Reliability of Morphological and PCR Methods for the Official Diagnosis of Aethina tumida (Coleoptera: Nitidulidae): A European Inter-Laboratory Comparison.

The Small Hive Beetle ( Murray, 1867) is an invasive scavenger of honeybees. Originally endemic in sub-Saharan Africa, it is regulated internationally in order to preserve the areas still free from this species. To ensure the reliability of official diagnoses in case of introduction, an inter-laboratory comparison was organised on the identification of by morphology and real-time PCR. Twenty-two National Reference Laboratories in Europe participated in the study and analysed 12 samples with adult coleopterans and insect larvae. The performance of the laboratories was evaluated in terms of sensitivity and specificity. Sensitivity was satisfactory for all the participants and both types of methods, thus fully meeting the diagnostic challenge of confirming all truly positive cases as positive. Two participants encountered specificity problems. For one, the anomaly was minor whereas, for the other, the issues concerned a larger number of results, especially real-time PCR, which probably were related to inexperience with this technique. The comparison demonstrated the reliability of official diagnosis, including the entire analytical process of identification: from the first step of the analysis to the expression of opinions. The performed diagnostic tools, in parallel with field surveillance, are essential to managing introduction.