In recent years, honey bee colony losses in the Republic of Kosovo remained largely unknown. From 2019 to 2021, 81 apiaries with different disease suspicions were investigated in the framework of honey bee disease passive surveillance. Fifty-nine of the eighty-one apiaries were tested for Vairimorpha ceranae, Vairimorpha apis, trypanosomatids Lotmaria passim, and Crithidia mellificae. All samples were positive for V. ceranae (100%) whereas L. passim was found with a lower frequency (11.9%). V. apis and C. mellificae were not found. Thirteen of the eighty-one apiaries were tested for seven viruses (ABPV, CBPV, DWV, BQCV, SBV, IAPV, KBV) and five of them were found (ABPV, CBPV, DWV, BQCV, SBV). The most frequently detected viruses in honey bees and Varroa mites were DWV (100%) followed by BQCV, ABPV, SBV, and CBPV (92.3%, 69.2%, 30.8%, and 7.7%, respectively). Varroa mite samples had different degrees of co-infection by viruses. Nine of the eighty-one apiaries consisted of brood combs with larvae, eight of them were AFB positive, ERIC I genotype, and one EFB positive. This paper represents the first molecular investigation (PCR) and detection of the honey bee viruses ABPV, CBPV, DWV, BQCV, and SBV as well as V. ceranae, L. passim, and M. plutonius in the Republic of Kosovo.

American foulbrood (AFB) is one of the most devastating infectious diseases of honey bees with a worldwide distribution. Based on clinical symptoms of AFB, the disease has been thought to have long existed in the Republic of Kosovo honey bee colonies. This passive surveillance study was intended to confirm the presence and determine the distribution of AFB in the Republic of Kosovo, based on the examination of clinical symptoms, rapid immunochromatographic tests, and microbiological and molecular identification of the etiological agent Paenibacillus larvae. From 2007 until 2019, official veterinary inspectors collected 2027 brood combs from a total of 373 apiaries clinically suspected as an AFB outbreak. Samples were collected in 26 out of 38 municipalities of the country predominantly during spring and autumn. P. larvae were isolated from 219 out of 373 apiaries, i.e., 58.71%. All samples with AFB clinical symptoms of the disease were positive in the immunochromatographic test. The presence of the AFB was demonstrated in 24 municipalities. Seventeen positive apiaries from different regions were randomly selected in the years 2016 to 2018 in order to characterize the isolates circulating most recently by ERIC genotyping. The presence of both ERIC I and II genotypes, as well as of a biotype with a profile slightly different from ERIC I and II, was observed. The results indicate a need for a change in approach in future control strategies and training programs for early diagnosis and improved management of apicultural practices.

In this study, we report the first outbreak of highly pathogenic avian influenza (HPAI) A H5N8, clade 2.3.4.4b in Kosovo on 19 May 2021. The outbreak consisted of three phases: May–June 2021, September–November 2021, and January–May 2022. In total, 32 backyards and 10 commercial holdings tested positive for the virus. Interestingly, the third and last phase of the outbreak coincided with the massive H5N1 clade 2.3.4.4b epidemic in Europe. Phylogenetic analyses of 28 viral strains from Kosovo revealed that they were closely related to the H5N8 clade 2.3.4.4.b viruses that had been circulating in Albania, Bulgaria, Croatia, Hungary, and Russia in early 2021. Whole genome sequencing of the 25 and partial sequencing of three H5N8 viruses from Kosovo showed high nucleotide identity, forming a distinctive cluster and suggesting a single introduction. The results of the network analysis were in accordance with the three epidemic waves and suggested that the viral diffusion could have been caused by secondary spreads among farms and/or different introductions of the same virus from wild birds. The persistent circulation of the same virus over a one-year period highlights the potential risk of the virus becoming endemic, especially in settings with non-adequate biosecurity.