Molecular detection of Black queen cell virus and Nosema in apiaries of Alborz, Tehran and Mazandaran provinces.

Black queen cell virus (BQCV) is a viral pathogen in bees that causes significant losses in bees. The virus causes the cell wall of the queen to changes from dark brown to black. In the cells, the queen larva dies due to disease and the body fills with virus particles during pupation or pre-pupation. Sampling of 154 apiaries located in 3 provinces of the country were done in cooperation with the Veterinary Organization. About 100 adult bees were sampled from each apiary and sent to the Honey bee, Silkworm and Wildlife diseases Department of Razi Vaccine and Serum Research Institute. Samples were first examined microscopically for Nosema and then RNA extraction and reverse polymerase chain reaction (RT-PCR) were performed. The PCR product was electrophoresed and bands with a length of 477 bp were observed. Out of 154 apiaries, in 70 apiaries (45.45% and 95% confidence interval equal to 53.66% - 37.42%) queen cell blackening virus, in 25 apiaries (23.16% and 95% confidence interval equal to 23.02% - 10.8%) and in 9 apiaries, both (5.8% and 95% confidence interval equal to 10.8% - 2.7%) were identified.Thus, according to the worker bees are important reservoirs for the virus accumulates in bee colonies and can be a potential threat to the queen neonatal population, but no significant relationship was observed between the presence of Nosema and BQCV infection in this study.