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.
Each year, approximately 15 million deaths are directly caused by infectious diseases. The secondary effects of infections
cause millions more. Two of the major killers are malaria and HIV, but influenza also represents a significant risk. In September
2008, the World Bank issued a report estimating that a flu pandemic of similar scope to that seen in 1918 could kill 71 million
people worldwide and cost the global economy more than $3 trillion.1 Although this is a worst-case scenario based on past experiences, the differences in transmission and severity shown by the
outbreaks of avian flu in South-East Asia in 2003 and this year's swine flu have highlighted how unpredictable such a virus
Although the effects of each pandemic will vary greatly, depending on the nature and severity of the disease, the threat applies
to all corners of the globe, from major capital cities to rural areas of developing countries. In addition, pathogenic viruses
such as HIV and influenza mutate rapidly, which is why the HIV virus we encounter today is very different from the strain
that first emerged in the 1980s. Consequently, resistance to the antiviral drugs in circulation develops very quickly and
as the speed of development of new treatments lags behind, we are left increasingly exposed to the effects of infection. If
we also take into account the fact that infectious diseases are the second leading cause of death globally, then it is clear
that we must have a robust strategy in place to address the threat of a pandemic.
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.