In the weeks since mid-June, when the jihadist group known as the Islamic State of Iraq and Greater Syria (ISIS) obliterated the border between Syria and Iraq and then swept across much of northern Iraq, the extent to which the Syrian conflict has engulfed the region has become increasingly clear. But jihadism is not the war’s only wider threat. For medical workers in the Middle East, it has long been apparent that the catastrophic health effects of Syria’s crisis were spilling over into neighboring countries.

With several million Syrian refugees now living in Lebanon, Jordan, Turkey, and Iraq, and millions more displaced inside Syria living in dreadful conditions, the threat of epidemics spreading from Syria to surrounding countries has grown with frightening speed. Among the diseases that have spread most rapidly are measles, hepatitis, and leishmaniasis. Then there is polio, a terrifying disease of early childhood that had long been eradicated in the Middle East. In Syria, it was eliminated in 1995, yet since mid-2013 the country has faced an outbreak of polio that has spread widely across opposition-controlled areas of the north. And now polio, like the jihadists, has spilled across the border to Iraq, crippling a baby boy in February and a young girl in April, both in Baghdad.

Far from a natural tragedy, this public health crisis is largely a result of the Syrian government’s years of attacks on the medical system in opposition-held parts of the country, with its barrel-bomb and occasional chemical attacks, as well as its withholding of basic public-health measures such as vaccination and safe water. But as I have documented in The New York Review, the spread of polio has been aggravated by the inadequate response of the World Health Organization (WHO) and UNICEF—the two UN agencies responsible for dealing with the epidemic. And new revelations have made clear that independent polio vaccination efforts in northern Syria have been severely hampered by those agencies’ mismanagement.

Over the past year, ISIS has made this situation even worse with its kidnapping of international health workers, detention and intermittent execution of national medical personnel, and seizure of aid convoys. Dr. Wasim, a Shi’a doctor who had left southern Damascus in late March after three years of working in the conflict, told me that he had been one of only nine doctors serving a population of more than 150,000. Having been detained several times by both government forces and extremist Islamist groups, he was ultimately forced to flee:

In February, some of my patients from an extremist group told me, “Doctor you saved our lives. So we need to tell you that now we are looking for you. So get lost. Now. Because you won’t survive like the last time.” So I had no choice but to go out of the besieged area. Because my only other choice was death.

In late June, several doctors from Deir Ezzor, where the radical group has taken control, told me there is no longer any trauma service, operating capacity, or emergency room in the city. Dr. Wazel, a surgeon from Deir Ezzor city, explained:

The only way out is across the Euphrates. Now that ISIS has snipers on the bridge, only critically ill civilians can be transferred out, and only by crossing in a rowboat. It’s very dangerous. There is no hope if you are an injured [Free Syrian Army] fighter—if ISIS finds you, you are finished. For the rest, first we have to check the river each morning to see if boats are moving. If they are, we may be able to negotiate to cross and get to the road on the other side. Then we row across—the patient, the oarsman, and two others to balance the boat and then carry the patient to the road and find a taxi. If ISIS catches us doctors at any time, we will be executed immediately.

Now there are finally signs that the world is waking up. On July 14, the UN Security Council passed a resolution authorizing cross-border humanitarian aid into rebel-held areas of Syria, even without government permission—a step that could finally allow UN agencies to assist polio vaccination efforts in the northern part of the country openly. This follows the WHO’s announcement in early May of a “fundamental shift” in its polio policy: after months of claiming that polio in Syria was under control, it declared a “Public Health Emergency of International Concern”—a declaration reaffirmed on July 31. According to the agency, the outbreaks of polio in Syria, Cameroon, and Pakistan and the spread to surrounding countries now constitute a global threat. WHO advised the three countries to declare national polio emergencies, vaccinate all residents, and document the vaccination with WHO-approved certificates.

