Conduct of vaccination in hard-to-reach areas to address potential polio reservoir areas, 2014–2015

The Global Vaccine Action Plan (GVAP) seeks to achieve the total realization of its vision, in which all individuals and communities enjoy the full benefit of immunization, through equitable access to immunization as well as utilizing the immunization systems for delivery of other primary healthcare programs [1]. The inequities in accessing hard-to-reach areas have very serious implications for the control and prevention of vaccine-preventable diseases, especially the polio eradication initiative. Hard-to reach is a term used to describe those subgroups of the population that may be difficult to reach or involve in public health programs, especially with regards to health and social inequalities [2‐4]. In this context, the project operationally defined hard-to-reach areas as geographically difficult terrain, with any of the following criteria: having inter-ward, inter-Local Government Area (LGA), or interstate borders, scattered households, a nomadic population, or a waterlogged/riverine area, with no easy access to healthcare facilities and insecurity.

Hard-to-reach areas serve as a niche for sustaining the transmission of diseases. Children in remote areas mostly have low immunization coverage, and this gap impacts child health [5]. The National Polio Eradication Emergency Plan (NPEEP) 2014 reported that, in Nigeria, over a third of cases of polio in 2013 were under-immunized and from the hard-to-reach settlements in the four polio-endemic states of Bauchi, Borno, Kano, and Yobe. The plan recommended targeting the hard-to-reach to improve population immunity and interrupt polio transmission as one of its strategic priorities for 2014 [6].

Reaching the hard-to-reach takes time due to poor or nonexistent roads, difficult terrain, and long distances to travel. Given the need to reach these communities with the polio vaccine, and the time and resources required and the additional health needs in these areas of Nigeria, the mobile outreach of the reaching every ward/district (REW/RED) was adopted. The REW strategy provides evidence of an improvement in the delivery of routine immunization services as well as strengthening the immunization delivery system to meet the need for integrated delivery of other child and maternal survival interventions [7]. Furthermore, the traditional immunization service delivery system is not sufficient for rural, hard-to-reach areas [8]. Vaccination in combination with other interventions has been shown to improve child survival outcomes [9, 10]. The Government of Nigeria implemented vaccination in hard-to-reach communities with support from the World Health Organization (WHO) to address the issues of health inequities in the underserved communities where, often, the population immunity for polio is inadequate. This paper documents the process of conducting integrated mobile vaccination in hard-to-reach areas and its impact on immunization outcomes.

We conducted vaccination in hard-to-reach populations in 2014–2015. Using epidemiologic and program criteria (i.e., analysis of the supplemental immunization activities (SIAs) micro-plan settlement profile data), the polio program selected 2311 hard-to-reach settlements in the four states which were at risk of sustaining wild poliovirus (WPV) transmission in 2014. Of these, 763 were in Bauchi, 620 in Borno, 406 in Kano, and 522 in Yobe states (Fig. 1).

The hard-to-reach intervention was implemented in 2311 preselected, nonurban, hard-to-reach and underserved communities in 316 wards in 67 very high-risk LGAs in Bauchi, Borno, Kano and Yobe states (Table 1). The mobile teams submitted reports of the sessions conducted on a weekly basis and also transmitted real-time information capturing the time that sessions were started and completed, and the geographic location of the settlement where sessions were conducted.

The OPV3 coverage among children under 1 year old showed an upward trend within one quarter in all the states, with Borno having the highest coverage of 80% in the first quarter (Table 2). The overall cumulative coverage for all the states was 38% for the first quarter of implementation, July to September 2014. By the second quarter of implementation (October to December 2014), all the states showed improvement in OPV3 coverage to 48, 44, and 47% for Bauchi, Borno, and Yobe states, respectively, except for Kano which reported only 18%. The OPV3 coverage by the July to September 2015 quarter was 65% for Bauchi, 61% for Borno, 73% for Kano, and 44% for Yobe (Table 2).

Targeting children aged 1–5 years with OPV showed an increasing trend (Fig. 2); it had consistently gone beyond 90% for the period of implementation, with coverage above 100% in April to June and July to September 2015, due to influx of more clients from outside the planned catchment areas to access treatment, which was provided free of charge.

The coverage of the third dose of the pentavalent vaccine (penta3) was very low in all the states during the first quarter of implementation (6% in Yobe and 9% in Kano states; Table 2), but increased to 41 and 73%, respectively, by September 2015. Overall, the penta3 coverage increased from 20% at baseline to 54% by September 2015 across all the implementing states.

