The SARS-CoV-2 virus reached Spain in March 2020, and a nationwide state of alert was declared on March 14th, leading to the confinement of the entire population. The current study was conducted in the Basque Autonomous Community in northern Spain. The authors analyzed stress, anxiety, and depression with the arrival of the virus and the levels of symptoms according to age, comorbidity, and confinement. Levels of anxiety, stress, and depression were measured in a sample of 976 adults, using the DASS scale (Depression Anxiety, and Stress Scale). Although levels of symptoms were generally low at the start of the alert, younger individuals with chronic diseases reported more symptoms than the rest of the population. The study also detected higher levels of symptoms after the stay-at-home order was issued. Such symptoms are predicted to increase as the confinement continues. The authors propose psychological interventions for prevention and treatment in order to mitigate the pandemic's psychological impacts.