[Epidemiological data on HIV/AIDS and the surveillance system in the Czech Republic].

Human immunodeficiency virus (HIV) progressively impairs immune function. If the infection is detected late or left untreated, it leads to the development of AIDS. Therefore, from a public health perspective, it is necessary to monitor the occurrence of infection in the population, as well as trends overall and in specific subgroups. This is achieved through a national HIV surveillance system, whose outputs can be used not only to describe the epidemiological situation but also to guide preventive activities. The text outlines the organizational components of the surveillance system developed since 1986 and presents the key epidemiological data describing the HIV epidemic in the Czech Republic. Between 1985 and 2024, a total of 4888 cases of HIV infection were detected among Czech citizens and foreigners with long-term or permanent residence. Of those, 926 were diagnosed with AIDS, and 654 died. The basic characteristics of the HIV epidemic in the Czech Republic are the predominance of sexual transmission, especially among men who have sex with men, but with increasing numbers of heterosexually transmitted infections, a low proportion of women (approximately 15%), and an increasing proportion of foreigners (48% in the last five years). The annual number of new cases initially hovered around a few dozen, then steadily increased from 2003 until reaching 286 in 2016. After a slight decline, the numbers peaked at 292 in 2022. Recent trends have been affected by the COVID-19 pandemic and the war in Ukraine. In addition to the above figures, 856 HIV-positive refugees from Ukraine were registered in 2022-2024. Despite these facts, the Czech Republic continues to be classified as a low-prevalence country in both the European and global contexts. However, the trend in recent years has not been favorable, with the number of new cases showing a slight increase. Keywords: HIV, AIDS, surveillance, HIV transmission, foreigners.