Israeli Acute Paralysis Virus: Epidemiology, Pathogenesis and Implications for Honey Bee Health

Among numerous viruses that infect honey bees (Apis mellifera), Israeli acute paralysis virus (IAPV) can be linked to severe honey bee health problems. Breeding for virus resistance may improve honey bee health. To evaluate the potential for this approach, we compared the survival of IAPV infection among stocks from the U.S. We complemented the survival analysis with a survey of existing viruses in these stocks and assessing constitutive and induced expression of immune genes. Worker offspring from selected queens in a common apiary were inoculated with IAPV by topical applications after emergence to assess subsequent survival. Differences among stocks were small compared to variation within stocks, indicating the potential for improving honey bee survival of virus infections in all stocks. A positive relation between worker survival and virus load among stocks further suggested that honey bees may be able to adapt to better cope with viruses, while our molecular studies indicate that toll-6 may be related to survival differences among virus-infected worker bees. Together, these findings highlight the importance of viruses in queen breeding operations and provide a promising starting point for the quest to improve honey bee health by selectively breeding stock to be better able to survive virus infections.

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Nationwide Screening for Bee Viruses and Parasites in Belgian Honey Bees

Viruses ◽

10.3390/v12080890 ◽

2020 ◽

Vol 12 (8) ◽

pp. 890

Author(s):

Severine Matthijs ◽

Valérie De Waele ◽

Valerie Vandenberge ◽

Bénédicte Verhoeven ◽

Jacqueline Evers ◽

...

Keyword(s):

Viral Load ◽

Real Time ◽

Honey Bee ◽

Honey Bees ◽

High Viral Load ◽

Deformed Wing Virus ◽

Bee Health ◽

Honey Bee Health ◽

Varroa Mites ◽

Paralysis Virus

The health of honey bees is threatened by multiple factors, including viruses and parasites. We screened 557 honey bee (Apis mellifera) colonies from 155 beekeepers distributed all over Belgium to determine the prevalence of seven widespread viruses and two parasites (Varroa sp. and Nosema sp.). Deformed wing virus B (DWV-B), black queen cell virus (BQCV), and sacbrood virus (SBV) were highly prevalent and detected by real-time RT-PCR in more than 95% of the colonies. Acute bee paralysis virus (ABPV), chronic bee paralysis virus (CBPV) and deformed wing virus A (DWV-A) were prevalent to a lower extent (between 18 and 29%). Most viruses were only present at low or moderate viral loads. Nevertheless, about 50% of the colonies harbored at least one virus at high viral load (>107 genome copies/bee). Varroa mites and Nosema sp. were found in 81.5% and 59.7% of the honey bee colonies, respectively, and all Nosema were identified as Nosema ceranae by real time PCR. Interestingly, we found a significant correlation between the number of Varroa mites and DWV-B viral load. To determine the combined effect of these and other factors on honey bee health in Belgium, a follow up of colonies over multiple years is necessary.

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Prevalence of common honey bee pathogens at selected apiaries in Kenya, 2013/2014

International Journal of Tropical Insect Science ◽

10.1017/s1742758417000212 ◽

2017 ◽

Vol 38 (01) ◽

pp. 58-70 ◽

Cited By ~ 6

Author(s):

Juliette R. Ongus ◽

Ayuka T. Fombong ◽

Janet Irungu ◽

Daniel Masiga ◽

Suresh Raina

Keyword(s):

Honey Bee ◽

Disease Surveillance ◽

Deformed Wing Virus ◽

Bee Health ◽

Queen Cell ◽

Honey Bee Health ◽

Kashmir Bee Virus ◽

Bee Disease ◽

Acute Bee Paralysis Virus ◽

Paralysis Virus

AbstractThe present study was part of a larger surveillance effort to identify the determinants of African honey bee health, and, particularly, to detect honey bee pathogens across Kenya, where 160 colonies were examined from 32 apiaries (five colonies/apiary). From each colony, 20 individual foragers, nurse bees, worker pupae, and drone pupae were sampled separately. These were organized as 30 foragers, 32 nurse bees, 28 worker pupae, and 10 drone pupae pools. Nucleic acid was extracted from the pooled homogenates and tested using a panel of 18 different (RT-)PCR methods targeted at detectingPaenibacillus larvae,Melissococcus plutonius,Ascophaera apis,Aspergillusspp.,Nosema ceranae, N. apis,Deformed wing virus(DWV),Varroa destructor virus 1(VDV 1),Acute bee paralysis virus(ABPV),Sacbrood virus(SBV),Israeli acute paralysis virus(IAPV),Black queen cell virus(BQCV),Chronic bee paralysis virus(CBPV), andKashmir bee virus. All amplified bands were sequenced and compared to the GenBank database. VDV 1 was the most abundant virus at 50% prevalence in the 100 bee pools. It was closely followed by DWV at 44%. The others were BQCV (36%), SBV (14%), IAPV (9%), ABPV (8%), andN. ceranae(5%). The pathogens co-existed within apiaries. VDV 1 was present in 66% of the apiaries, DWV in 69%, BQCV in 69%, SBV in 28%, IAPV in 22%, ABPV in 19%, andN. ceranaein 13%. The study concludes that these pathogens should be incorporated in honey bee disease surveillance activities in the region.

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Impact of Chronic Exposure to Sublethal Doses of Glyphosate on Honey Bee Immunity, Gut Microbiota and Infection by Pathogens

Microorganisms ◽

10.3390/microorganisms9040845 ◽

2021 ◽

Vol 9 (4) ◽

pp. 845

Author(s):

Loreley Castelli ◽

Sofía Balbuena ◽

Belén Branchiccela ◽

Pablo Zunino ◽

Joanito Liberti ◽

...

Keyword(s):

Gut Microbiota ◽

Honey Bee ◽

Chronic Exposure ◽

Pollination Services ◽

Deformed Wing Virus ◽

Immune Genes ◽

Bee Health ◽

Honey Bee Health ◽

Sublethal Doses ◽

The Impact

Glyphosate is the most used pesticide around the world. Although different studies have evidenced its negative effect on honey bees, including detrimental impacts on behavior, cognitive, sensory and developmental abilities, its use continues to grow. Recent studies have shown that it also alters the composition of the honey bee gut microbiota. In this study we explored the impact of chronic exposure to sublethal doses of glyphosate on the honey bee gut microbiota and its effects on the immune response, infection by Nosema ceranae and Deformed wing virus (DWV) and honey bee survival. Glyphosate combined with N. ceranae infection altered the structure and composition of the honey bee gut microbiota, for example by decreasing the relative abundance of the core members Snodgrassella alvi and Lactobacillus apis. Glyphosate increased the expression of some immune genes, possibly representing a physiological response to mitigate its negative effects. However, this response was not sufficient to maintain honey bee health, as glyphosate promoted the replication of DWV and decreased the expression of vitellogenin, which were accompanied by a reduced life span. Infection by N. ceranae also alters honey bee immunity although no synergistic effect with glyphosate was observed. These results corroborate previous findings suggesting deleterious effects of widespread use of glyphosate on honey bee health, and they contribute to elucidate the physiological mechanisms underlying a global decline of pollination services.

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