By Sophie Désoulières, senior South Asia analyst, and Samina Ahmed, South Asia project director at International Crisis Group.

As the world marks Polio Day today, Pakistan remains the greatest impediment to a polio-free world.

The country has more polio cases than any other, reflecting a double policy failure: to prioritise the health of its citizens, and to curb violent extremism. Pakistan's deadly conflicts increase the likelihood the disease could spread to other countries.

Some progress has been made. The number of infections has dropped sharply this year, with 38 cases reported by Pakistan as of 14 October. This decline in infections — in June, the BBC reported a 70% drop — is largely the result of more innovative ways of expanding vaccination coverage, including more involvement by communities in eradication efforts. These initiatives came after Islamabad was jolted into action by shocking figures last year, when 328 Pakistani children were paralysed by polio, 300 more than in 2005.

The decline in polio cases can also be partly attributed to improved planning, coordination and communication. The eradication program's emphasis on community buy-in is paying dividends, as is the shift from an over-reliance on the police and other security agencies to convince communities to protect and provide polio workers.

But Pakistan is still one of the few remaining countries where polio is endemic, and the risk of a spike in infections will not go away unless there is an overhaul of the dysfunctional public health system. Even this may not be enough. Hardline Islamists have convinced many families that vaccination is un-Islamic, a health risk and a Western ploy to harm children. So far efforts to persuade Islamist leaders and local mullahs to stop misleading families with anti-immunisation propaganda have yielded mixed results.

Violent extremism, conflict and instability mark most polio 'reservoir' areas, where the virus thrives. These include the sprawling port city of Karachi, Khyber Pakhtunkhwa and Balochistan's provincial capitals and outlying districts, and the Federally Administered Tribal Areas (FATA) bordering on Afghanistan.

The dangers of backsliding have been clearly illustrated in FATA. In mid 2012, Pakistan and its Global Polio Eradication Initiative (GPEI) partners were hopeful the region's fight against polio was being won. Then Pakistani Taliban groups in FATA's North and South Waziristan agencies imposed an arbitrary ban on polio vaccination.

The Pakistani Taliban commanders in North Waziristan and South Waziristan, both signatories of peace deals with the military, said the polio immunisation campaign was a Western cover to identify and target militants. As proof, the Islamists pointed to a May 2011 hepatitis B vaccination drive organised by the CIA to help confirm the presence of Osama bin Laden in Abbottabad.

Subsequent extremist attacks against polio workers (particularly women), and the police protecting them, have resulted in 80 deaths since July 2012. The hundreds of children who contracted polio are partly casualties of this violence, which has played a major role in hampering the state's ability to eradicate the disease. Paradoxically, it was increased vaccination cover of populations fleeing the violence that contributed to the recent reduction in cases.

It is clear recent advances made in the battle with polio will remain fragile while the militant networks are intact. If a lower polio infection rate is to be maintained, countering anti-immunisation propaganda will be essential. This requires building on initiatives to engage communities, to win their trust and enable essential services, particularly more pervasive immunisation and significantly improved public health and sanitation.

Cooperation with, and granting complete access to, non-government organisations and civil society groups, including in conflict zones, is also vital if all children are to be protected. The head of an NGO that works in FATA's bordering districts told Crisis Group: 'If we were given the (polio) drops, it would be so easy for us to ensure that every child is immunised since we already work in these communities'.

Pakistan and its international partners cannot afford to be complacent. The key test will come in May, when temperatures rise again and the low-transmission season ends. It will then be possible to judge if every child has indeed been reached, and whether Pakistan is truly progressing towards ending the country's endemic polio status and averting a global health risk.

Photo by Rana Sajid Hussain/Pacific Press/LightRocket via Getty Images