In a Comment published in The Lancet, Ala Alwan and Bruce Aylward from the World Health Organisation (WHO) respond to recent allegations that UN agencies including WHO have blocked vaccination campaigns and obstructed the testing of polio samples. Outlining the actions which have been taken by WHO and other agencies to address the rising threat of polio in the Middle East, Alwan and Aylward state that, "Fully implementing this response plan has required overcoming immense hurdles to reach every child amid the wreckage of Syria's public infrastructure and health system, the active conflict and insecurity, the dearth of trust, and one of the largest refugee crises since the second World War. These challenges have been compounded by erroneous allegations that - rather than doing everything possible to protect all Syrian children and the huge international investment in global polio eradication - United Nations agencies, and the World Health Organization (WHO) in particular, had 'blocked a vaccination campaign', were 'obstructing the testing of polio samples', and by extension disregarding fundamental humanitarian principles."

"Every day, thousands of local and international public health workers, community members and volunteers on all sides of this conflict risk their lives to deliver basic services - including and especially immunization - to all Syrians. It is essential that the complexities of the environment in which they are working is properly understood and that where information is incomplete, or is not shared for security reasons, it is not replaced with speculation or accusation...Halfway through the Syrian polio outbreak response, many critical programme indicators are improving, particularly in terms of access to vaccine, coverage and surveillance performance. Addressing the remaining gaps in programme implementation in Syria is a deadly serious issue; compounding this challenge with inaccurate information significantly and unnecessarily complicates an already very difficult and dangerous operating environment."