The observation of the first two outbreaks of bovine parafilariosis in Belgium led to a preliminary epidemiological investigation conducted through a telephone survey among veterinarians in a limited area around the outbreaks. Typical clinical signs consisting of bleeding spots and areas of oedema were recorded, and the aetiology was confirmed through the observation of typical embryonated eggs of Parafilaria bovicola in the exudate. The localisation of the lesions on the withers, neck, back and, to a smaller extent, the rump of the animals, and their first appearance in early spring, were additional useful epidemiological observations. The clinical herd prevalence in the area was 14.1 per cent (95 per cent confidence interval 11.3 to 17.2 per cent), suggesting that bovine parafilariosis is established in the area.