Fear.

Fear was a prominent theme in the implementation of polio programs. Fear was associated with rumors, suspicions, and past experiences with other diseases, rendering parents reluctant to take up polio programs. Coincidentally, fear also facilitated program implementation as fear of illness due to polio increased vaccination uptake. Under this theme, nine studies mentioned a total of five barriers, and one study highlighted fear as a facilitator.

One study stated that the presence of rumors discouraged families in Ethiopia from having their children vaccinated due to fears of inducing sterility and/or disability [14]. This same study, along with six others, highlighted suspicions of immunization side effects as a barrier to implementation [14–20]. Suspicions included actual and perceived side effects, ulterior motives of the government, and infertility. For instance, one study described that in India, “most [participants] said that there was resistance among the population in some areas due to the fear that OPV [oral polio vaccine] causes infertility” (p. 5) [17]. Moreover, one study highlighted the fear that families had regarding the vaccination being experimental [21]. Lastly, one study identified fear of vaccines due to past Ebola experiences as a deterrent to polio vaccine uptake [22]. Attributing fears related to past Ebola experiences in the region, participants in Liberia “recounted how immunization teams had worn personal protective equipment and that this caused communities to be afraid” (p. 86) [22] of polio immunization.

Related to the beliefs of individuals, one study highlighted fear of contracting the disease as a facilitator to polio immunization uptake. The authors of one study in Nigeria stated that participants felt that “their fear of disease overshadowed the perceived risks of vaccination” (p. 3324) [15].

Community trust.

Community trust in organizations and governments was also a key theme in the implementation of polio programs. Distrust stemming from political and social exclusion hindered programs’ credibility in certain communities. On the other hand, trust served as a facilitator in program uptake in certain settings where trust in government services was high. Under this theme, two studies identified three barriers. One study stated this theme as a facilitator to polio immunization acceptance.

One study explicitly identified government distrust as a barrier to intervention acceptance in India [18]. The respondents of this study “were more likely to blame the government and polio workers” when discussing reasons for avoiding vaccination (p. 14) [18]. In addition, one study mentioned the resistance of participants living in Pakistan due to the lack of basic health facilities in their communities [20]. This lack of infrastructure was a primary cause of mistrust, and, consequently, resistance to OPV. Moreover, this study also discussed refusal of intervention uptake as a means of protest against the government in order to address their political and economic problems.

One study described increased trust in government health services and thus acceptance of vaccination when improvements were made to these services across seven countries (Nepal, India, Pakistan, Ethiopia, Nigeria, Rwanda, and Angola) [23]. A frontline worker from this study stated that “one manifestation of this trust [in government health services] was acceptance of vaccination” (p. 15) [23].

Infrastructure.

Infrastructure was another theme identified in the implementation of polio programs. General infrastructural issues impeded effective implementation and limited efforts to reach vulnerable populations. Conversely, in the presence of good infrastructure and resource mobilization, the implementation of polio programs was deemed successful. Under this theme, nine studies mentioned a total of five barriers, and three studies mentioned a total of three facilitators.

One study highlighted that in Nigeria, the general lack of basic necessities, including drug availability in hospitals and water service, is a barrier to future immunization uptake [15].

Eight studies highlighted available resources as a challenge to the effective implementation of polio programs [14, 17, 18, 21, 23–26]. The lack of access to healthcare was mentioned by one study in Niger, where the majority of respondents noted inaccessibility as impeding routine immunizations and acute flaccid paralysis surveillance [24]. Two additional studies highlighted financial, organizational, operational, logistical, and quality barriers to the delivery of immunization services across several countries, including Nepal, India, Pakistan, Ethiopia, Nigeria, Rwanda, and Angola [14, 23]. The study conducted in Ethiopia listed “shortage of vaccine and supplies, non-functionality of refrigerators, lack of training, cancellation of immunization sessions, and unavailability of health posts to deliver the services” (p. 33) as possible reasons for low immunization [14]. Moreover, the unavailability of eligible children was considered a barrier by four studies across Pakistan, Afghanistan, and India [17, 19, 25, 27]. Children were frequently missed during polio vaccination visits and were not followed up with at a later time. In a 2017 study in Pakistan, “38 percent of children were not vaccinated with OPV,” and the most frequent reason given was “the unavailability of children at home during polio vaccinator visits” (p. 29) [19]. Lack of general infrastructure, including access to hard-to-reach flood plains, weak health infrastructures, and insufficient financing for strategy implementation, impeded effective polio implementation in one study [26].

