Hardworking honeybees which ensure the hive is kept hygienically clean is a way of saving the hive from disaster due to infestations of parasitic mites and the viruses that can kill colonies.

The varroa mite sucks the blood of pupae of worker bees, reducing their immunity to disease and transmitting viruses. The mites also find their way into the honeycombs, then lay their eggs and feed on the larvae in the safety of the wax-capped cells. When the cells are uncapped to release the adult bees the mites are also released – ready to parasitise other members of the hive.

Bees that have been trapped with mites are often smaller, and can show signs of infection with a disease called deformed wing virus. If present together, varroa mites and this virus can kill off a whole hive.

Clean worker bees sniff out dead or diseased larvae, uncap their cells and dispose of the contents. Although any adult mites inside may survive this upheaval, their young offspring are killed. Intensive cleaning behaviour is highly effective at controlling mite numbers and protects the hive against deformed wing virus.

Francis Ratnieks of the University of Sussex in Brighton and colleagues studied this behaviour in 42 honeybee colonies. In each hive they placed a section of honeycomb that had been frozen to kill the pupae inside. Within a day, most colonies had uncapped and removed up to half of the dead pupae, but some particularly hygienic colonies managed to remove more than 95 per cent.

Ratnieks' team found that these super-hygienic colonies had less than half the varroa mite levels of the less hygienic colonies. Also, while around a third of less hygienic colonies had individuals with shrivelled wings – a sign of deformed wing virus – the 14 colonies that threw out at least 80 per cent of the pupae had none, suggesting that hygienic behaviour can protect hives against viruses too.

"This finding could be very useful for beekeepers as it would reduce the harmful effects of varroa in a natural way," says Ratnieks.

What's more, studies have shown that the tidying behaviour is a heritable trait, suggesting that it has a genetic component. "You can breed for this behaviour by screening colonies for hygiene levels and the breeding the most hygienic," says Ratnieks.

His team has confirmed this in a separate study, which found that when queens from hygienic colonies mate with drones from another hygienic colony, cleaning levels in new colonies populated by the offspring remain high.

But to avoid reinfection, all beekeepers must be using hygienic colonies, warns Marla Spivak of the University of Minnesota in St Paul. "When some beekeepers have susceptible stock with colonies full of mites, healthy colonies with low levels of mites try to rob honey out of these weakened colonies and get re-infested," she says.