The GAVI Alliance (formerly the Global Alliance for Vaccines and Immunizations), an organization that aligns public and private resources to ensure global vaccine access,  has made funding available through 2015 for PVC-7 in the 72 countries with the lowest per capita income (less than $1,000 per year).[35] In addition, countries and private donors have offered an advanced market commitment of $1.5 billion for 7 to 10 years to vaccine manufacturers, guaranteeing them a viable market for next-generation pneumococcal vaccines and simultaneously ensuring that GAVI-eligible countries can purchase these vaccines for a low price (currently less than $0.30 per dose).[35] Despite these actions, none of the GAVI-eligible countries had implemented the vaccine as of August 2008. More encouragingly, 11 have applied for GAVI funding and 8 of these applications (Central African Republic, Democratic Republic of Congo, Gambia, Guyana, Honduras, Kenya, Nicaragua, and Rwanda) have been approved, suggesting that many of these countries may introduce universal childhood pneumococcal vaccination soon.

PCV-7 also poses logistical challenges for low-income countries that decide to implement vaccination programs. Most vaccines are supplied in multidose vials that minimize volume and reduce medical waste but that must be transported and stored cold. Unfortunately, PCV-7 is currently available only in single-dose, prefilled glass syringes, which leads to increased transport and storage requirements and larger waste disposal. Pneumococcal vaccine only comes in prefilled, single-dose syringes that are not automatically disabled, raising safety concerns associated with the potential reuse of syringes and needles.[39] Satisfactory solutions to these problems must be developed for pneumococcal vaccine programs to be safe and effective.

In addition to the challenges of expanding vaccination to the developing world, limitations of the current vaccine strategy are already becoming apparent. Widespread pneumococcal vaccination with the PCV-7 vaccine in the United States has led to the increase in disease from serotypes not covered by the vaccine.[40] Particularly worrisome is the emergence of serotype 19A, which causes a virulent otitis media and is resistant to all Food and Drug Administration (FDA)-approved antibiotics for childhood ear infections.[41]  To temporarily address this problem, expanded 11- and 13-serotype vaccines, which include the predominant “replacement” serotypes, are in trials and are expected to become available for use. Constant surveillance will be required, however, as every new vaccine will further alter the prominent serotypes in the environment. Ultimately, a pnuemococcal vaccine that is not serotype-specific would be the ideal solution, and several of these “common-antigen” vaccines are currently in development.

Overcoming the challenges to global introduction of the pneumococcal vaccine and working to develop even more effective next-generation vaccines remain urgent public health priorities for the WHO and UNICEF (United Nations Children’s Fund).[19] Successful implementation is imperative, as the global use of pneumococcal conjugate vaccine will prevent an estimated 5.4 to 7.7 million childhood deaths by 2030.[35]

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Tony Rosen, MPH, MD
Tony Rosen, Division of Geriatric Medicine and Gerontology, Weill Cornell Medical College, Cornell University, New York, New York;

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2. US Centers for Disease Control and Prevention. Ten great public health achievements in the twentieth century, 1900-1999.
3.   Parker AA. Implications of a 2005 measles outbreak in Indiana for sustained elimination of measles in the United States. New Engl J Med. 2006;355:1184.
4. Okonek BAM, Peters PM. Vaccines: how and why
5. Baxby D. Vaccination: Jenner’s Legacy. Berkeley, UK: Jenner Educational Trust; 1994. 6. Parish HJ. A History of Immunization. Edinburgh, UK: Livingstone; 1965.
6. Gross CP, Sepkowitz K. The myth of the medical breakthrough: smallpox, vaccination, and Jenner reconsidered. Int J Infect Dis. 1998;3:54-60.
7. Salmon DA,  et al.  Compulsory vaccination and conscientious or philosophical exemptions: past, present, and future. Lancet. 2006;367(9508):436-442.

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