Grounded. a bumblebee with Deformed Wing Virus from a study conducted in 06.
Elke Genersch
honey bees are apparently Typhoid Marys of the world pollinator. One study suggests that bees spread two kinds of pathogens to wild bumblebees. And one of them, the virus deformed wing (DWV), kills bees across the UK may have contributed to the decline of wild populations of the nation. The high occurrence of DWV is "truly alarming", said Peter Neumann molecular ecologist at the University of Berne, who was not involved in the study.
DWV can be nasty. Like many other viruses in bees, DWV spreads in two ways. Honey worker bees ( Apis mellifera ) orally transmitted to other workers, usually causing a mild infection. But the parasite varroa is a support, too. When the mite feeds on bee pupae, infecting them with DWV, the virus causes horrific malformations. The young bees develop with swollen abdomens and shriveled or wrinkled wings, causing one of the worst DWV viral diseases in commercial bee hives
DWV first shot in 04 in commercial bumblebees. the insect Bombus terrestris , is often used in greenhouses, especially to pollinate tomatoes. Commercial breeders initially noticed that about 10% of bumble bees died tiny misshapen wings. Then Elke Genersch the Bee Research Institute Hohen Neuendorf, Germany, and his colleagues discovered that the dead bees were infected with DWV. The researchers suspected that the bees were orally infected bumblebees, because farmers use bees to encourage bumble bees to start new nests.
Nobody knew the extent of DWV in wild bumblebees. Matthias Fürst and Mark Brown of Royal Holloway, University of London, Egham and colleagues collected bees and bumblebees than 26 sites across Britain. The virus was present in 11% of bumblebees and replicate in more than a third of them, suggesting active infection, they report in Nature . The virus is probably more common than these data indicate, Brown noted in a telephone news conference. Bees "on their death bed, will not be taken by our sampling plan," he said
The team found genetic evidence that the virus is shared between species :. When bees and bumble bees lived near each other, the two had a similar strain of the virus. Because DWV was more common among bees, 36% were infected, researchers believe it propagates them to bumblebees. The team also found the same pattern with the fungal pathogen Nosema ceranae , but it does not cause problems for bumblebees.
DWV, secondly, spelled trouble. When researchers fed bumblebees food contaminated with the virus, the symptoms of the disease appeared. (See pictures of bumblebees with deformed wings, not of this study.) The worker bees became ill and died on average 6 days earlier than normal, a significant reduction of the typical life span of 21 days. A bumblebee nest contains less than several hundred worker bees, so any DWV generalized infection could devastate the nest capacity to collect enough food.
Jeff Pettis of the US Department of Agriculture Bee Research Laboratory in Beltsville, Maryland, agrees, it is likely that bees infect bumblebees. "This highlights the need to better manage bees in a responsible manner and to find ways to keep all pollinators," he said. Wild bumble bee populations, which help pollinate certain crops seem to decrease in many places, so the need is urgent. There is no way to treat sick bees, so the best strategy is to keep the honey as healthy beehives as possible, including controlling the varroa mite which aggravate infections in bees.
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