Social insects may accidentally drift into foreign nests due to orientation errors. Even though pathogens have been reported to promote drifting, no data currently exist about the potential impact of titers of the widespread black queen cell virus (BQCV) on the orientation abilities of honey bee workers, Apis mellifera. Here, we investigated titers of BQCV in naturally infected drifted and non-drifted workers. The data show significantly higher virus titers in the drifted workers (Wilcoxon rank sum test, P < 0.01). Our results suggest that high BQCV loads may compromise honey bee orientation, possibly by affecting learning performance similar to other viruses. If future work demonstrates that the correlation found here represents a causal relationship between higher viral titers and drifting, this will be the first identification of clinical symptoms of BQCV in adult honey bee hosts.
