GENEVA, Switzerland — Polio has existed as long as human civilization.
It terrified parents because children were especially susceptible to the incurable disease, which caused paralysis and in some cases death.
Only 60 years ago, the United States experienced an epidemic, with nearly 58,000 cases reported in 1952. More than 3,000 died of polio that year.
Still, as of 2012 polio was eliminated in a majority of the world thanks to global initiatives to vaccinate children.
It only remained endemic in three countries: Pakistan, Afghanistan and Nigeria.
However, the chaos of war and breakdown of infrastructure have allowed polio to return to places like Syria and Somalia.
Until last month, Syria had not seen a single case of polio since 1999.
However, the risk of an outbreak grew as the rate of children vaccinated against the highly contagious disease dropped from 90 percent in 2010 to around 68 percent now, according to the World Health Organization (WHO).
In October, 10 cases of polio were confirmed in Syrian children — the first in a decade. Another 12 cases remain under investigation.
Polio also surfaced recently in the Horn of Africa.
The WHO's Global Polio Eradication Initiative (GPEI) has confirmed 175 cases in Somalia since April — the first cases in the country since 2007.
Kenya reported 14 cases of polio and Ethiopia another four.
The persistence of the disease in impoverished and conflict-torn areas has hurt efforts to eradicate it, but public health experts say that the response has been massive and positive.
The Polio Eradication Initiative is at work on the ground in Syria and neighboring countries, working alongside local health workers to vaccinate millions of children under five, to ensure the disease doesn't spread along the lines of refugee populations across the region.
This week, the Syrian government pledged to ensure the delivery of vaccinations across the country and help vital medicines reach areas that are currently contested.
To get a sense for the latest outbreaks and what they mean, GlobalPost spoke with three experts: Walt Orenstein (WO), a vaccine expert at Emory University, Oliver Rosenbauer (OR), spokesperson for the Global Polio Eradication Initiative at WHO and Simon Ingram (SI), senior spokesperson for UNICEF in the Middle East and North Africa.
What are the factors that led to the recent reported outbreak of polio in Syria?
SI: The polio outbreak is one critical consequence of the terrible damage that more than two and a half years of conflict have done to Syria's public health system. Across the country, hospitals and health centers have been destroyed or abandoned, and vital services — such as routine immunizations vital for children's health have been reduced or discontinued.
This is particularly true in areas such as Deir Ezzour — where the polio cases have been confirmed — which have witnessed particularly intense fighting. It is very likely that more cases will turn up there, because of the large number of children whose immunity against polio — which is built up over time by repeated doses of oral vaccine — is not as strong as it should be.
We have appealed to all sides in the conflict to facilitate their work and thus far some 60,000 children in Deir Ezzour have already received polio drops. We hope that many more will receive them in the coming days.
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How much have the outbreaks of polio in Somalia (spring 2013) and now Syria set back eradication efforts?
SI: Given that the world has been on the brink of eradicating polio, it is of course extremely sad that we are now seeing this terrible disease resurface again in this region. For Syria, which had no cases of polio since 1999, it is definitely a serious blow, and there is of course a real risk that the disease will spread further, inside the country and beyond, into the broader region.
However, the efforts to counter the outbreak and prevent its spread now being deployed by the governments in the region with the support of WHO and UNICEF have also been impressive. Inside Syria, a vaccination campaign led by the Ministry of Health began on Oct. 20 targeting 1.6 million children under five years of age against polio. This campaign will continue for two weeks.
WO: All of the current outbreaks originate from viruses coming from the three endemic countries — Afghanistan, Pakistan and Nigeria. These countries, which have never terminated polio transmission, serve as reservoirs from which the virus can be transmitted to other countries when infected persons travel across borders.
However, the good news is that this year, cases in those countries have decreased by more than 35 percent compared to this time last year, suggesting real progress in breaking the chains of human-to-human transmission. The problem is that so long as poliovirus transmission continues in these endemic countries, we have a risk of outbreaks in other countries where there are populations susceptible to polio.
What are the risks of it spreading, especially with the flow of refugees from Syria across the Middle East?
WO: The risk is high, because polio is extremely contagious, and because of the population movements and pockets of unimmunized children in the area. Syria and six neighboring countries are planning a synchronized, multi-country response, which is really unprecedented cooperation, but it’ll be critical for vaccinators to have unhindered access to children in Syria. To me, the biggest takeaway from this tragic situation is that we urgently need to end polio in the endemic countries to prevent this from happening again.
OR: An outbreak response means you go in to the infected areas and start to immunize kids straight away. Afterward, you begin the larger response throughout the country and in neighboring countries like western Iraq, Jordan, Lebanon and southern Turkey.
For the next six to nine months, we are running monthly campaigns to boost immunity levels as rapidly as possible. That’s the plan now being put in place. Nobody is saying this is Syria’s problem and that doesn’t affect us — other areas can easily become re-infected.
How do polio workers deal with the safety and security issues in countries like Syria and Pakistan (where polio workers have been targeted by militants) when administering vaccines?
OR: It’s difficult for sure. The health workers are local volunteers but it’s an orally administered vaccine so you don't need to be a trained healthcare worker. The person who comes to your door to vaccinate your children lives one street over from you, so to speak.
In Syria, the key will be to coordinate with all the humanitarian actors on the ground, including the government. The Syrian government was the first to announce they had a polio outbreak and the first to launch a campaign to vaccinate against measles, mumps, rubella and polio. The approach to rebel-held territory is still being mapped out.
WO: This isn’t the first time the GPEI has had to confront issues of security, having eliminated polio successfully even in times of outright war. So we know polio can be rooted out even in the most complex situations — we just need the commitment and collaboration on the ground to make it happen. The recent commitment of the Syrian government to grant access to all children is a promising first step.