Is Acarapis woodi a single species? A new PCR protocol to evaluate its prevalence

Abstract

Acarapisosis is a disease of the adult honey bee Apis mellifera L., caused by the tracheal mite Acarapis woodi (Rennie), that affects the prothoracic tracheas of worker honey bees. Although it is not usually considered a real problem for honey bee colonies in southern Europe (mainly Spain and Greece), where the majority of professional beekeepers are located in Europe, recent works have reported the constant presence of this mite in this area, making it a potential cofactor for colony losses. In this study, we developed a specific PCR diagnostic tool that improves the techniques used so far and allowed us to confirm the presence of this parasite in Spain, urging the need to monitor its prevalence and implications in the health of the colonies. Indeed, in a total of 635 apiaries analysed, the prevalence of A. woodi in 2010 was 8.3 and 4 % in 2011. The mite is present in bee colonies over time and should not be underestimated as a possible cofactor in the collapse of bee colonies. Additionally, some positive samples were cloned so a genetic analysis on the diversity within A. woodi isolates was also approached. This allowed us to identify different genetic variants within an isolate, even when they were present at low frequencies. And this genetic analysis revealed the existence of a different clade of Acarapis sequences that could represent a new species or subspecies, although more research is required to verify the identity of this novel lineage at genetic and morphological level.

Effects of parasites and pathogens on bee cognition

“…Crithidia bombi parasitises different bumblebees species and can reduce their reproductive ability and life span (Brown et al, 2003;Otti & Schmid-Hempel, 2008). Crithidia mellificae and Lotmaria passim are highly prevalent in honey bee colonies (Ravoet et al, 2013;Cepero et al, 2014); however, their pathogenicity is still poorly documented (Schwarz & Evans, 2013;Higes et al, 2016;Stevanovic et al, 2016).…”

“…DWV) which can further reduce the life span of workers and potentially cause colony collapse. Other mites such as Acarapis woodi also infect honey bee colonies but rarely lead to colony collapse (Cepero et al, 2015).…”

Current Status of Loop-Mediated Isothermal Amplification Technologies for the Detection of Honey Bee Pathogens

“…The most common technique for detecting honey bee pests and pathogens is by quantitative PCR (qPCR), and in the case of a virus, this requires the use of reverse transcriptase to amplify the RNA, which is termed RT-qPCR. There are many individual qPCR assays to detect specific pathogens, such as P. larvae (16), M. plutonis (17), A. woodi (18), Nosema spp. (19).…”

Estudio preliminar sobre la presencia de enfermedades en enjambres de abejas africanizadas (Apis mellifera) en diferentes zonas de Costa Rica

“…Acariosis: Padecimiento provocado por el ácaro Acarapis woodi, el cual es un parásito microscópico que afecta únicamente a las abejas adultas, parasitando la parte pro-torácica de la tráquea (Cepero et al 2015). Este ácaro perfora las paredes de la tráquea y se alimenta de la hemolinfa (Delmiglio et al 2015).…”

“…Su efecto patógeno en las abejas individuales depende del número de parásitos dentro de la tráquea (Sakamoto et al 2017). Por tanto, los signos clínicos de la acariosis son evidentes con niveles de infección elevados (De Jong 1997;Cepero et al 2015). Algunos síntomas que podrían relacionarse con acariosis son abejas con las alas distendidas, abanicándolas sin poder volar, abejas muertas o moribundas en frente de la colmena, entre otros (Bailey & Ball 1991;Ritter 2001).…”