Endemic Circulation of Cluster 19 African Swine Fever Virus in Serbia and Bosnia and Herzegovina

African swine fever (ASF) is a highly fatal viral disease of domestic pigs and wild boar that continues to threaten pig production across Europe. Genotype II African swine fever virus (ASFV) has been present in Serbia since 2019 and was first confirmed in Bosnia and Herzegovina in 2023, yet recent genetic data from the region have been lacking. This study aimed to update the genetic characterization of ASFV strains circulating in Serbia between 2023 and 2025 and to provide the first sequence data from Bosnia and Herzegovina. A total of 110 isolates were analyzed by partial sequencing of seven genomic regions recommended by the European Union Reference Laboratory. Good-quality sequences were obtained for at least two loci per isolate. All isolates belonged to genotype II and were classified as CVR variant I, IGR-II, O174L-I, MGF I, K145R-I, and ECO2-II, corresponding to cluster 19. No novel genetic changes were identified in the sequenced fragments. These findings indicate the stable, endemic circulation of cluster 19 in both domestic pigs and wild boar, maintained through ecological and human-mediated transmission at the wildlife-livestock interface. The detection of cluster 19 in Bosnia and Herzegovina underscores transboundary spread and highlights the need for continued molecular surveillance and regional cooperation.