Pharmacists and COVID-19 Vaccination - Considering Mobile Phone Caller Tunes as a Novel Approach to Promote Vaccine Uptake in Low- and Middle-Income Countries

"The use of mobile phone caller tunes could be a welcome addition for use by pharmacists to help combat disinformation and hesitancy, and promote widespread vaccination as availability increases."

COVID-19 vaccine hesitancy could threaten the success of vaccination programmes as they are being rolled out in several low- and middle-income countries (LMICs). This article proposes that pharmacists could play a role in addressing COVID-19 vaccine hesitancy by leveraging mobile phone caller tunes. With this technology, which is used in LMICs to promote popular songs and religious messages, callers to mobile phones hear a message or a song instead of the typical ringing sound. As is argued here, by downloading COVID-19 vaccine caller tunes onto their mobile phones, pharmacists or anyone keen to educate others about the vaccine could help combat disinformation and hesitancy and promote widespread vaccination. To help advance consideration of this approach, the article offers an outline of issues to be considered.

In introducing their argument, the authors point out that existing mobile-phone-based strategies, such as the use of text messaging and direct phone calls, may be too expensive and time consuming for pharmacists to implement in LMICs. Moreover, text messages will have limited efficacy among populations with low literacy. In this context, mobile phone caller tunes, which can be produced in diverse local languages, may be a cost- and time-effective strategy for pharmacists to aid in the promotion of COVID-19 vaccine uptake.

The use of caller tunes to promote health behaviour is not new, even in the context of COVID-19 vaccination promotion. For instance, the United Nations Children's Fund (UNICEF) India has partnered with India's Ministry of Health and Family Welfare to develop caller tunes on COVID-19 vaccination in Hindi. Listeners are advised to trust the vaccine and refrain from believing COVID-19 misinformation. A national helpline is also offered for listeners to call for more information.

Basic considerations for pursuing this approach could include:

• Pharmacists and key content contributors, such as writers, musicians, and actors, collaborate to create short songs or messages on COVID-19 vaccines (i.e., no more than 50 seconds each). In India, mobile phone customers are attracted to the health messages that have the voices of their favorite Bollywood stars. The rest of the developing world could follow India's lead, but with cultural adaptations.
• Studies show that behavioural interventions that are designed with theoretical frameworks, such as the theory of planned behaviour (TPB), are more likely to be effective; Table 3 in the paper highlights key constructs and describes how they could be used to implement caller-tunes-based public health messaging on COVID-19 vaccination.
• Prior to making the tunes available publicly, pilot testing could involve a small non-randomised sample of pharmacists and members of the public providing feedback on the caller tunes regarding their appeal, messaging, and potential effectiveness in convincing vaccine-hesitant people to accept the vaccines.
• Telecommunication companies could accept the tunes to be used as caller tunes on their networks. As part of their corporate social responsibility, these companies should make the caller tunes on COVID-19 vaccines free for activation by customers.
• As mobile phone customers of the telecommunication companies, pharmacists (or anyone keen to educate others about the vaccine) would then be able to activate the caller tunes so that people who call them would hear the COVID-19 vaccine songs or messages.
• Mobile phone customers can choose to have more than one caller tune on their phone at the same time, and they can select which caller should receive which caller tune, allowing for a degree of message targeting (e.g., only play for those who have yet to receive their vaccination or those who express skepticism about COVID-19 vaccines).
• Given that pharmacists in many LMICs were among the first to be vaccinated and are often viewed as trusted sources of information by others in their community, it would be beneficial to have pharmacists' associations encourage their members to put COVID-19 vaccine caller tunes on their personal mobile phones and organisation-issued mobile phones. Pharmacists can use platforms such as WhatsApp groups to mobilise their members to download the caller tunes and encourage other members of the pharmaceutical care team to do likewise.
• As individuals in the general population receive their vaccine, vaccinators could encourage them to install caller tunes on COVID-19 vaccines on their mobile phone. Consistent with the TPB, which highlights the importance of social norms as a key contributor to intention and behaviour, as more and more people add caller tunes to their mobile phone, the message that vaccination is growing within the population will be amplified. To facilitate this process, it might help to consider branding the caller tunes on COVID-19 vaccines.

Other considerations/suggestions:

• The caller tunes should be designed with input from diverse stakeholders. For example, perspectives of pharmacists and members of the public should be sought among those who are vaccine hesitant, those who may favour the vaccines, and those who may have already received their vaccines.
• Pharmacists and creative content creators need to ensure that the caller tunes are culturally appropriate. For example, in most LMICs, considerations of the "common good" or "family" might outweigh "individual autonomy" in decision-making. However, in some regions within the same country, appealing to personal autonomy might be more powerful. Interventions need to be carefully tailored and also avoid positioning social norms as though they are the main driver of people not engaging in the useful behaviour.
• It is possible that public health messaging based on fear could backfire, particularly if not accompanied by strong self-efficacy messages. For example, if COVID-19 vaccines are not widely available in a population, a caller-tunes-based strategy highlighting the dangers of not vaccinating on time may provoke anger because it may not be the fault of people waiting for their vaccines.
• A careful balance between entertainment and educational messaging would need to be established. One study found that humour reduced hesitancy regarding the measles-mumps-rubella (MMR) vaccine, but for parents who were already favourable to vaccination, humorous messages reduced effectiveness relative to non-humorous messages.
• A mix of different strategies should be used in evaluating the effectiveness of the caller tunes. For example, discussions on the caller tunes on social media could be assessed through content analysis, and periodic surveys could be conducted to assess attitudes, beliefs, intentions and behaviours related to COVID-19 vaccines before and after exposure to the caller tunes.

Despite the potential the researchers see in this strategy, they identify some potential limitations and ways to address them:

• Message fatigue: In addition to changing the voice, song, or message to prevent people from tuning them out, the number of times people may hear about it could be reduced.
• Mismatched messaging: A message designed for one region may not be applicable or appropriate for another region even within the same country, so content developers would need to tap local people and consider their culture and social norms when designing caller tunes.
• Lack of favourable conditions for vaccination: Ultimately, easy availability of the COVID-19 vaccine provides the necessary condition for making the caller-tune-based messaging successful.