Vitamin A, albendazole (an antihelminthic agent), and malaria treatment were administered to children under 5 years old (Fig. 3). Of the targeted children, 78% were provided with vitamin A in July to September 2015, an increase compared with the earlier quarters. The proportion of children dewormed, however, fluctuated between the different quarters of implementation with the highest recorded in October to December 2014. There was a decreasing trend of children provided with treatment for malaria in the period under review. This ranged from 14 to 9% from October–December 2014 to July–September 2015. A rapid diagnostic test (RDT) for malaria was introduced as part of the roll-back-malaria treatment policy of prescription of antimalarials to only those who tested positive for the malaria parasite.

A total of 24 cases of acute flaccid paralysis (AFP) were reported from the hard-to-reach settlements over the period of implementation (Table 3). Investigations were conducted, and stool specimens were collected and sent to the national polio laboratory, but all the result were confirmed to be nonpolio AFP.

We found a steady increase in OPV3 and penta3 vaccine coverage in the hard-to-reach areas during the period of implementation of mobile health sessions. The coverage of supplemental doses of OPV to children up to 5 years of age also improved. This finding agrees with those from Bangladesh and India where combined interventions improved the child immunization coverage in rural hard-to-reach areas [5, 14]. The package of intervention provided included services and commodities that addressed the unmet health needs of the communities, which created demand and led to overwhelming acceptance and support for the mobile health teams during the session, despite being previously noncompliant to polio vaccination teams [15].

An increasing number of children received vitamin A and antihelminths, while pregnant women were provided with intermittent preventive therapy (IPT) with an antimalarial. Similarly, the finding of the strategies to reproductive, maternal and child health in difficult to access mountainous locations show that there is benefit for comprehensive, regular outreach teams for service delivery and coverage. Integrated care, community health workers and regular supply of commodities immensely reduce morbidity and mortality of children and women.

We also found that the mobile teams conducted active searches and reported AFP cases from the hard-to-reach settlements. All the cases revealed nonpolio AFPs, in contrast to the NPEEP report where over a third of the polio cases in 2013 were from hard-to-reach settlements [6].

Although the interruption or absence of WPV in the hard-to-reach might not be attributed to the hard-to-reach interventions alone, it is worthy of note that these interventions have also contributed towards improved maternal and child health indices. As in other studies documenting an improvement in routine immunization programs, this study was not conducted using standard research protocols since research was not the primary purpose of the work. The reaching the hard-to-reach project was an intervention to improve population immunity that integrated immunization and other maternal and child health services [16].

Real-time reports from the teams improved accountability and ensured that they conducted the sessions according to plan. Although it may not translate to improved coverage and population immunity, this served as a monitoring and accountability tool which ensured that the sessions were held as planned [17, 18].

Although we did not determine the cost per session for the hard-to-reach in this study, the intervention had the benefit of delivering vaccines and other interventions to areas that would have continued to be missed, with a possible consequence of polio outbreaks. The outreach also provided an opportunity for clients from neighboring settlements not included in the initial plan to benefit from these services.

Although the hard-to-reach activities improved OPV and other child survival intervention coverage, a cost-benefit analysis of the intervention should be conducted. The outcome, regarding the benefit and lessons learnt, could be used as an advocacy tool to encourage the government to buy-in to integrated mobile outreach and strengthen primary health care in the states.

Hard-to-reach areas will continue to exist, and their underserved populations are vulnerable to diseases. Mobile outreach to these communities should be established and integrated into the routine immunization outreach service delivery plans, or it could be expanded into a more integrated and well-financed mobile (motorized) outreach program, where the minimum health package could be provided. The hard-to-reach strategy should also be aligned with the one primary healthcare center (PHC) per ward approach in the medium- to long-term planning. Furthermore, government at respective levels should be involved in the planning phase to ensure buy-in and sustainability of the outreaches to the hard-to-reach areas.

The hard-to-reach project has improved population immunity against polio in the hard-to-reach and underserved communities and also improved the delivery of other child and maternal health survival interventions. Ultimately, there should be improved and sustained coverage of the target population with the specified interventions. Furthermore, it has improved reach, addressed inequity to healthcare access to underserved communities, and contributed in interrupting transmission in the states at high risk for polio in Nigeria.

The hard-to-reach project was implemented to address gaps in population immunity among the inaccessible communities in communities at high risk for polio. Using this integrated approach, routine vaccines and other child health survival interventions were provided to the hard-to-reach and underserved communities. This contributes to polio eradication, health indices, and universal health coverage.