Weaknesses in design
Gaps in reach. Excluding secondary school students from the targeted population after SNP2 meant that households with only older children (in addition to those with none) were no longer reached by either SNP or ANC/EPI distribution—except through the relatively uncommon event of inter-household redistribution of nets. These included households with older adults whose children had grown past school age, households made up of young families who did not yet had children, and single or transitory workers living in shared housing. While such households were likely to benefit from the community effects of nets given the high levels of usage and ownership in SNP areas, questions of equity and reach need to be considered. Tanzania’s current National Strategic Plan has a commercial sector component intended to boost ITN sales so that all households would be able to purchase an ITN when they need a new one, but unfortunately, most purchased nets are untreated [
20]. As the programme expands, it will be critical to determine if local variation in school enrollment will result in compromised coverage effects in some parts of the country, and whether varying the number of targeted classes will be able to mitigate this.
Overestimate of net lifetime. While predictions of cost per person-year of protection and per net distributed from before the initiation of the SNP were relatively accurate, predictions of use and ownership were somewhat optimistic. One important reason for overestimation was a reliance on an overly optimistic estimate of net lifetime. The lower observed coverage highlights the importance of, at a minimum, gaining a better understanding of LLIN lifetimes to drive procurement quantifications and plan for future distribution to reach pre-determined coverage targets. Overly pessimistic estimates of net lifetime will lead to oversupply of nets while overly optimistic assumptions will result in insufficient coverage and potentially insufficient protection.
Challenges in implementation
Timing of first SNP and interruption in routine delivery. The TNVS ended in July 2014 after an audit uncovered fraudulent activities by health facility staff, retail outlets, and sales representatives [
11]. After a two-year gap in distribution targeted at pregnant women and infants, distribution to these populations was slowly reinstated via free LLIN distribution through ANC and EPI. This gap in routine delivery led to significant undersupply of nets when compared to original planning for the SNP in 2011. Likewise, the 2011 Keep Up Strategy projected SNP to begin in 2012, while it did not start until mid-2013, nearly 3 years after the last mass campaign in the three targeted southern regions.
Large number of distribution points. The large number of schools and hence distribution points for the SNP posed a major operational challenge. The project began with 2337 primary and secondary school distribution points and expanded to 9535 primary school distribution points across the 14 targeted regions by the fifth round of SNP. The operational scope is similar to mass campaigns, which had 2668 distribution points in the 2010-2011 UCC in the three originally targeted southern regions, and 11,717 issuing points for the UCC in the 14 regions currently targeted for SNP. SNP shared some operational challenges with other large-scale net distributions, such as identifying the optimal cascade training design, having consistent cellular network service to facilitate mobile-money payments for trainees and supervisors, and data entry errors and delay as reports were aggregated. Sensitization meetings with local officials and trainings for various actors were relatively intense in the first rounds; these were reduced or eliminated entirely in subsequent rounds as the programme became institutionalized.
During SNP1, LLINs were stored for several days so that all schools could distribute nets on the same day, region-wide; this was eliminated in later rounds to avoid storage and security costs. LLINs were given to teachers in targeted classes in SNP1. This practice, along with paying allowances for issuing and reporting, was eliminated in later rounds as the time involved was minimal and recognized as part of teachers’ job duties. Ward Education Coordinators (WECs) initially visited schools to collect enrollment data, which was cumbersome to manage. School data validation visits were employed in SNP2 and SNP3, but eliminated, along with the WEC role, for SNP4 when the President’s Office Regional Administration and Local Government offices (PO-RALG) established the Basic Education Management Information System (BEMIS) to track enrollment data. Data from the BEMIS were used to establish LLIN quantifications and LLIN transport plans. Logistics were also streamlined over time-in the first rounds, LLINs were delivered to the district councils and re-bundled for separate onward transport to various schools. Switching to a ‘mobile warehouse’ strategy where larger trucks dropped off nets at schools along pre-identified routes reduced costs, as did switching in SNP4 from offloading, storing, and reloading at regional warehouses to a ‘cross-docking’ system whereby LLINs were received virtually by regional authorities, but offloaded directly to the smaller ‘mobile warehouse’ trucks. Starting in SNP5, transport was done by a third-party private logistics firm, with delivery timeframes and confirmations sent by SMS to district council officials and implementing partners. The ministry of local governments (PO-RALG) increased their involvement in the activity over time, given their oversight of local-level health and education activities. As SNP expanded to additional regions, the timeframe of the annual activity lengthened. LLIN shipments were planned to arrive in two to three phases, scheduled around examination periods and vacations. In limited cases, deliveries occurred after exams when Standard 7 students had already left school. Timing distribution around holidays, national exam schedules and local events also poses a planning challenges, as school distributions must align well with school calendars which can vary significantly even within small areas.
