Outcomes of a Social Media Campaign to Promote COVID-19 Vaccination in Nigeria

"...there is evidence that the campaign produced measurable and practically meaningful positive effects on social norms and vaccination status."



Both supply and demand for COVID-19 vaccination in low- and middle-income countries (LMICs) are major issues in controlling the pandemic worldwide. Specific issues in LMICs include the 5 Cs of vaccine hesitancy (confidence, complacency, convenience, communications, and context), social norms around vaccination, and mis- and disinformation, among other challenges. This paper describes a national-level quasi-experimental evaluation of a social-media-based COVID-19 vaccination promotion campaign in Nigeria. Run in 2022, the campaign was based on a theory of change (ToC) that posited that promoting positive social norms in favour of vaccination, reducing vaccine hesitancy, and promoting pro-vaccination motivation, opportunity, and ability (MOA) to be vaccinated would collectively lead to higher vaccination rates.



The campaign was designed and delivered by a separate team of designers and local organisations in Nigeria who created social media content and delivered it on Facebook and Instagram. Local organisations included healthcare organisations, businesses, religious groups, and similar prominent leaders with a substantial, existing social media presence and network. Content consisted of graphics, videos, and other social media materials such as GIF (graphic interface format) images. The campaign was run in 2 phases, from January to February 2022, and from May to September 2022, corresponding to the time periods just after baseline, before the first follow-up, the period after the first follow-up, and just before the second (endline) follow-up.



The researchers followed a longitudinal cohort of Nigerians (at baseline) drawn from all 37 states in Nigeria over a 10-month period. In a quasi-experimental design, participants in 6 Nigerian states where the social media campaign was run (treatment) were compared to participants from non-treatment states. There were 1,100 participants from the 6 campaign (treatment) states and 833 from the 31 comparison states. Of these, 1,155 (59.8%) completed the first follow-up questionnaire, and 462 (23.9%) completed the second follow-up questionnaire.



The primary endpoint in this study is COVID-19 vaccination uptake. This was assessed using a single questionnaire item that read, "Have you received a COVID-19 vaccine?" The study also had two secondary endpoints. The first was vaccine hesitancy, an index defined as the mean of coded responses to 5 questionnaire items reflecting the 5 Cs framework. The study's other secondary endpoint was pro-vaccination social norms, a scale score defined as the mean of coded responses to 5 questionnaire items - e.g., "Your friends think it is important for everyone to get a COVID-19 vaccine" and "Your family members think it is important for everyone to get a COVID-19 vaccine". The response options for each were "Strongly disagree", "Disagree", "Neither agree nor disagree", "Agree", and "Strongly agree".



The study found that vaccination rates increased in treatment states compared to non-treatment states and that these effects were strongest between baseline and first follow-up (December 2021 to March 2022). At the first follow-up, 31.7% of retained participants from treatment states had been vaccinated, compared to 25.3% of retained participants from comparison states who had been vaccinated, for a crude difference of 6.4 percentage points (p = 0.045) and an adjusted difference of 7.8 percentage points (p = 0.020). While the magnitude of these differences were even greater at the second follow-up, there were 9.1 and 11.0 percentage points of higher vaccination among retained treatment state participants compared to comparison state participants; the results approached but did not reach the level of statistical significance, defined as P < .05.



In addition, more pro-vaccination social norms at one time point were associated with higher vaccination rates at a later time point. All the crude and adjusted odds ratios for pro-vaccination social norms are statistically significant, and the models suggest that a unit increase in pro-vaccination social norms increases the odds of being vaccinated between waves by 50 to 60 percent. This finding suggests that pro-vaccination normative beliefs may be an important driver of COVID-19 vaccination.



Reflecting on the findings, the researchers indicate that the fact that social norms were hypothesised as one mediator of the effects on vaccination provides support for the campaign's ToC. Further analysis of the potential mediating effects of social norms on vaccination should be conducted, they argue, and future research should examine the potential for social norms to be a mediator of COVID-19 and other vaccine uptake. One future avenue for new interventions is to identify normative beliefs that increase vaccine hesitancy or otherwise serve as barriers to getting vaccinated, such as motivations and beliefs about opportunities and ability to get vaccinated (per the MOA framework). Myths and misinformation about the effects of COVID-19 and other vaccines (e.g., that they cause infertility) are likely part of the mosaic of normative beliefs that increase vaccine hesitancy, and they should be addressed through messaging and other intervention strategies.



The researchers identify future research priorities in this area, such as employing stronger quasi-experimental designs (e.g., cluster randomisation) in future studies on social media programmes to promote vaccination. Also, one area to explore further in future research on such campaigns is the mechanisms by which social norms are changed and influence vaccination outcomes via social media. It is possible that social media may create a widespread sense of engagement in preventative behaviours and social acceptance of behaviours such as vaccination against COVID-19 and other diseases.



In conclusion: "Social media has the potential to influence vaccination rates in LMIC settings, and there is evidence to suggest that social norms are a promising mechanism to communicate pro-vaccination messages."