Background

In 2000, about 14.5 million cases of serious pneumococcal disease were estimated to occur among children under 5y and about 820 000 childhood deaths due to pneumococcal disease, 90% attributable to pneumonia, may have occurred (O'Brien et al., 2009). Cases and deaths are concentrated in Sub-Saharan Africa and South and Southeast Asia.


Pneumococcal conjugate vaccines (PCV), which enhance immunogenicity through conjugation of capsular polysaccharides to diphtheria toxoid protein, were developed in the 1990s, and the first of these was introduced in the USA in 2000, then progressively in other industrialised and emerging economy countries. Various higher-valency vaccines have since been developed to address the insufficient serotype coverage in industrialised countries and highly limited coverage in developing and high-burden countries.

In 2007, the World Health Organization (WHO) recommended global expansion of PCV vaccination, with priority introduction in “countries where mortality among children aged <5 years is >50/1000 live births or where >50 000 children die annually" (WHO, 2007). PCV implementation in developing countries, mainly financed through the Global Alliance for Vaccines and Immunisation (GAVI) and Advance Market Commitment mechanisms, is expected to roll out over the next decade.
PCV may be the single most important new vaccine in terms of preventable global disease burden. While the introduction of PCV poses immense challenges in most developing countries (obstacles to delivery include by poverty, weak health systems, lack of human resources and infrastructure and the geographical remoteness of target populations), specific vulnerable populations deserve special attention and stand to potentially benefit disproportionately from PCV vaccination.

WHO PCV Studies: A consensus method for reading chest readiographs

 

  

 

WHO meeting Sept '13: future radiological needs for establishing Endpoint Pneumonia during trials

 

presented its mission & work during this meeting as part of a potential drive to improve image quality and reader consistency

     

Background literature

World Health Organization Pneumonia Vaccine Trial Investigators’ Group report on Standardization of interpretation of chest radiographs for the diagnosis of pneumonia in children: click here

World Health Organisation definition of “radiologically-confirmed pneumonia” may under-estimate the true public health value of conjugate pneumococcal vaccines, Shabir A. Madhi, Keith P. Klugman,ScienceDirect 2006: click here

Standardized interpretation of paediatric chest radiographs for the diagnosis of pneumonia in epidemiological studies, Thomas Cherian, E. Kim Mulholland, John B. Carlin, Harald Ostensen, Ruhul Amin, Margaret de Camp, David Greenberg, Rosanna Lagos, Marilla Lucero, Shabir A. Madhi, Katherine L. O'Brien, Steven Obaro, Marc C. Steinhoff & the WHO Radiology Working Group, 2005: click here