Authors warn that the weaponisation of health care in Syria - a strategy of using people's need for health care against them by violently denying access - sets a dangerous precedent that the global health community must urgently address.

Marking six years since the start of the Syrian conflict (15 March), a study in The Lancet provides new estimates for the number of medical personnel killed: 814 from March 2011 to February 2017. With nearly 200 attacks on health facilities in 2016 alone, medicine denied in besieged areas, and indispensable young medics forced to deliver care in extreme conditions, the study describes the extent to which health has been weaponised in the conflict, in what human rights organisations have described as a war-crime strategy.

The study brings together data from multiple sources to analyse the impact of the crisis on health workers. It is the first report by The Lancet Commission on Syria led by the Faculty of Health Sciences, American University of Beirut (AUB).

The weaponisation of health care, a strategy largely used by the Syrian government and its main ally Russia, threatens the foundation of medical neutrality as laid out in international humanitarian law. The authors say the conflict has revealed serious shortcomings of global governance and call for a new role for global health organisations in responding to health needs in conflicts. This includes systematic documentation of attacks on health workers and their perpetrators via WHO, greater protection for health workers by strengthening the procedural mechanisms behind the UN Security Council Resolution 2286 condemning attacks on health workers, and greater accountability for breaches of international law.

"2016 marked the most dangerous year to date for health workers in Syria, and attacks on health workers continue. Rampant violations of international humanitarian law, and particularly the systematic attacks on health facilities and workers with intention to shut down care, to control the population set dangerous precedents." says Dr Samer Jabbour, one of the lead authors of the study, co-Chair of the Commission, and Associate Professor of Public Health Practice at AUB's Faculty of Health Sciences.

"The international community has left these violations of international humanitarian and human rights law largely unanswered, despite their enormous consequences. There have been repudiated denunciations, but little action on bringing the perpetrators to justice. This inadequate response challenges the foundation of medical neutrality needed to sustain the operations of global health and protect health workers in situations of armed conflict."

In 2012, the Syrian government passed a law effectively criminalising medical aid to the opposition, despite the explicit protections for health workers afforded by International Humanitarian Law. Attacks on health workers have included executions, imprisonment, abduction and torture.

Bringing together data from multiple sources, the authors report new estimates for the number of medical personnel killed in the conflict - estimated at 814 between March 2011 and February 2017. "We know that this number is a gross underestimate of medical personnel killed, limited by difficulties of evidence gathering and corroboration in conflict," says Dr Jabbour.

The authors also update estimates on the numbers of attacks on health facilities, 199 in 2016 (an increase from 91 in 2012), with the Syrian government and its allies, including Russia, responsible for at least 94% of attacks.

A feature of weaponisation has been repeated targeting of facilities to shut them down. Kafr Zita Cave Hospital in Hama has been bombed 33 times since 2014, including 6 times to date in 2017. M10, an underground hospital in eastern Aleppo, was attacked 19 times in 3 years and completely destroyed in October 2016.

"Over time, targeting has become more frequent, more obvious, and more geographically widespread. To the best of our knowledge, this level of targeting health facilities has not occurred in any previous war, and the data we were able to collect overwhelmingly show intent to target, which falls under the definition of a war crime," says Dr Jabbour.

Estimates suggest that between 2011 and 2015, at least 15000 doctors, or half of the pre-war numbers, had left the country. In Eastern Aleppo, approximately 1 doctor remained for every 7000 residents, compared with 1 in 800 in 2010. The only population survey conducted during the war estimated that two thirds of the population live in areas where health workers are insufficient or entirely lacking. The majority of areas without health workers were under military siege.

The exodus of older, more experienced doctors has left critical gaps. Younger, less experienced medics - many of whom are students - have become indispensable. They are left to fill gaps, often with no experience in trauma management or emergency medicine, and forced to interrupt their training. Not only does this mean increased risk for patients, but also warns of a serious shortage of skilled medical doctors in years to come.

In non-government controlled areas, the few health workers left face massive numbers of trauma victims, shortages of medicines, epidemics of infectious disease and chemical attacks. In areas under siege, surgical supplies and essential medicines are rarely allowed in, patients rarely evacuated, and public health measures such as water chlorination and measles vaccination blocked.

The bulk of Syria's remaining health workers are in government-controlled areas where they also face mortar attacks from rebel areas, heightened security risks, limitations on travel, and reduced training opportunities. Some health workers report being forced to breach ethical principles under pressure.

The study also highlights the resilience and resourcefulness of health workers who have mobilised on an unprecedented scale in response to the Syrian war - providing care under extreme conditions, creating networks to provide aid, organizing training and medical education, and gaining a political platform for advocacy and international support.

The report sets out a list of actions for policy makers. Although WHO has begun monitoring attacks, the tools implemented report only on the attacks, not the perpetrators responsible, undermining accountability efforts. The authors call on WHO and other UN agencies, the UN Security Council and UN General Assembly to review and strengthen their policies and practices, in terms of reporting breaches of medical neutrality, maintaining independence, resisting pressure by governments to follow the official line, providing undeterred advocacy for health workers under duress including in non-government controlled areas, and strengthening operational capacity to deliver health aid and support to health workers across conflict lines.

They also call for global solidarity for health workers in conflict, including the need for training and support, greater awareness on the global political agenda, and stronger donor attention.

The paper is published alongside a Comment from WHO and an Editorial in The Lancet, which states: "By their own definition, WHO's commitment to meeting the health needs of Syrians has been inadequate. The summits and intergovernmental meetings organised in the face of Ebola have not been matched by a response to this very different human catastrophe. If the USA is withdrawing from its role as a champion for a peaceful and democratic Syria, it is even more important that multi-lateral organisations step in to fill the vacuum and show leadership. WHO must now focus every effort on supporting the health structure and health workers in Syria, raising the finances needed to meet this challenge, and mobilising international support to resolve the humanitarian crisis in Syria, as they acknowledge in a Comment."

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