Since the outbreak of atypical pneumonia cases in the Wuhan region, China, in late 2019, the virus causing what is now called COVID-19 has rapidly spread around the globe. As of late May 2020, more than 5.5 million people have been infected and almost 350 000 have died. The first case of infection in Croatia was identified on February 25, 2020 (https://www.hzjz.hr/priopcenja-mediji/covid-19-priopcenje-prvog-slucaja/), and the current number of confirmed infected patients is 2244, with 100 deaths. The National Civil Protection Directorate promptly implemented strict measures to limit the virus transmission, which have decreased the number of daily new cases from almost 100 at the peak of the epidemic to below 10. Bringing the epidemic under control, which means that the basic reproduction number (R0 ) is below 1, transmission is controlled, and there is an ample number of beds and respirators available in hospitals, created the conditions for the restrictions to be eased. Although this has brought relief to the population and the hard-hit economy, it is impossible to predict further developments beyond the devastating effect on the economy. The efforts of countless laboratories around the world have resulted in an unprecedented accumulation of knowledge on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Yet, many aspects of the virus biology, transmission, and treatment remain elusive.