Poor farm biosecurity helped in the spread of pig wasting disease PMWS, a new study has claimed.
The British Pig Executive-funded research, carried out by the University of Warwick, found that it took just three years for the disease to become endemic in the UK pig herd after it was first identified in south-east England in 2000.
It spread slowly north and, by 2003, the first cases were identified in Scotland.
Factors associated with farms that broke down early in the epidemic were more than 600 sows and bringing in gilts.
During the foot-and-mouth epidemic of 2001, when most animal movements stopped, farms that broke down were more likely to be located near a grower unit and allowed visitors on to their farm who had not been pig-free for three days.
After foot-and-mouth, herd size and proximity to other pig farms were associated with the introduction of PMWS on to units.
Laura Green, who headed the study, said: "The results from this first analysis indicate that introduction of PMWS may have occurred via pig movements, visitors and local spread.
"As with all infectious disease, good biosecurity may help delay or prevent introduction to a farm."
She urged all livestock farmers to be careful in purchasing and quarantining new stock on farm to reduce the risks of bringing diseases on to units.
She also said better visitor control was required and that pig farmers needed to ensure that anyone coming on to their unit had been free of pigs for at least three days.
Controlling birds, rodents and other wildlife could also assist in preventing disease.
She added: "These practices apply to all diseases. PMWS is a timely reminder of this."