Although the worldwide response to the swine flu outbreak of early 2009 has shown that we have come closer to being prepared for future flu pandemics, emerging diseases and new influenza strains still present a tremendous threat, with the potential for disastrous effects to global health and both local and global economies. A major limiting factor in preparedness is still the ability to manufacture an adequate number of vaccine doses, in a short period of time and in the right location, when an outbreak occurs. The following article discusses current developments and what could be done in the future from a technology and policy perspective to improve our capability to cope with pandemics.
One of the best ways to combat the spread of infectious disease is through the implementation of an immunization program. Immunization has eradicated smallpox, reduced the global incidence of polio by 99%, and dramatically decreased many other causes of illness and death.2 Countries around the world are now looking to vaccines and immunization as the way forward, and the World Health Organization (WHO) Department of Immunization, Vaccines and Biologicals has set for itself the goal of attaining "a world in which all people at risk are protected against vaccine-preventable diseases."3
Over the past eight to nine years, and especially since the SARS and avian flu outbreaks, many governments have concentrated their efforts on developing preparedness plans. Increased stockpiles of vaccines and antiviral drugs, finance set aside for vaccine development and research, and a focus on education of the public—all played their part in ensuring that when swine flu emerged earlier this year, we were more prepared. There is still a huge gap, however, between the level of vaccine availability and demand, and we still have a long way to go before we have the technology, manufacturing capacity, and responsiveness required to combat a pandemic on a scale based on the 1918 incident. Because vaccination is a key element in pandemic preparedness, what more could we do to ensure that the next global pandemic has as little impact as possible, both socially and economically?
Although we are prepared for the next flu pandemic with stockpiles of antivirals and vaccines, these projects tend to be localized, with some countries holding enough to cover their own population and others falling well short. However, even those countries with large, carefully stored reserves of antivirals may not be protected in the event of an outbreak because of increasing viral resistance to currently available medicines.
In addition, stockpiling of vaccines relies on being able to predict which virus, and which particular strain of that virus and with which traits, will strike next. Therefore, our biggest future pandemic threat comes from new emerging diseases and virus strains, which we know nothing about. In the case of the 2009 swine flu pandemic, many doses of vaccines were rendered useless because they were targeted at the avian flu strain H5N1, demonstrating that even here we need to adapt our approach. Also, vaccines are often relatively unstable because of their complexity, more so than any other class of biopharmaceuticals, and therefore, are difficult to transport and store becasuse they require controlled temperature conditions.