A VIRAL disease which paralyses bees has been sweeping through populations of honeybees across the globe.

Severe outbreaks of Chronic Bee Paralysis (CBP) can lead to the destruction of whole colonies – and the disease is now reported to be spreading exponentially in Britain.

CBP occurs in two distinct forms; in one type, the affected bees have trembling wings and bodies, and lose the ability to fly. Mounds of dead bees may be found on the ground near the entrance to the hive. In the second form of the disease, the bees lose all the hairs on the abdomen, which assumes a greasy, black appearance.

Samples submitted to the National Bee Unit database showed that in 2007, the disease was present in only Lincolnshire, but a decade later has been discovered in 39 of 47 English counties and six of eight Welsh counties. However, with no statutory requirement for beekeepers to register as animal keepers, it can be difficult to keep track of the disease spreading.

A team of scientists led by Prof Giles Budge of Newcastle University examined data from 130,000 honeybee imports from 25 countries, finding that for the first time that the disease was twice as likely in apiaries owned by beekeepers who imported honeybees.

It has also been suggested that commercial beekeeping could be contributing to the spread of the disease because they tend to manage large colonies, and the virus appears to be rapidly transmitted in densely populated hives.

However, Prof Budge explained that bee farmers in the UK tend to be quite ‘small-scale’: “A standard bee farmer might have 100 to 200 colonies. In the States, they have up to 10,000. Even in Germany there will be huge-scale beekeeping going on.”

Although the viral disease has been around for centuries, researchers are keen to discover if a new, more virulent strain is behind its global surge. In the United States, CBPV prevalence was 0.7% in 2010 but reached 16% in 2014. Prevalence doubled in Italy from 5% to 10% between 2009 and 2010. In China, prevalence has grown from 9% to 38%.

Infected adult bees carry the virus for up to six days without showing symptoms and may spread it to other colonies at sites where different bees forage for food. A quarter of beekeepers have multiple sites, so could be assisting the spread of the disease.

Veterinary pathologist Chris Palgrave recommended that hive density within an area must be kept low enough to prevent food shortages and therefore the chances of hungry bees raiding another colony for their honey stores.

“Beekeepers are encouraged to place each hive facing different directions and with other distinguishing features such as different coloured entrances,” Mr Palgrave suggested.

He added that there might also be difficulty controlling diseases like CBP as bee keeping registration is on a voluntary only basis.

“It would make control efforts futile, if in the area where there is an outbreak you have unregistered colonies that are spreading the disease,” he warned.

Chairman of the Bee Farmers’ Association, Rob Nickless, concluded: “Researchers will continue to examine the genetics of the disease to determine if there is a new strain and seek to discover whether imported queens are bringing the disease into Britain, or whether those queens are simply more susceptible to the virus that is already here.”