Showing the severity of the polio crisis, this was only the second global emergency the UN agency has announced about any disease. (The first was the H1N1 flu in 2009; this month, WHO also declared an emergency for ebola.) Long overdue, WHO’s response is still disappointing. Consistent with its usual deference to national sovereignty, the agency also said that it is up to the countries in question to deal with the problem. “We’re saying to the Pakistanis, the Syrians, and the Cameroonians, ‘You’ve really got to get your acts together,’” a WHO spokesman told The New York Times.

For anyone familiar with Syria today, it is hard to imagine how a country torn by conflict and a brutal counterinsurgency strategy, and suffering one of the worst humanitarian disasters since World War II, might suddenly “get its act together.” Despite WHO’s demand in May that the Syrian government declare a national public health emergency, Damascus still has not done so. Nor has it ensured that all residents and long-term visitors planning international travel receive a dose of vaccine prior to departure.

Moreover, nearly all the cases of polio have occurred in areas of northern Syria under rebel control, where the government is seemingly doing everything in its power to prevent vaccination. The Syrian government has appealed to the UN for hundreds of medicines for areas of the country it controls, while largely ignoring the far more dire needs of opposition-held areas. Many children, especially newborns, still do not have access to polio immunization. Daily government airstrikes target the very health facilities that should be the foundation of vaccination efforts, as well as the children who should be protected from polio, measles, and other preventable childhood diseases. As Dr. Ammar, a doctor from Aleppo, said to me bitterly after an April 30 airstrike killed twenty-two schoolgirls, “The government’s polio control strategy for children is to kill them before they can get polio.”

Against all odds, a highly successful, independent polio vaccination effort has nonetheless proceeded in the north without any backing by the Syrian government. Called the Polio Control Task Force, this effort has been run by a coalition of Syrian groups operating from across the northern border in Turkey, led initially by the Syrian American Medical Society and organized by the humanitarian arm of the Syrian opposition in exile, known as the Assistance Coordination Unit (ACU), with the support of the Turkish Ministry of Health.

From the start, the task force suffered severe shortages of vaccine needed to reach the 1.5 million children in the region. The core of the problem was that WHO and UNICEF interpreted their mandates as preventing them from aiding such cross-border humanitarian efforts without the Syrian government’s consent, which Damascus refused to provide. It was not until the last days of 2013 that the task force managed to get its first vaccines through other channels. Despite these limitations and the severe shortage of doctors, the task force and its network of 8,000 health workers across northern Syria undertook a door-to-door campaign that successfully vaccinated more than 1.25 million children in each of the seven rounds conducted since January.

This was no easy feat. Polio vaccines must be kept refrigerated, and many parts of northern Syria lack regular electricity. Because multiple doses of vaccine are required to ensure protection from this crippling disease, each child had to be individually identified and repeatedly visited. Reaching these children required negotiating with the plethora of armed opposition groups controlling different areas, including ISIS. Several doctors and vaccinators were killed or injured in airstrikes, and considerable ingenuity was required to overcome other challenges presented by the Syrian military. As Dr. Jasem, a Syrian doctor working for the task force, explained to me in June:

In Hama, we had to smuggle the vaccines past checkpoints in canisters on the milk truck. Vaccinators started work at midnight, as government snipers tended to shoot at them during the day, from here [indicating a hill on my map]. It’s too dangerous to ink the children’s fingers, or mark the doorways [to indicate that they have been vaccinated]– the government would have killed them for disloyalty.

Remarkably, WHO and UNICEF now take credit for this campaign. In reality, in December, rather than supply vaccines directly to the Polio Task Force, WHO adopted the half-measure of acquiring one million doses of vaccine and giving them to three international humanitarian organizations for distribution in northern Syria: Doctors Without Borders–Holland, International Medical Corps, and Save the Children UK. The vaccine was of the bivalent variety, considerably more effective than the trivalent variety that, with the assistance of the Turkish government, was the best that the task force could acquire. However, unlike the Syrian groups behind the Polio Task Force, none of the international organizations had any capacity to mount their own vaccination campaign in northern Syria, so the vaccines sat in warehouses undistributed.

