Conflict as final barrier to polio eradication

Poliomyelitis, a disease caused by poliovirus (types A, B, C) of the Picornaviridae virus family, is still endemic to three countries in the world: Afghanistan, Pakistan and Nigeria. Incidence of poliomyelitis has been reduced by 99% since 1988, yet areas of the world with poor sanitation and violent conflict continue to struggle with eradication. Why? - Poliovirus is typically transferred by the faecal-oral route so poor sanitation increases the likelihood that poliovirus will be transmitted from one human to another. Also, conflict prevents healthcare workers from accessing, often vulnerable, populations in order to run vaccination programs.

Of particular concern to public health workers and polio eradication groups are countries experiencing high or rising levels of conflict, either at the local or national level. Violent conflict and a distrust of public health workers has continued to prevent full eradication of poliovirus in Afghanistan and Pakistan. In 2015, Nigeria was declared polio-free, yet this year, Nigeria was added back onto the polio endemic list by WHO due to the appearance of three wildtype poliovirus cases in the northeastern province of Borna. The three cases were discovered in areas that had just recently been cleared of Boko Haram militants. Now, public health workers blame Boko Haram, a group known to advocate against modern medicine, including vaccines, for preventing access to poliovirus vaccines among northern Nigerian populations. Similar concerns have arisen in regards to increasing violence in areas around the world, most notably in Syria. However, polio is no longer endemic in a number of other countries that were experiencing violent conflict during successful eradication (Cambodia, Colombia, the Philippines, Sri Lanka, etc.) meaning that eradication is possible even during intense periods of violence. Past strategies employed to address heightened risk for a polio outbreak include: emergency vaccination of freed populations or ceasefire negotiations for emergency vaccinations and refugee and internally displaced people camp vaccination programs. Find out more about these barriers here.

Carolyn Oliver

Sources:
1. http://polioeradication.org/
2. http://www.humanosphere.org/global-health/2016/09/conflict-zones-pose-final-threat-eradicating-polio/
3. PolioNow Interactive Map: http://polioeradication.org/polio-today/polio-now/
4. https://www.ncbi.nlm.nih.gov/pubmed/10812729