# First Molecular Detection and Characterization of Nosema ceranae in Honey Bees (Apis mellifera) from the Northern Highlands of Ecuador

## TL;DR

This study confirms the presence of Nosema ceranae in Ecuadorian honey bees, highlighting its potential impact on bee health and food security.

## Contribution

The first molecular detection and characterization of Nosema ceranae in Ecuadorian honey bees using phylogenetic analysis.

## Key findings

- Nosema ceranae was detected in 21.34% of honey bee samples from northern Ecuador.
- Ecuadorian N. ceranae is phylogenetically similar to strains from Argentina and Brazil.
- This is the first molecular confirmation of N. ceranae in Ecuador.

## Abstract

Bees play a key role in agriculture and the environment since they pollinate many plants that provide food for people and animals. However, their health can be affected by microscopic parasites that cause diseases and weaken colonies. In Ecuador, little is known about which of these parasites are affecting honey bees. This study investigated the presence of two species of Nosema, a group of tiny organisms that infect bees and can reduce honey production and colony survival. Samples were collected from different provinces in the northern region of the country, and laboratory tests showed that both species, Nosema apis and Nosema ceranae, are present in Ecuador. The second species was found more frequently and is closely related to those found in other South American countries. This is the first report confirming the presence of both Nosema species in Ecuador. These findings have implications for food security and environmental sustainability.

The development of beekeeping in Ecuador has generated the need to strengthen the bee health program. Research on the main pathogens responsible for diseases like nosemosis, which can severely impact bee health, is of special interest. This study aims to identify the Nosema apis and/or Nosema ceranae species infecting honey bee colonies located in the northern Andean region of Ecuador using multiplex PCR targeting the RNA polymerase II gene (RPB1), and the phylogenetic analysis of N. ceranae based on the 16 S rRNA gene sequences. Among the 164 honey bee samples collected from colonies in the provinces of Carchi, Imbabura, and Pichincha, the prevalence of Nosema apis and Nosema ceranae was 14.63% and 21.34%, respectively. Phylogenetic analysis showed that N. ceranae from Ecuador is closely related to the sequences from Argentina and Brazil. These findings provide the first molecular confirmation of N. ceranae in Ecuador and support the need for molecular monitoring of honey bee pathogens in the region.