In late January, the Polio Task Force’s planned second round of vaccination faced further delay because of a lack of vaccines. At this time, WHO quietly advised the task force to seek access to the vaccines from the three international NGOs sitting on one million unused polio doses. International Medical Corps and Doctors Without Borders–Holland immediately agreed and their stocks of effective bivalent vaccine were shifted to Deir Ezzor and other eastern areas where the outbreak was worse. Save the Children UK, however, did not make their vaccines available and it was understood by the task force that Save’s one quarter million vaccine doses stored in Idlib had been destroyed. Three months later, in May, the task force learned that Save the Children was still in possession of the 250,000 doses. It again issued an urgent request for the vaccines.

In May, after lengthy exchanges between the local health manager of Save the Children, members of the Polio Task Force, and local WHO officials, Save the Children said it had the vaccines and agreed to provide them, but also said that its cold-storage had been compromised in January, when there was inconsistent electricity for twenty-six days and no back-up generator. Save the Children’s team insisted that the vaccines were still usable, but WHO officials, concerned about the vaccines’s viability after this poor storage, asked that photos of the vials be sent from Idlib. After reviewing the viability seals on the vials, Dr. Raul Bonifacio, a WHO official, concluded that “these vaccines cannot be used for any polio vaccination activity.”

Save the Children UK has now applied to the Gates Foundation for funding to lead vaccination activities for measles in Idlib governorate. And while local politics have been blamed for delaying a comprehensive anti-measles vaccination campaign, UNICEF, working under a shroud of secrecy, is replicating WHO’s ways by mistakenly acquiring measles-only vaccines for the Syrian opposition-led Measles Task Force while distributing to international NGOs the better measles-rubella vaccines that are needed for broad protection.

Missteps such as these, combined with the intensifying brutality of the Syrian military, may now be undermining polio eradication efforts across the Middle East and more widely. Only eighteen months ago, the WHO-led Global Polio Eradication Initiative (GPEI) could claim to be on the verge of wiping out the disease. After twenty-five years and a multi-billion dollar campaign, the number of countries with endemic polio had dropped from 125 to 3, and two out of the three wildpolio viruses have been eliminated. Yet polio is now flourishing in Central Asia and Africa, as well as in the Middle East. Since January 2013, more than 550 new cases of type 1 wildpolio have been reported in ten countries, and numbers rise weekly. The virus has been detected in the sewers of other countries that had previously eliminated polio, including Israel and Egypt. Already by June, the numbers of polio cases in Pakistan this year outstripped the total for all of 2013.

Type 1 virus is not only the most virulent—causing the most serious paralysis and the worst epidemics—but also has the highest ratio of paralytic to subclinical infection. Yet at the very press conference where the global polio emergency was announced, the director of WHO’s polio effort, Bruce Aylward, described the eradication program as “in an extremely good position, aside from this spread in the low season, and aside from the situation in Pakistan.” Since then, Equatorial Guinea has been added to the list of countries exporting the virus—its strain was discovered in the sewers of Brazil in June, the first known presence of the polio virus in that country in more than twenty years.

Part of why WHO is able to maintain an optimistic view of polio eradication efforts is that it significantly undercounts the incidence of polio. Ordinarily, diagnosis is straightforward: a child presents with acute onset of paralysis, and a laboratory confirms that poliovirus is present in the child’s stool. This is the sole definition used by WHO; for the agency, a case of “acute flaccid paralysis”—the clinical description of a suspected case of polio—does not count unless a laboratory has confirmed the presence of the virus in two stool samples taken within fourteen days of the onset of paralysis. But in a country like Syria that is riven by violent conflict, the timely collection of stool samples and their transport to the sole officially recognized laboratory across front lines in Damascus are often impossible.

