Innovation in influenza vaccine development
Each year, influenza causes approximately 250,000 to 500,000 deaths worldwide and 3 to 5 million cases of severe illness. More than 1 billion people are infected with the influenza virus annually. Pandemics—worldwide epidemics—generally occur about every 40 years, with the last pandemic happening in 1968. The most severe influenza pandemic, in 1918, infected up to 50 percent of the world’s population and caused 20 to 50 million deaths worldwide. Some estimates show that a highly virulent pandemic strain in today’s interconnected world could cause up to 100 million deaths.
Public health officials agree that the current outbreak of influenza A(H1N1) requires governments to continue with surveillance and with implementing pandemic plans. The World Health Organization has elevated the pandemic alert from level 5 to 6. While it may be time to act strategically, public health leaders agree that it is not time to panic. Efforts are being accelerated to identify and manufacture appropriate vaccines, to ramp up manufacturing processes, and to reinforce health systems.
The emergence of the new influenza A(H1N1) virus underscores the importance of the ability to manufacture pandemic influenza vaccines in real time. Public health officials have concern that if the outbreak spreads to developing countries, governments may not have sufficient resources to respond. Past experience shows that high-resource countries may experience mild disease from influenza, but more severe disease may occur, with higher mortality, in developing countries. New, affordable vaccines are urgently needed to protect developing-country populations and strengthen worldwide efforts to contain an outbreak.
The rapid development, production, and distribution of pandemic influenza vaccines could potentially save millions of lives during an influenza pandemic. The current influenza vaccines are difficult to produce quickly and in large quantities, in part because most are made from embryonated chicken eggs. If an avian influenza strain is the cause of the next pandemic, the reduced availability of chicken eggs could further challenge the production of adequate supplies of vaccine.
Innovative, alternative vaccine strategies are needed that could produce much greater quantities of vaccine at a price that is affordable to the global population. PATH is collaborating with public- and private-sector partners to advance the development of promising new vaccines, focusing on novel technologies that could more easily be used in case of an influenza pandemic.
To expand the options for vaccine production, PATH is pursuing live attenuated (egg-based or cell-based) technology and recombinant technologies (proteins and virus-like particles), which could provide better “real-time” access and be produced more affordably, thereby increasing access for people living in low- and moderate-income countries. PATH is also exploring new adjuvants, vaccine ingredients that help boost the immune response, potentially allowing vaccine supplies to stretch further. While these new vaccine technologies will benefit real-time response in the future, this development will take time and we don’t have an immediate solution.
In addition to helping with pandemic preparedness, new vaccines could also address the high burden of annual or seasonal influenza, which is not well appreciated in many parts of the world. Increasing the affordability and availability of vaccines for annual influenza could yield substantial public health benefits.