Honey as an eDNA Reservoir: Detecting Spiroplasma apis and Spiroplasma melliferum in Australian honey bee populations

Spiroplasma apis and Spiroplasma melliferum are often overlooked pathogens that harm honey bee health. This study used environmental DNA (eDNA) from honey to identify these pathogens. We amplified DNA from 135 honey samples across Australia using Spiroplasma-specific PCR primers. The results revealed a high prevalence of S. melliferum (70%) across Australia, in contrast to S. apis, which was detected in 13% of samples. The findings indicate that S. melliferum is widespread in Australia, potentially threatening honey bee health. We present the first phylogenetic analysis of Australian Spiroplasma apis and Spiroplasma melliferum isolates, with Spiroplasma apis showing high similarity with reference strains from the USA, Belgium, and Taiwan, whereas Spiroplasma melliferum displays broader genetic diversity.