Furthermore, three studies listed the availability of resources as a facilitator in some settings [25, 28, 29]. First, one study highlighted a good social mobilization system in Afghanistan, where mobilizers visited over “90 percent of targeted, low-performing communities in the South” (p. 170) prior to the program’s implementation [25]. In addition, the finding and mapping of marginalized populations across seven countries in South Asia and sub-Saharan Africa facilitated the targeting of children who may have been missed during polio visits in one study [28]. Lastly, one study in Uganda highlighted increased accessibility to immunization due to close National Immunization Days (NID) posts as facilitating individuals’ participation in routine immunization campaigns, citing “NID posts very near and within a short walking distance” from their homes (p. 367) [29].

Beliefs about the intervention.

The most prominent theme discovered in the implementation of polio programs surrounded beliefs related to the intervention. Negative beliefs about the polio vaccine emerged from cultural beliefs, religious conceptions, and inadequate awareness of the vaccine’s purpose and effectiveness. However, increased knowledge and positive beliefs about the vaccine’s efficacy against disease facilitated program implementation in other settings. Under this theme, 11 barriers from 15 studies, and four facilitators from seven studies were identified.

Anti-immunization debates were thought to negatively contribute to the community’s trust in the vaccine. For instance, anti-immunization debates challenged the immunization program in India [30]. The authors of this study highlight that frequent debates challenging immunization programs “began to influence the community’s trust in the vaccines” (p. 7).

When considering the presence of particular beliefs about the intervention, 14 studies mentioned a total of nine barriers. An additional seven studies listed a total of four facilitators.

Propaganda and mistrust against vaccines and their efficacy were mentioned by two studies as the reasons for parental vaccine refusal in India [17, 31]. An additional study identified the importance of cultural beliefs in the decision to reject the vaccine in Niger [24]. Categorized under knowledge and beliefs about the intervention, seven studies mentioned refusal of polio program uptake due to a lack of information, ignorance, and illiteracy across Pakistan, Nigeria, India, and the United States of America [15–17, 19, 21, 27, 32]. For instance, in Nigeria, the majority of refusal respondents mentioned “drinking of clean water as a way to avoid polio virus, [while] others identified [that] ways to protect against polio included proper care and belief in God” (p. 3326) [15]. The belief that vaccination was unnecessary was cited as an indicator of refusal and thus a barrier to intervention uptake across four studies [15, 21, 23, 25]. Moreover, a study in India identified vaccine-resistant areas in a particular district as a barrier [30]. Safety and religious misconceptions regarding the vaccine were mentioned by two studies, which included witchcraft accusations and Westernized medicines that threaten religious credentials [19, 23]. In Pakistan, the misconception that “the vaccine is not ‘halal’ or [that it is] impermissible in the Islamic Law” (p. 27) [19] was a major reason for vaccine refusal. The perception of age, particularly being “too old,” and lax or disinterested parents were deemed as reasons by participants in one study to avoid polio vaccination in the United States of America [33]. Additionally, the reliance on religious leaders that oppose OPV uptake fueled skepticism and resistance in one study in Pakistan [20]. Lastly, one study mentioned mothers avoiding OPV by running away with their children as a barrier to polio campaigns in India [17].

Parents’ moral obligation to vaccinate their children and their belief that they cannot be deviant was mentioned by one study as a facilitator to polio intervention use in India [31]. Additionally, four studies across the United States of America, Uganda, India, and Pakistan highlighted the belief in the vaccine’s ability to protect against polio as a facilitator [20, 21, 29, 30]. Participants of one study in Uganda said that “the major aim [of the vaccine] was to ‘weaken’ the disease and/or ‘strengthen’ the children’s capability in fighting diseases” (p. 367) [29]. The public’s awareness of polio vaccines and the intervention in general were mentioned by three studies as a positive influence on uptake [19, 22, 23]. Lastly, one study described the decrease in religious resistance to OPV as associated with the defeat of militants and increased involvement of religious scholars in the polio vaccination campaigns in Pakistan [20].

Influential opinions.

Influential opinions was a theme that emerged that was closely tied with acceptance of the polio program. Some religious leaders and health professionals were not in support of the polio programs. Because the opinions of these groups were heavily influential in parents’ decision-making, they served as a hindrance to program implementation. On the other hand, religious leaders and health professionals who served as champions of the vaccine were helpful in facilitating program implementation. Under this theme, five barriers were identified by six studies, and three facilitators were identified by four studies.

