Bee disease a mystery

Jun 30, 2008

Scientists are one step closer to understanding the recent demise of billions of honey bees after making an important discovery about the transmission of a common bee virus. Deformed wing virus (DWV) is passed between adult bees and to their developing brood by a parasitic mite called Varroa destructor when it feeds.

However, research published in the July issue of the Journal of General Virology suggests that the virus does not replicate in Varroa, highlighting the need for further investigation.

Deformed wing virus has been linked to the collapse of honey bee colonies in Britain. In recent years the prevalence of the virus has increased globally in colonies infested with Varroa. It is widely accepted that the virus replicates in the mite and is then transmitted to bees when it bites.

However, researchers at Rothamsted Research and the University of Nottingham have found that the virus does not replicate in the mite, suggesting an alternative means of transmission.

"Experiments and field observations have shown that V. destructor is able to transmit several different unrelated honey bee viruses, like acute bee paralysis virus and Kashmir bee virus as well as deformed wing virus," said Professor Teresa Santillan-Galicia from Rothamsted Research. "But we still don't know exactly how these viruses are passed from the mite to the bee."

The researchers wanted to find out whether the virus replicates in the mite and if so where this occurs, to understand how the virus is transmitted. They used a process called immunohistochemistry which involves using antibodies which bind to specific surface proteins, enabling the virus particles to be located. There was no evidence of virus replication within the cells of the mite; the virus was found only in the lumen of the gut, suggesting it was merely eaten.

"The presence of deformed wing virus in large amounts in mite faeces suggests it is picked up during feeding on an infected bee," said Professor Santillan-Galicia. "However, one important question remains – how is the virus transmitted to bees?"

One possibility is that the mouthparts of the mite could become contaminated with the virus during feeding, but this is an unlikely answer. Varroa mites cannot regurgitate their gut contents as there is a membrane in the oesophagus that acts as a non-return valve, so they could not pass the virus on this way either. Unfortunately, not enough is known about the anatomy of the mite, or their feeding mechanism, to suggest other routes of transmission.

"It is likely that the amount of virus acquired by the mite plays an important role in the interaction between deformed wing virus and the Varroa mite," said Professor Santillan-Galicia. "Full understanding of the interaction between deformed wing virus and the Varroa mite will provide basic information for the future development of more sustainable control strategies against the mite and the virus. Our work provides elements of understanding but further research in this area is needed."

Source: Society for General Microbiology

Explore further: Aging white lion euthanized at Ohio zoo

add to favorites email to friend print save as pdf

Related Stories

Australia's biosecurity may be shocked

Nov 25, 2014

A human disease pandemic, European honey bee colonies wiped out and an invasion of a devastating wheat disease are just three potential biosecurity threats facing Australia, according to a report released today.

Can stress management help save honeybees?

Nov 24, 2014

Honeybee populations are clearly under stress—from the parasitic Varroa mite, insecticides, and a host of other factors—but it's been difficult to pinpoint any one of them as the root cause of devast ...

Of bees, mites, and viruses

Aug 21, 2014

Honeybee colonies are dying at alarming rates worldwide. A variety of factors have been proposed to explain their decline, but the exact cause—and how bees can be saved—remains unclear. An article published on August ...

Best for bees to be stay-at-homes

Jul 14, 2014

Honey bees with roots in the local environment manage much better in the struggle for survival than imported honey bees from foreign environments.

Parasite-free honey bees enable study of bee health

Jul 01, 2014

An international team of researchers has discovered honey bee colonies in Newfoundland, Canada, that are free of the invasive parasites that affect honey bees elsewhere in the world. The populations offer ...

Recommended for you

A vegetarian carnivorous plant

Dec 19, 2014

Carnivorous plants catch and digest tiny animals in order and derive benefits for their nutrition. Interestingly the trend towards vegetarianism seems to overcome carnivorous plants as well. The aquatic carnivorous bladderwort, ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

gmurphy
5 / 5 (1) Jun 30, 2008
I hope they get this asap. It's stunning to see how dependent we are on the little critters.
thales
4 / 5 (1) Jun 30, 2008
Yeah, but maybe the mite serves a purpose that helps the bees in some way as well. I agree, it's scary to think billions have been killed. I wonder what kind of impact that has already had on agricultural commodity prices.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.