A move to scrub poo from dirty chicken crates has spared New Zealanders from hundreds of cases of Campylobacter, authorities say.

New research presented to a health conference has revealed that New Zealand’s once-dire problem with the painful and embarrassing gastro bug is a thing of the past thanks to industry changes.

At its peak, the country’s campylobacter epidemic was the worst in the western world, costing $60 million a year, mostly in lost wages from people forced to take days off work to nurse their sore stomachs and stop the contagious spread.

Infected poultry was a leading source of the condition.

Gail Duncan from the Ministry for Primary Industries told the NZ Population Health Congress in Auckland that simple changes to poultry processing regulations led to a radical 58 per cent drop in infections.

A key change was to start washing the crates used to transport chickens to the processing plants, creating a cleaner environment and halting the cross contamination that was fuelling the epidemic.