Measuring the effectiveness of an automated text messaging active surveillance system for COVID-19 in the south of Ireland, March to April 2020.

We report the effectiveness of automated text messaging for active surveillance of asymptomatic close contacts of coronavirus disease (COVID-19) cases in the Cork/Kerry region of Ireland. In the first 7 weeks of the COVID-19 outbreak, 1,336 close contacts received 12,421 automated texts. Overall, 120 contacts (9.