[Characteristics of COVID-19 cases and contacts reported in an area of Madrid during beginning of de-escalation.].

Objective: Deescalation began in May 2020 increases social interaction, which has an influence on COVID-19 epidemiological surveillance. The aim of this study was the characterization of COVID-19 cases detected during this period.

Methods: We analyzed certain variables of interest coming from the epidemiological surveys carried out in an area of Madrid during May 2020, and stratified the results depending on its temporal relation with the deescalation. Prevalence for each category of response and average duration in minutes of the telephonic call were calculated. Confidence intervals were estimated at 95%.

Results: We included 167 cases, being 30.5% of them incident and 49.1% prevalent. The main source of infection was home (38.0%; CI 95% 31.4-46.2). Regarding healthcare and social care workers, the main source of infection was workplace (93.0%; 85.4-100). Average number of close contacts per case was 2.0 (1.8-2.2), being 1.5 (1.0-2.0) among pre-deescalation incident cases and 2.4 (1.8-3.0) among those post-deescalation. Average duration of each survey was 35.9 minutes (32.2-38.9), being 32.1 (24.4-39.8) among pre-deescalation incident cases and 37.0 (29.6-44.4) among those post-deescalation. Most of the contacts were household, both before and after beginning of deescalation.

Conclusions: Home is the most prevalent place for the acquisition of the infection among general population, while workplace is the most prevalent among healthcare and social care workers. The initial phase of deescalation do not represents a change regarding sources of infection, but it may increase the number of close contacts.