The meaning and values attached to the intervention by health workers and opinion leaders was cited by two studies as a challenge in the implementation of polio interventions [29, 31]. First, one study in India stated medical practitioners’ opposition against repeated rounds of polio vaccination as a barrier to implementation [31]. These private medical practitioners “advised their clients against vaccination as they thought it was unnecessary for children in Kerala” (p. 6) [31]. Moreover, another study conducted in Uganda highlighted the influence of health workers and opinion leaders, as laypeople emulated their refusal to vaccinate their own children [29]. In both cases, reservations about the intervention were influenced by individuals who may be involved at some capacity in the intervention or whose opinions concerning the intervention may be perceived as credible.

One study identified health workers and opinion leaders’ refusal to vaccinate their children as a negative influence on participants in Uganda [29].

Protests by alternative medicine providers, including active discouragement by homeopathic practitioners, was a barrier mentioned by one study in India [30]. For instance, “many homeopathic practitioners have actively discouraged their clients from immunizing their children,” exerting strong influence on households in northern Kerala and “convincing them against immunization” (p. 7). Another study highlighted the reliance on religious leaders that oppose OPV as a barrier to polio immunization interventions in Pakistan [20].

Four studies described champions as facilitators to intervention implementation. First, three studies highlighted the influence from health-focused champions in endorsing the uptake of polio vaccination, thus positively influencing the decision-making process of participants across the United States of America, India, Nepal, Pakistan, Ethiopia, Nigeria, Rwanda, and Angola [21, 23, 30]. Moreover, one study described the involvement of religious scholars as decreasing religious resistance to OPV and increasing the acceptance of the vaccine [20]. Participants of this study noted that “the involvement of religious scholars in the OPV campaigns also helped the cause of polio eradication,” decreasing the number of non-compliant parents (p. 3701). Lastly, the decrease in religious resistance to OPV through the defeat of militants and the increased involvement of religious scholars positively influenced polio vaccination uptake in one study [20].

Intervention design.

Intervention design was another theme that emerged from the implementation of polio programs. Strategies to reach target populations were a challenge as the resources needed for such mobilization were not available or convenient in some settings. However, in other settings, strategies including policies that enforce polio vaccination served as facilitators to program implementation. Under this theme, two barriers and four facilitators were mentioned across three and four studies, respectively.

Four articles listed aspects of design quality and packaging as either a barrier or facilitator to polio immunization programs. First, the absence or failure of vaccination teams to visit homes to administer vaccines to children in Afghanistan and Pakistan were listed as barriers by two studies [19, 25]. The study in Pakistan revealed that “29 percent of children did not receive OPV due to absence of polio vaccination teams from their duty” [19] (p. 29), underscoring the gap in implementation programs to reach vulnerable children. Moreover, the frequency of visits needed for booster shots of the polio vaccine in Pakistan was mentioned by one study as a deterrent to vaccination uptake [16].

On the other hand, the multiple polio campaigns in numerous countries, including Nepal, India, Pakistan, Ethiopia, Nigeria, Rwanda, and Angola, were deemed a facilitator to implementation; one study revealed that many respondents asserted the effectiveness of several campaigns [23]. In a 2016 study, respondents stated that “people were happy with polio campaigns, largely because they no longer had to fear polio” (p. 9) [23].

The Pakistani government mandating polio vaccination in order to fly abroad was underscored as a facilitator to intervention uptake by one study [20]. By mandating “presenting polio vaccination certificates to immigration officers at airports before flying abroad” (p. 3697), the government was able to enforce legal measures to encourage the uptake of vaccines.

Moreover, two studies mentioned coercive means as a facilitator to intervention uptake [15, 31]. In one study, emphasis on coverage results and the use of coercive means restricted options for refusal in India [31]. Moreover, another study in Nigeria noted that “a majority of the acceptors presented their children for vaccination because they had been told to do so” (p. 3325) by health workers [15]. The way in which the intervention was presented in these two sites (deeming it to be mandatory) facilitated uptake.

Geo-politics.

Geo-politics was also a theme that emerged from the implementation of polio programs. This theme emerged from several barriers that could not be coded using the CFIR. These barriers were external to the intervention itself but negatively influenced the implementation of programs across several settings as many children who were eligible for vaccinations were inaccessible. These barriers included the relocation of mothers mentioned by two authors [14, 17], the inaccessibility to reach children highlighted by one author [25], and conflict and security issues described by two studies conducted in Pakistan [16, 34]. For example, one author noted that “the global war on terror and the geopolitical situation in Afghanistan impacted polio eradication and other immunization efforts in the country” (p. 7) [34].