Bluetongue was detected in five Bazadaise suckler cattle in Lancashire, England.
The cattle were imported legally from an area in France that is currently battling bluetongue strains one and eight, said NSA chief executive Peter Morris.
The cattle had been vaccinated against the two bluetongue strains 60 days before travelling to the UK.
However, the cattle appeared to have been infected with BTv1 around the same time as they were vaccinated, and showed low level viremia when post-imported tested by DEFRA.
Morris said DEFRA suggested there was a relatively low risk of onward transmission to UK midges and other stock, as the affected cattle had been culled on detection of the disease.
Following the detection of the disease, the NFU called for a suspension of imports from bluetongue-susceptible areas.
NFU president Peter Kendall said it is important to keep the disease out of the UK due to a lack of BTv1 vaccine.