Nosema ceranae in Apis mellifera: a 12 years postdetection perspective

Abstract

Nosema ceranae is a hot topic in honey bee health as reflected by numerous papers published every year. This review presents an update of the knowledge generated in the last 12 years in the field of N. ceranae research, addressing the routes of transmission, population structure and genetic diversity. This includes description of how the infection modifies the honey bee's metabolism, the immune response and other vital functions. The effects on individual honey bees will have a direct impact on the colony by leading to losses in the adult's population. The absence of clear clinical signs could keep the infection unnoticed by the beekeeper for long periods. The influence of the environmental conditions, beekeeping practices, bee genetics and the interaction with pesticides and other pathogens will have a direct influence on the prognosis of the disease. This review is approached from the point of view of the Mediterranean countries where the professional beekeeping has a high representation and where this pathogen is reported as an important threat.

Screening of Differentially Expressed Microsporidia Genes from Nosema ceranae Infected Honey Bees by Suppression Subtractive Hybridization

“…From 2004From to 2006, N. ceranae infections were detected in A. mellifera in Taiwan and European countries [14,15]. Hereafter, the prevalence of N. ceranae was confirmed in the population of A. mellifera, and has become a globally distributed bee pathogen in this past decade [16]. N. ceranae coincided with early reports of CCD, and was suggested to be a factor in honey bee declines [5].…”

“…It affects adult bees and was recently found in collapsing A. mellifera colonies in Spain [17]. Experimental results suggest that N. ceranae is more virulent than N. apis; therefore, N. ceranae is considered to be an important bee pathogen that causes bee colony loss [16].…”

“…However, it is not easy for beekeepers to note N. ceranae infection in honey bee colonies due to the lack of obvious symptoms from latent infection of N. ceranae. Ignorance of latent infection of N. ceranae might raise the risk of long-term colony infection of N. ceranae, and then cause colony disease outbreaks [16]. Therefore, early detection of nosemosis at the latent infection stage is needed for management of honey bee colonies.…”

Infectivity and virulence of Nosema ceranae (Microsporidia) isolates obtained from various Apis mellifera morphotypes

“…Whether N. ceranae is virulent to all Apidae and whether it is equally virulent to every A. mellifera subspecies is unclear. What is clear, is that the current N. ceranae geographical range covers a large portion of the A. mellifera diversity, with possibly 14 subspecies of the four major evolutionary lineages as putative hosts (Martín‐Hernández et al, 2018). The effect of N. ceranae infections on colony health and survival is not entirely clear (Higes et al, 2008; Genersch 2010; Gisder et al, 2010; Guzman Novoa et al, 2011; Stevanovic et al, 2011; Fernández et al, 2012).…”

Transcriptional and physiological responses of hypopharyngeal glands in honeybees (Apis mellifera L.) infected by Nosema ceranae

“…The HPGs of infected bees exhibited a lower protein content and a higher amylase activity, indicating that Nosema -infected nurse bees underwent pronounced changes in the hypopharyngeal gland function, and these physiological alterations may be closely related to those upregulated genes in HPGs of infected bees. In addition, N. ceranae infection poses nutritional and energetic stress to bees (Martín-Hernández et al 2018), and therefore, HPG degradation is probably more active in Nosema -infected bees with smaller HPGs (Alaux et al 2010), resulting in the large number of upregulated genes in Nosema -infected undernourished bees (Corby-Harris et al 2016).…”