# I – Introduction

In the early months of the COVID-19 pandemic, health authorities around the world scrambled to inform the public about how to reduce the risk of infection. Modes of message-sending varied substantially depending on local contexts, and multi-mode campaigns were common. Television announcements and dedicated news segments were widely used, complemented where feasible by smartphone alerts, radio broadcasts, social media services, newspaper reports, and even personal appeals from health care workers.

With more than 5 billion unique mobile phone subscribers in the world,<sup>2</sup> COVID-19 information campaigns also turned to short message service (SMS) text messages in many countries. A standardized message bank for these initiatives was quickly developed and prompted by the World Health Organization and other international organizations.<sup>3</sup> The text messaging approach had several key strengths, especially in reaching out to geographically disperse populations, and in low and middleincome countries where advanced smartphone penetration remained limited. In such situations (i.e. large numbers of both smartphone and basic mobile phone users) text messaging was often the “lowest common denominator” to reach the maximum audience. These constraints were highly relevant to the setting of this study. Data from the Listening to Tajikistan survey shows that before the outbreak, mobile phone coverage was quite high, with about 95 percent of the population reporting access to at least one mobile phone in their immediate household (and 108 connections per 100 people in 2019 according the GSMA industry association). However, the number of _mobile internet connections,_ which are required for most smartphone functions and social media applications, was much lower, standing at just 55 connections per 100 people in 2019 according to the same source.

Designs for SMS-based COVID-19 messaging campaigns have been widely documented since the start of the pandemic. Details of campaigns in the United Kingdom,<sup>4</sup> Taiwan, China (Huang, 2020), Saudi Arabia (Hassounah, Hafsa, and Mohammed Alhefzi, 2020), Brazil (Rico et. al., 2020), Kenya (Austrian et. al., 2020) and Denmark are only a small sample.<sup>5</sup> However, evidence for the efficacy of these programs is more fragmented, and in the few cases where systems have been evaluated, results have been mixed thus far. For instance, in a large randomized control trial in Denmark, Falco and Zaccagni (2020) found that text message reminders to social distance did not appear to have had any impact on individual actions in that setting. Austrian et. al (2020) however, found that SMS messages on COVID-19 from Kenya’s government were among the most trusted sources of information on the pandemic and risk reduction behaviors among the population there.

Text messages have also been shown to be highly effective in other public health contexts. For instance, a systematic meta-analysis by Mekonnen et al. (2019) found substantial improvements with

> 2 Live tracking application available at this link

> 3 The official message bank is available at this link

> 4 <u>Link</u> to government website

> 5 <u>Link</u> to newspaper article

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