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.

WFPI leaders, PCV trials

WFPI's involvement in the WHO-initiated PCV trials are led by Dr. Timothy Cain (Australia)


Prof. Lederman (Brazil) will be the Latin America representative in a project flowing from the WHO PCV trials, summarized below



Dr. Nasreen Mahomed, University of Witwatersrand, Johannesburg, South Africa, has been part of WHO's Radiology Working Group in the past and will join Prof. Lederman in the group newly convened for continuation of this project. 


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



 News since: 2015

 WHO Radiology Working Group: re-funded and re-launched

The WHO Radiology Working Group has been re-convened as the Chest X-Ray Global Advisory Group (see here). It forms part of the wider project to provide additional guidance and support for chest radiography in childhood pneumonia studies (above). The project is led by Kim Mulholland and Kate O’Brien. Funding is provided through a sub-grant from Johns Hopkins University as part of broader activities in PCV technical coordination supported by the Bill & Melinda Gates Foundation and with input from WHO. 

The WHO Radiology Working Group will take responsibility for key deliverables relating to the interpretation of chest x-rays. The primary outcomes are to develop a consensus on any clarifications to the definitions of the WHO methodology for the interpretation of pediatric chest radiographs (attached), to develop an updated library of chest x-rays with standardized interpretations, and to provide guidance on training methods for the use of the methodology.

The creation of this WHO Radiology Working Group is a continuation of previous efforts focused on improving the CXR endpoints for pneumonia studies. These include the original WHO Radiology Working Group formed in 1997 (which developed the standardized methodology), a 2011 radiology workshop in Hanoi that reviewed experience with this methodology, and a 2013 meeting on CXR endpoints in PCV impact studies in Geneva. The current WHO Radiology Working Group is seen as complimentary to these efforts, building on their recommendations and experience.

Prof Henrique Lederman (Brazil) and Dr. Nasreen Mahomed (South Africa) will be part of this Group and represent WFPI.

Specific involvement is required for a branch of the project run by the Murdoch Children’s Research Institute in Melbourne (MCRI), supported by WHO. The MCRI is a campus partner with the Royal Children’s Hospital and the University of Melbourne. Prof. Henrique Lederman (Brazil) will participate in a 2 ½ day meeting sometime in the first quarter of 2016 in Geneva to this end.

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