor, no further national action to prevent pandemics can take place. High-level political support and commitment are necessary to develop a preparedness plan. Increased regional collaboration and networking may not only lead to the mutual support of people involved in the planning, but can also be used as an instrument for increasing international pressure and thus political commitment. One valuable feature of the report is its comprehensive approach and willingness to consider a flu outbreak from multiple angles. For instance, by examining the history of flu pandemics in the 20th Century (and any given century can expect three of them), doctors dispel the notion that influenza attacks like a tsunami, in one deadly sweep: “Pandemic influenza is not always like a sudden storm, followed by a return to clear skies. Instead, mortality rates can remain elevated for several years.” They note that although the “truly malignant” 1918 virus did most of its damage that year, countries such as Australia were not hit until 1919 or later. In addition to lives lost, authors also touch on the economic devastation a flu pandemic would bring: “Records of past pandemics, especially that of 1918, show that a pandemic event may have disastrous consequences for any country due to its impact on the national socio-economic and political structures.” The report is well-stocked with pictures and explanatory graphics, and for those who wish to investigate the matter in more detail, it includes chapters on the virology of avian influenza and the immunology and pathology of the disease in humans. The last few chapters—detailed information about drugs and vaccines, including results of clinical trials—could prove invaluable as a quick reference guide when evaluating the specifics of any offered public health plans.
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