Abstract
Nosemosis, caused by microsporidians of the genus Vairimorpha, is one of the most significant diseases affecting the honey bee Apis mellifera L. (Apidae: Hymenoptera), with negative impacts on its health and productivity. This study aimed to assess the presence of Vairimorpha ceranae in apiaries from the state of Campeche, Mexico. Honey bee samples were collected from 79 colonies across 29 apiaries, and DNA was extracted for analysis. Detection of the microsporidian parasite was achieved through amplification of the 16S small subunit ribosomal RNA gene by PCR and PAGE, revealing a high prevalence of Vairimorpha ceranae. The results represent the first confirmed record of Vairimorpha ceranae in this region, with widespread infection detected among sampled colonies. This finding is crucial for identifying the frequency and geographic distribution of this parasite in Mexico and will support the development of targeted management and control strategies adapted to local conditions, ultimately contributing to the conservation and health of honey bee populations in Campeche.