Given the difficulty of laboratory testing in the midst of a war, WHO could have supplemented this standard for determining the presence of polio with a test that relies on clinical criteria. The website of the US Centers for Disease Control, which is generally considered to set the gold standard on public-health issues, describes such criteria: a “probable case” of polio can be diagnosed when there is “acute onset of a flaccid paralysis of one or more limbs…without other apparent cause,” and a “confirmed case” can then be established when the patient “still has a neurological deficit 60 days after onset of initial symptoms.” Expert Review Committees in Syria and in Turkey, at which WHO presides, use this definition, supplemented by the criterion that the case must emerge from an area where polio has been found. Indeed, WHO itself used such a clinical test before laboratory analysis became widely available, from 1988 through to 2002, the era when polio was eliminated from the Americas, Europe, the Middle East, and the Pacific regions. But in its 2005 International Health Regulations, WHO moved to exclusive use of laboratory testing for polio, explaining: “Poliomyelitis cannot be diagnosed reliably on clinical grounds because other conditions presenting with acute paralysis can mimic poliomyelitis.”

This adherence to an unattainable standard in war-torn Syria has led WHO to significantly underestimate the scope of the outbreak. WHO did not recognize the polio outbreak until October 29, 2013, while the first Syrian case of polio using a clinical test was actually diagnosed on May 23. Similarly, using exclusively its laboratory test, WHO found only twenty-five cases in 2013 and just one in 2014, while the ACU, combining laboratory and clinical testing, found forty-seven cases in 2013 and, despite worsening conditions in the devastated country making any diagnosis difficult, at least another four in 2014 across three governorates of Syria— Hama, Aleppo, and Deir Ezzor. Each one of these manifested cases of paralysis can mean up to one thousand infected carriers who do not show symptoms but can still spread the disease.

Of course laboratory verification, where possible, is the ideal, and particularly useful to conclusively determine the success of long-term eradication efforts in non-conflict situations. But it is utterly impractical amidst the chaos and destruction of northern Syria.

Needless to say, a child crippled by polio is still a child crippled by polio, whether or not a timely stool sample can be collected and sent to a national laboratory for confirmation. Identification of each polio case is also important because, contrary to popular belief, polio is treatable—with good care, more than 50 percent of acutely crippled children either recover completely or are left with only mild paralysis. But a polio diagnosis that excludes children whose stools cannot be lab-tested denies them effective therapy. That can mean the difference between substantial recovery and a lifetime of disability and stigma.

What Syria’s experience makes clear is that the polio crisis is not simply a result of conflict or war, as leading WHO and UNICEF officials claim. After all, polio has not recurred in such conflict-ridden countries as South Sudan, the Central African Republic, or the Democratic Republic of Congo. Polio did not even break out in Iraq during the eight years of war and turmoil following the US invasion of 2003. Yet it took only some two years of fighting in Syria for polio to reappear—and only another six months for it to spread to Iraq. Syria stands out as an epicenter of polio’s reemergence—after an eighteen-year absence—because of the extraordinary brutality of the government.

And polio is hardly the only disease of concern emanating from Syria. There are hundreds of cases of multidrug resistant tuberculosis on top of a measles epidemic. There are outbreaks of bloody diarrhea in Raqqa, hepatitis in Hasseke, typhoid in Hamas, and leishmaniasis across Aleppo and even the fatal version, visceral leishmaniasis, in Idlib. Malaria, unheard of in Syria, has recently been found in Lattakia. Many of these problems originated in years of governmental neglect and have been greatly aggravated by the military’s wartime atrocities.

When the government becomes the primary source of a public-health problem, as Syria is today for polio and a host of other threats to global health, it becomes a wholly inappropriate and unreliable partner for public-health efforts. Yet WHO and UNICEF, as UN agencies, have until now taken the position that it cannot act without the government’s consent, putting partnership with a brutal dictatorship over their responsibility to public health. It is too early to determine whether the new UN Security Council resolution will significantly change that calculation. But it shouldn’t require Security Council action for public-health officials to recognize that when government abuse is the cause of a public health crisis, WHO should either change its usual methodology of deferring to that government or bring in another organization without the same institutional constraints. The children and people of Syria—and the world—deserve no less.

Following the publication of this article, the NYRblog published an exchange between the author and a spokesman for Save the Children. The text of the article has been altered.