An exclusion zone in northern Victoria has been lifted after an investigation by Agriculture Victoria declared the threat of bluetongue virus (BTV) to be "very localised and does not show any ongoing cycle of transmission". A media statement from AgVic said the&nbsp;investigation confirmed BTV antibodies&nbsp;were&nbsp;present among a “small number of dairy cows” in the zone&nbsp;and&nbsp;transmission had only been at a local level. "The outcome has demonstrated that the screening protocols for live export have worked and we thank the farmers involved in the testing for cooperating with the local AgVic staff," the statement read. In mid-October&nbsp;there was a 100-km restriction zone placed around a farm in Echuca after it was declared there was evidence of BTV antibodies present in cattle that underwent pre-export testing. RELATED:&nbsp;Bluetonge virus zone around Echuca property in place for 30 days. AgVic&nbsp;enforced strict guidelines once the virus had been identified&nbsp;within the zone which included extensive surveillance measures and an export exclusion for the affected area. Victoria’s chief vet, Dr Charles Milne, said there are no longer “restrictions” on livestock exports from within the zone and international trade can recommence. “We are now able to conduct further&nbsp;surveillance within the area&nbsp;based on the new knowledge gained from the investigation,” Dr Milne said. Dr Milne outlined that the possibility of&nbsp;BTV&nbsp;becoming&nbsp;established within Victoria is&nbsp;low. Australian live heifer exports to China&nbsp;are worth approximately $100 million per year and&nbsp;the restriction had the potential to sever an important source of income for Australian farmers. The&nbsp;virus is non-contagious&nbsp;and is only transferred&nbsp;from animal-to-animal&nbsp;by “midges”, a common flying insect that is considered to be&nbsp;the main transmitter. BTV&nbsp;does not&nbsp;pose any quality or food safety health risks to dairy products or meat from affected livestock.