On March 11, 2020, the World Health Organization declared the COVID-19 pandemic and issued a series of recommendations for countries to activate and expand their emergency response mechanisms. Faced with the WHO recommendations and the increase in cases in Colombia, the Ministry of Health and Social Protection declared the start of the mitigation phase of the epidemic on March 31, 2020. The National Institute of Health, through its departmental and district health secretaries, has adapted a public health surveillance system for COVID-19 at the community level, to identify new cases and follow-up contacts, to determine areas risk groups or conglomerates that allow health authorities to take measures to control transmission chains. Timely capture and laboratory diagnostic confirmation of probable cases, achieving their self-isolation, identification and tracing of their contacts, leads to an effective reproduction number equal to or less than one, as an alternative to mass testing and quarantine. Case investigation and contact tracing effort are a very common tool in public health. These measures protect the health of people, because if you can restrict contact between infected people and others, you can limit the transmission of SARS-CoV-2; thus, this strategy allows to maintain control of each outbreak that is detected in time.