Evaluation of a Combined Text Messaging and Online Survey Protocol for Giardiasis Case Investigation - Colorado, September 2023-May 2024.

Rapid completion of routine patient interviews by public health practitioners is critical for disease control and prevention efforts; however, increasing numbers of cases of certain diseases, competing priorities, and limited public health resources have made interviewing patients increasingly challenging. The Colorado Department of Public Health and Environment implemented and evaluated a combined text messaging and online survey protocol, with no telephone communication, to collect information from persons with Giardia infections. During September 2023-May 2024, English and Spanish text messages were sent to Colorado residents with laboratory-confirmed Giardia infections reported to the Colorado EpiTrax surveillance system, inviting them to opt in to an online survey. Persons who opted in received a unique survey link via text message. Opt-in and survey completion rates were evaluated by demographic characteristics, data quality, timeliness, and time saved by staff members. Among 305 persons with Giardia who received text messages, 131 (43%) opted in, 95 (73%) of whom completed the survey, for an overall survey completion rate of 31%. The highest survey completion rates were among adults aged 35-54 years (43%), White (34%) and non-Hispanic (33%) respondents, and those who lived in urban areas (32%). The majority (69%) of respondents completed the online survey within 1 day of receipt of the initial text message. In addition, the majority (93%-100%) of respondents answered 11 selected universal questions, and 90%-96% answered potentially sensitive questions (i.e., those on sexual history). The combined text messaging and online survey protocol facilitated more rapid contact with patients and required fewer resources than telephone interviews, saving public health staff members approximately 25 minutes per case and 40 hours overall. The protocol is flexible enough to accommodate shifting priorities and could be used to collect a wide variety of public health information (e.g., for symptom monitoring, contact tracing, and collecting vaccination or health information). Efforts to increase participation might result in higher response rates and improved efficiency and could facilitate an even quicker response.