RESUMEN
Aim of the Study: We aimed to evaluate the virus spreading among a migrant population previously excluded by community surveillance programs. Method(s): We conducted a retrospective study, collecting data about people without SARS-CoV-2-related symptoms who attended the outpatient clinic for undocumented migrants from November 1, 2020, to April 30, 2021. Patients who performed a nasopharyngeal swab and serologic test to evaluate the presence of antibody anti-SARS-CoV-2 were enrolled. Result(s): Overall, 240 people were included in our study. Of them, 15 (6.3%) were female, with a median age of 27.0 years (interquartile range [IQR], 24.3-32.1 years). Thirty-seven patients (15.4%) tested positive for SARS-CoV-2 at the nasopharyngeal swab during the study period. Of these, 16 had positive or low positive results for immunoglobulin G (IgG) and 3 tested positive for both IgG and IgM. Besides, 22 participants (9.2%) resulted positive to serological testing, but negative to polymerase chain reaction testing. The median age of SARS-CoV-2 positive patients (n = 59) was significantly higher than negative (29.6 [IQR, 25.0-35.0] vs 26.8 [IQR, 24.2-31.5], P = 0.022). Among positive patients, the most frequent nationality was Bangladeshi, with 24 people (40.7%, P < 0.001). The highest percentage of positive was found among the same nationality (51.1% of Bangladeshi tested positive). Conclusion(s): Our data underline the significantly higher prevalence of SARS-CoV-2 infection in the undocumented migrant population in respect of the general population of Piacenza province in the same period (15.4% vs 5.9%, P < 0.001). The extension of surveillance programs to the whole population, thus including undocumented people, is crucial to curb the spreading of the virus.Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.