There is currently no indication that the case of foot-and-mouth disease (FMD) identified in Hungary last week was introduced to the farm through animal movements or semen, the European Commission has said.
It said that there is lesser certainty whether it was introduced via equipment or vehicles and the role of people carrying the virus on to the farm remains unclear.
It has now been just over a week since Hungary declared its first case of the highly contagious virus in 50 years.
The virus was found on a dairy farm with almost 1,400 head near the Slovakian border. No further cases of the disease have been identified.
It has since been confirmed that two different yards, about five minutes away from each other, are involved - a dairy farm and a corresponding fattening unit. There were 1,372 cattle culled, 1,064 of which tested positive for the disease.
Wild animals
The Commission has said that while hunting is banned in the 10km restriction zone around the farm, efforts should be made to obtain as many samples as possible from wild cloven-hoofed animals, taking into account hunting rules. Samples obtained from wild boar - shot and found dead - should also be tested for the disease, it said.
Further testing has confirmed that the serotype of the disease is O, the same serotype found in Germany earlier this year.
However, the German authorities have confirmed that the virus found in Germany and the one identified in Hungary are clearly genetically distinct and there is no epidemiological connection between the outbreaks.
Tracing of milk tanks that visited the farm, rendering plant lorries and manure is ongoing. The semen used on the farm has been found to come from approved AI centres.
Movements off farm
On 27 February, a cattle trader moved a bull off the fattening unit to an assembly centre in Vas county, over an hour west of the farm.
On the same day, it was transported to a factory in Austria and was slaughtered on 3 March.
The Commission said that the bull has undergone two official inspections, with no signs of foot-and-mouth detected.
Movement tracing of the cattle trader found three contact holdings in the same county as the outbreak and one in Vas county, which are being investigated.
Based on the available information, the Commission estimates that the date of the first infection on the farm was 27 or 28 February 2025.
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