Polio outbreak in Sudan successfully stopped and declared closed

Sudanese refugee children receive polio vaccination at hospital in the Kounoungo refugee camp in the north east of Chad. Sudanese refugee children receive polio vaccination at an IMC (International Medical Corps) hospital in the Kounoungo refugee camp in the north east of Chad near the Sudan border, August 31, 2004. About 11,500 refugees are sheltering in the Kounoungo refugee camp. Aid agencies have set up camps in this remote, impoverished corner of Africa to provide medical care and food in what officials call one of the world's worst humanitarian disasters. REUTERS/Luc Gnago - RTR9N4J

Sudan’s outbreak of circulating vaccine-derived poliovirus type 2 (cVDPV2) has been successfully stopped, according to experts from WHO, UNICEF and U.S. Centers for Disease Control and Prevention.

Declared in 15 out of 18 states, the outbreak was caused by a circulating vaccine-derived poliovirus (cVDPV2) strain imported from Chad, paralyzing 58 children.

The announcement came after virtual and in-country reviews of Sudan’s response to the outbreak and its surveillance system by a team of experts in polio eradication, global public health, epidemiology, and vaccine management.

The final Outbreak Response Assessment, held between July 24 and August 1, included interviews and reviews of reports and records with surveillance and immunization staff at state, locality, and health facility levels.

The findings of the Outbreak Response Assessment, coupled with the absence of the cVDPV2 virus for more than 18 months in the presence of sustained high-quality poliovirus surveillance, make it possible to conclude that the cVDPV2 outbreak can now be declared closed.

“The closure of this outbreak speaks to the skill and diligence of health workers and public health officials in Sudan, and to the extraordinary commitment of the Government of Sudan demonstrated by allocation of significant domestic financial resources to the response, during one of the most challenging periods of the COVID-19 pandemic,” said Dr Ahmed Al-Mandhari, WHO Regional Director for the Eastern Mediterranean.

Backed by UNICEF and WHO, the Federal Ministry of Health successfully organized two nationwide vaccination campaigns targeting children under-5 years of age to contain the spread of poliovirus, reaching over 95% of the target population.

Community engagement and social mobilization efforts were stepped up to ensure information about the dangers of the disease and the need to immunize every eligible child reached every household.

“Two nationwide campaigns using monovalent oral polio vaccine type 2 (mOPV2) covered all 18 states in November 2020 and January 2021, reaching over 8 million children under 5 in each of the 2 rounds. In every location, vaccinators took precautions against COVID-19, including using hand sanitizer and wearing masks. Despite the closure of the outbreak, the country remains vigilant for possible poliovirus importation,” said Dr Nima Saeed Abid, WHO Representative in Sudan.

“The closure of the polio outbreak is a remarkable achievement for the children of Sudan. Community engagement has been at the heart of efforts to turn vaccines into vaccinations for over 8 million children. This success is a testament to the commitment of health workers, especially women, who continue to work selflessly and passionately to deliver vaccines,” said Mandeep O’Brien, UNICEF Representative in Sudan.

Across the Eastern Mediterranean Region, cVDPV2 cases have increased in recent years, and the movement of people across borders underscores the risk of importation across and beyond the Region.

The cVDPV2 strain that led to 58 cases in Sudan has been detected in 8 neighboring countries before and after Sudan’s outbreak.