Acceptability to stakeholders and beneficiaries. The reactions of stakeholders and beneficiaries has been largely positive, with students and teachers generally looking forward to the SNP. In parallel, local government involvement and leadership has grown over time [
21]. Through the planning discussions for SNP1-3, NCMP and PO-RALG centralized data and improved the systems, allowing both government and implementing partners to access the data at a central level. As a result of this collaboration, the SNP helped PO-RALG formalize data management related to enrolment, hence offering an appreciated service. Since SNP4, the consensus was that work was easier—classes were preidentified without costly and time-consuming visits to collect or verify data, and distribution occurred the same day nets were delivered. Others also felt that the programme reduced malaria cases in student populations. SNP has also led PO-RALG, the MoEVT and the MoH-CDGEC to coordinate more closely, an important development towards multi-sectorial malaria control activities.
There are also ongoing concerns with some elements of the programme, especially with regards to groups that are missed by the SNP. This includes dissatisfaction among students enrolled in schools but not in eligible classes in a given year, especially those in the youngest classes and the pre-school classes (kindergarten classes). It also includes students enrolled in schools that may be missed because they are not part of the regular Ministry of Education System, such as schools for students with special needs, which may not be identified through the regular school quantification system. Extra care must be taken in future SNP-like programmes to ensure that such schools are enumerated and included. In addition, in some early years, teachers were included as beneficiaries (hence they received a net), but in more recent years they have only been programme participants. The teachers repeatedly reported the desire to be included in the programme as beneficiaries [
21].
Quantification of net needs. In addition to the original modelling that explored the theoretical framework for the SNP, for each SNP round, NetCALC was used to conduct quantification before net procurement and deployment. Several challenges and some lessons learned through this process have led to improvements in the overall quantification modelling process. The original NetCALC software could only predict ownership of at least one net at the household level (though this was modified to also predict use for the initial SNP planning) [
12]. Subsequent versions of the modelling software were updated to formally predict ITN population access. During SNP1-3, ownership of any ITN was the target used during quantification, while population ITN access was used to quantify net needs after SNP4, resulting in better planning alignment with national strategic goals. Regardless of the target indicator used for quantification, net lifetime was an important parameter which needed considerable revising over time and still require local monitoring [
16,
17]. The use of an Excel-based tool limited options for an effective, error-free workflow and created opportunities for data entry error as the programme expanded in scope and became more complex. A NetCALC algorithm in software that is more reproducible has become available and may be useful moving forward [
22]. Higher resolution data in time and space, such as was available due to routine evaluation was helpful for quantification, as LLIN needs could be locally recalibrated each year and the strategy adjusted based on these data [
15]. This was especially true in the early rounds of SNP, when assumptions about the reach of the strategy were confronted with the realities of the three-year gap since the previous mass campaign and the discontinuation of the TNVS. Given the variations in enrolment by region, as well as different starting years and starting levels of ITN access, good monitoring will continue to be important to track ITN access on a regional basis, gathering data, and adjusting net quantities to maintain high rates of ITN access.