The history of mass polio campaigns (Immunization Plus’ Days or IPDs for short) dates as far back as 1988 when the world health assembly declared a plan for polio eradication (https://www.who.int/news-room/detail/25-05-2017). Before then, the disease had ravaged the globe with a burden of over 350,000 paralyzed polio victims every year (https://www.who.int/news-room/fact-sheets/detail/poliomyelitis). The World Health Organization (WHO) provided 2 main strategies as a method of freeing the world completely of polio: namely immunization (of which there are several types) and acute flaccid paralysis AFP surveillance (http://www.emro.who.int/polio/strategy/). Using these strategies, there has been remarkable reduction in the number of polio cases worldwide with the disease virtually nonexistence in most countries. Indeed, the only remaining polio endemic countries on the globe as of today (year 2019) according to the WHO are Pakistan, Afghanistan and Nigeria (polioeradication.org/polio-today/polio-now/this-week/).
The Nigeria polio problem is a composite of several interwoven factors. These include: noncompliance to immunization, insecurity and vaccination team attitude. Noncompliance to immunization refers to households that are averse to immunization and these abound in the country, particularly in the northern region (Abdulaziz Mohammed et al., 2014). In this part of the country, there still exists many who do not believe in immunization. Consequently, even when presented with vaccines by health workers going house to house during mass polio campaigns, they do not allow their children to be vaccinated. Hence their young children are at a very high risk of polio infection, and as a result the region has found it difficult to interrupt transmission of polio.
Also, in large swaths of the northern region, communal clashes (either herdsmen versus farmers or clashes of ethnic origin) together with armed banditry and terrorism have rendered many communities inaccessible to vaccination teams (WHO, Adamawa state January 2019 IPDs). Pundits argue that until all children trapped in inaccessible communities (settlements) are served polio vaccination, transmission of polio will continue to thrive in Nigeria.
Vaccination team attitude is the (negative) behavior and performance of health workers who work to support polio vaccination. Many public health experts believe that this may be the greatest problem bedeviling the nation’s polio program as it cuts across all regions of the country. Vaccination team attitude can have negative impacts on the program in several ways, including: vaccinators deliberately refusing to visit settlements of assignment during campaigns; vaccinators simply dumping polio vaccine while falsely adding the number of names to the tally sheet corresponding to the number of doses poured away; vaccinators colluding with heads of noncompliant households to mark children as vaccinated (a finger mark with indelible marker) when they do not, in fact, receive the vaccine, and so on and so forth.
Despite these problems, the country has nonetheless recorded and continues to record great success in stopping polio (polioeradication.org/where-we-work/nigeria/). Much of the success achieved in polio eradication initiative (PEI) in the country today is attributable to the intervention of government at all levels and many NGOs directly tackling these problems of noncompliance, insecurity and team attitude. One particularly impactful innovation that perhaps can be called the game changer in the history of polio eradication in Nigeria (https://www.slideshare.net/.../how-the-polio-eradication-effort-in-nigeria-led-to-a-quest-for-global-geospatial-reference-data), was conceived and implemented by the GPEI partners (mainly WHO, NPHCDA, and the Bill & Melinda Gates foundation) in 2011. This innovation, called the Vaccination Tracking System (VTS), employs GIS technology to track vaccinators and hence ensures that all settlements are, in fact visited, as well as giving immunization coverage at the end of every mass campaign on a monitoring screen (called the GIS dashboard - vts.eocng.org/Home/About). This technology simply involves giving well charged android phones (that collect GPS tracks every 2 minutes) to vaccinators during working hours of any mass polio campaign. At the end of each day’s activity, the phone data are uploaded to a central server, and GIS software (ArcMap, ESRI, USA) is used to reveal the GPS locations of where the vaccinators spent the day. The data is also shown on the VTS website (http://vts.eocng.org/) and is then exported to the GIS Dashboard, and contains accurately drawn GIS maps of the entire country, with all human habitations - namely towns, villages and hamlets -painstakingly named and identified with geocoordinates (Inuwa Barau, Mahmud Zubairu, et al., 2014). Any human habitations without GPS tracks are classified as “missed” as there is no evidence they were visited/reached by vaccinators. And those with only very few tracks are “poorly reached/covered.” Built-up areas (urban) are divided in to a 50 meter grid, and coverage is based on the number of grid squares intersected by a track. Overall coverage is then calculated and displayed on the GIS dashboard during and after polio campaigns (www.vts.eocng.org). Since the introduction of VTS, the progress of the Nigeria polio program has improved significantly and many public health experts believe that eradication is imminent.
Prior to every house to house mass polio immunization campaign in Nigeria a micro plan containing details of all settlements (whether towns, villages or hamlets) within a given region of assignment is prepared by the Ward microplan revision team - a gathering of the traditional leaders, vaccinators and health workers resident in the ward. With a comprehensive line list of settlements within a ward (like Horserizum of Hong LGA of Adamawa, Nigeria), it should not be difficult for vaccinators to cover all areas during immunization campaigns, except for two reasons: namely poor team attitude and/or a faulty micro plan. With intensive supervision coupled with vaccination tracking of health workers, team attitude is surmountable. But what about faulty micro plan? A faulty micro plan implies not all settlements in the ward were actually line-listed in the first place by the ward micro planning revision team. In order to tackle the issue of the faulty micro plan the GPEI partners began the collection of georeferenced settlement data for all wards in Nigeria. (Vince Seaman 2014). The maps were constructed by obtaining all X and Y coordinates of line listed settlements on the existing ward micro plan and viewing them on satellite imagery. Each map is thoroughly scrutinized and any settlements seen on the imagery which were not identified by the initial data collection were flagged and assigned machine or computer generated names - SSA (if they appear like a village) or HA if they look like a hamlet area.
The GIS maps revealed faulty micro plans in nearly every Ward across the country. The maps in most cases contain about 5% machine-named SSAa and HAs that are totally unknown to ward micro plan revision teams. It therefore comes as no surprise that despite many rounds of mass polio campaigns in Nigeria, many SSAs and HAs are not reached by vaccinators not because they deliberately refuse to do so (team attitude) but due to a faulty micro plan! Experts agree that once vaccinators are tracked (given phone trackers during mass polio H2H campaigns) and micro plans thoroughly revised such that each and every human habitation in a ward – including machine named SSAs and HAs are assigned locally recognizable names, then, the issue of low immunization coverage due to missed areas (settlements not reached by vaccinators after campaigns) would be over. Such a revision of ward micro plans for mass polio campaigns using GIS drawn maps is what is called GIS micro planning and is the bedrock of this study.