Background: There have been concerns regarding COVID-19 testing and estimation of cases and trends.

Objective: To report results from surveillance of COVID-19 among adults in Puerto Rico (PR).

Methods: Automated text message invitations were sent to random phone numbers in Puerto Rico. Since many cases may not have been tested, we also used a published model to categorize probable cases from specific COVID-19 symptoms (loss of smell and taste, severe persistent cough, severe fatigue, and skipped meals). Between November 18, 2020 and February 28, 2021, we sent 644,218 messages; 26.2% were reached, and 3,929 (2.3%) participants answered questions pertaining to last 30 days.

Results: Participants were 21-93 years and represented 97.4% municipalities. Since the lockdown (March 16, 2020), we estimate 6.3% had COVID-19 (2.2% confirmed and 4.1% probable), similar to Puerto Rico Department of Health (PRDH) estimate of 5.7% (2.9% confirmed and 2.8% probable). PREPCOVI total COVID-19 cases were similar for males and females, and higher among people 21-25 and in Caguas region. COVID-19 confirmed and probable cases decreased over time. Confirmed COVID-19 cases in the previous 30 days were 1.7% in November, 1.0% in December, 0.9% in January, and 0.7% in February, although testing remained similar. Test positivity rate was 14.1% in November, 7.4% in December, and 7.3% for January and February.

Conclusion: Since November, COVID-19 has been decreasing in PR despite similar testing rates. Our estimates for probable cases are higher than the PRDH as we included untested cases based on symptoms and we only included adults.