The varroa mite is causing a highly contagious virus to proliferate in honeybee colonies here and around the globe, Hawaii and British researchers have found.

Researchers from the University of Hawaii, the University of Sheffield in South Yorkshire, the British Marine Biological Association, and the British Food and Environmental Research Agency studied the pest in Hawaii.

Their research, reported Friday in the journal Science, showed how the varroa mite caused the virus, a known pathogen, to increase its frequency among honeybee colonies to 100 percent from 10 percent.

The study showed that along with this change, a millionfold increase in the number of virus particles infect- ing each bee and a huge reduction in viral strain diversity led to the single virulent virus that deforms wings.

The varroa mite lives on the surface of honeybees, feeds off their blood and reproduces on their developing brood.

The deformed wing virus is transmitted between bees during mating or feeding. Mites introduce the virus into the bee’s blood while feeding on the blood, thus creating a new transmission route that bypasses many of the bees’ natural defenses.

The strain remains even after the mites are removed.

The association of the deformed wing virus and the varroa mite is believed to contribute to the worldwide spread of the virus and the probable end of millions of honeybee colonies.

The varroa is a large mite (1.5 mm by 1 mm), discovered on Oahu in 2007, while another pest, the small hive beetle, was found in 2010. Both have devastated wild colonies and managed hives on Oahu and Hawaii island.

Bees are essential not only to honey production but to crop production because they help pollinate plants.