Nosema ceranae an emergent pathogen of Apis mellifera in Chile

Abstract

The microsporidian Nosema apis and Nosema ceranae have been associated with colony disorders of Apis mellifera and Apis cerana, respectively. N. apis is endemic in South America. Recently, N. ceranae has been detected in Brazil, Uruguay and Argentina. No report of its presence, distribution and prevalence in Chile is available. Here, we present a real-time PCR-based method that was able to discriminate between N. apis and N. ceranae. The dynamic range of this assay was 100 to 100,000 spores per honeybee. False-negative results were avoided due to the use of ACTIN gene as internal standard. False-positive results were obtained neither in experimentally nor in naturally contaminated samples. Using this method, we screened 240 beehives from the Chilean region where 42% of the total country honey production take places (Región del Biobío). Nosema spp. were detected in the four provinces and in 20 of the 26 communes of the region. Among the samples analysed, 49% were positive for N. ceranae. Their infection level ranged from 200 to more than 100,000 spores per honeybee. N. apis was not detected in this region. Hence, our data show that in Chile N. ceranae is an emergent pathogen that is been replacing N. apis. Also, they support that N. ceranae maybe the actual responsible for nosemosis in A. mellifera in South America.

Prevalence and phylogenetic analysis of honey bee viruses in the Biobío Region of Chile and their association with other honey bee pathogens

“…Although it has been described as an adult bee parasite (Higes et al, 2008;Forsgren and Fries, 2010), this microsporidia was also found in pupae, probably due to spore contamination from nurse bees, which have been described as carriers of this parasite (Meana et al, 2010) or through feeding with contaminated pollen (Higes et al, 2008). Other studies carried out in the spring of 2010 and summer of 2011 in the same region revealed that N. ceranae is widely distributed in the region (Martínez et al, 2012). However, in the present study we only detected N. ceranae in 18% of the analyzed apiaries.…”

Honeybee health in South America

“…For example, 49 % of Nosema prevalence was reported in 2012 from the Bio-Bio Region, (Martínez et al 2012). Later, 100 % of the prevalence in samples from 12 apiaries in the Valparaíso Region without mixed infection with N. apis was reported (Bravo et al 2014 Valparaiso.…”

Identification of Nosema ceranae in the Valparaíso District, Chile

“…Moreover, Martínez et al (2012) identified the presence of N. ceranae in Chile only in the Bío-Bío District, which covers 42.0% of the country's honey production. The study evaluated four provinces of the Valparaíso District, obtaining information from a total of 26 communities and 49.0% of them showed the presence of N. ceranae.…”