Using an enzyme-linked immunosorbent assay (ELISA) and Western blottin
g techniques, cats from the north west of England and North Wales were
tested for antibodies to Borrelia burgdorferi. Seropositivity to B bu
rgdorferi in these cats was similar (4.8 per cent) to that found in do
gs and horses in the UK from non-endemic areas. Cross-reactive antibod
ies to Leptospira interrogans serovars did not affect the cat B burgdo
rferi ELISA data. Clinical signs of Lyme disease were generally absent
; lameness was rarely reported. As in other species, it must be consid
ered that high levels of serum anti-borrelia antibodies are not diagno
stic for clinical Lyme disease.