Introduction: SARS-CoV-2 viruses are circular single-stranded, RNA viruses with a genome size between 26 kb and 32 kb. Coronaviruses are a diverse group of respiratory viruses, classified into four genera that include α-, β-, γ-, and δ-coronaviruses. The SARS-CoV-2 virus causes, depending on the type of virus, fever, dry cough, fatigue, shortness of breath, muscle pain, pneumonia. Transmission of SARS-CoV-2 virus occurs mainly by inhalation of respiratory droplets or aerosols when sneezing, breathing or coughing of infected persons in the vicinity of healthy persons. The time between exposure to the virus and the appearance of the first symptoms is between 2 and 14 days, and a person is most contagious when he has severe symptoms of the disease, but also up to 2 days before the onset of symptoms. Objectives: The objectives of this study were to diagnose the SARS-CoV-2 virus in the samples taken, to show its prevalence in the Split and Dalmatia County and to compare the data with data in the Republic of Croatia and the world. Materials and methods: The method used to detect SARS-CoV-2 virus is RealTime PCR where a nasopharyngeal / pharyngeal swab is used as a sample. Nucleic acid detection by PCR is a non-invasive method of detecting SARS-CoV-2 virus. Results: During the period of 1 year (June 1, 2020 – May 31, 2021), a total od 179,932 samples were tested for SARS-CoV-2 virus at the Institute of Public Health of Split and Dalmatia Country, of which 40,727 (26.6 %) samples were positive. Conclusions: SARS-CoV-2 is the third highly pathogenic human coronavirus disease to date, which, with its rapid spread, is the most serious threat to global health in this century. By implementing primary (vaccination) and secondary prevention measures (adherence to public health measures), the SARS-CoV-2 virus should be significantly reduced and even eliminated in the future.