Polio update on country situations: Nigeria and the Lake Chad countries

March 2018

Overall: Nigeria and countries across the Lake Chad basin region (Niger, Cameroon, the Central African Republic and Chad), have implemented a strong response following the detection of four wild poliovirus (WPV1) cases in August 2016, after more than two years without detection. This response includes intensified vaccination campaigns to reach tens of millions of children across the Lake Chad region, and steps to improve and strengthen disease surveillance. At the same time, there is a need to maintain strong political leadership and coordination, continue improving the sensitivity of virus surveillance and implement new approaches to reach inaccessible communities.


  • Thanks to a rapid response to the detection of cases, it appears Nigeria and its neighbours have been able to prevent further spread of the disease. Although challenges remain – including gaps in surveillance and upwards of 200,000 children under 5 who are still inaccessible to vaccination teams in parts of Borno state and the Lake Chad islands – it has been over one and half years since the last case of WPV1 was detected in Nigeria. Additionally, there have not been any other reports of wild poliovirus in the rest of Africa for more than three years. 
  • Nigeria is working with other countries in the Lake Chad basin region (Niger, Cameroon, the Central African Republic and Chad) to ensure effective cross-border coordination, to vaccinate populations on the move and in border settlements, to explore areas with missed children and to synchronize major activities such as supplementary immunization campaigns (SIAs).
  • Nigeria’s acute flaccid paralysis (AFP) surveillance system benefits from community-based communication structures, including volunteer community mobilizers, the use of smartphones by health workers and volunteers to identify and report cases of paralysis, and new innovations to collect environmental samples from sewage water – all of which improve surveillance sensitivity and timely detection of AFP cases and polioviruses.
  • Religious and traditional leaders have been sensitized to help reach every last child.
    • Through the Northern Traditional Leaders Council on Immunization and Primary Health Care, traditional and religious leaders continue to play a key role in supporting polio eradication initiatives in high-risk states. 
    • 43/50 Emirs and 825/1027 District Heads supported the April 2017 polio campaign. 96% of the April pre-campaign meetings were chaired by Emirs, while District Heads chaired the pre-meetings at their LGAs. They hosted more than 1,000 community dialogues in 10 high-risk states. Traditional leaders also resolved 41% of the total reported non-compliance during the campaign.
  • In Cameroon, community participation has been used to promote upcoming vaccination campaigns, including through women’s associations and community radio stations.
  • In Chad, the priority districts have developed evidence-based communication plans, helping to guide communication activities to support the polio outbreak response.
  • Training and innovation has helped to expand immunization coverage in the region. For instance, in Niger, immunization coordinators and data managers have been trained in GIS mapping, subsequently using their new skills to collect data on the locations of villages in priority districts.
  • During 2017, the AFP surveillance network has been expanded in Lake Chad, through the introduction of the AVADAR project, driven by the Bill & Melinda Gates Foundation and WHO, which allows users to easily report cases of acute flaccid paralysis in health facilities and local communities using mobile phones. 


  • Ongoing conflict in the north-east region of Nigeria prevents vaccinators from reaching up to 232,000 children under age five, posing a risk of continued low-level transmission. Health workers are taking extraordinary steps to access some of these areas with vaccines. 
  • High population movement means that it can be very difficult to ensure that every child is reached. In some places, there remain significant gaps in population immunity. The programme uses multiple strategies and supports cross border collaboration between the Lake Chad countries to try and reach every last child.
  • There are hundreds of islands within Lake Chad that are not accessible or poorly visited by health workers from all countries in the sub-region. Focused efforts are underway to reach these locations with vaccines as a priority for all national programs in the area.  
  • Due to subnational surveillance gaps in some parts of Borno state, undetected circulation of poliovirus cannot be ruled out at this time.

Addressing the risks

  • The Government of Nigeria continues to demonstrate strong leadership and political commitment to reaching all children with essential vaccines, including polio vaccines.
    • The Nigerian government declared the detection of polio cases a national health emergency and the Executive Director of the National Primary Health Care Development Agency holds regular briefings with the National and State Emergency Operations Centers.
    • The Nigerian government has also declared a state of national emergency on routine immunization and established a National Routine Immunization Emergency Coordination Center (NRIECC). These efforts aim to fill immunity gaps for all vaccine preventable diseases, including polio, and help mitigate the risk of vaccine-derived polio viruses. 
  • Broad regional outbreak response is continuing to identify and vaccinate missed children and close immunity gaps. It is particularly important to raise childhood immunity to poliovirus in populations that have only recently become accessible by focusing on children arriving from security compromised areas in camps for internally displaced persons. 
    • In June 2017, joint missions conducted with Chad helped reach inaccessible islands within the geographical boundaries of Nigeria. 
    • Synchronized supplementary immunization campaigns between all countries in the Lake Chad region took place in October and November 2017, and in March 2018.
  • Innovative strategies have improved Nigeria’s ability to reach children in high-risk areas, including opportunistic campaigns whenever security permits, vaccination at markets and cross-border points, and outreach to nomads.
    • Permanent Transit Points target children in insecure areas and camps for internally displaced people. These children—who have often had no vaccination contact for years— receive an initial polio vaccination, and have their information recorded. Health workers then follow up to make sure the children receive all recommended doses. 
    • Two special interventions are also being conducted: Reaching Every Settlement (RES) and Reaching Inaccessible Children (RIC), which involve special strategies to reach children in insecure areas.
    • Children are being immunized at naming ceremonies across northern states in efforts to reach every child.
  • Nigeria is taking concrete steps to improve virus surveillance by using mapping technologies to address blind spots and testing the stools of healthy children arriving from inaccessible areas for poliovirus. 
  • Outbreak response assessments (OBRAs) of the Lake Chad Basin countries were held in November 2017, and resulted in a clear evaluation of the individual country programmes, alongside key recommendations, observations, and ways to improve response. 
    • This information was given to the countries, who will develop an individual plan of action to help ensure that the outbreak comes to a close. 
  • As more of the Lake Chad islands become accessible, the programme is working with national governments to provide vaccine to newly reached children, and set up surveillance. 
  • Volunteer Community Mobilizers are not only helping to eliminate polio, but are also increasing trust and impacting the overall health of their communities by working between campaigns to facilitate antenatal care, birth registration and routine immunization, and by providing messaging on handwashing, exclusive breastfeeding and the prevention and treatment of diarrhea.