SEROEPIDEMIOLOGY OF CANINE LEPTOSPIROSIS ON THE ISLAND OF BARBADOS

Previous surveillance in Barbados documented the absence of infection with Leptospira serogroup Canicola in dogs. The aim of this study was to survey the current state of canine leptospirosis in Barbados, 10 ye ars after the last survey. Sera from 78 unwanted dogs scheduled for eu thanasia and 61 dogs suspected of having acute leptospirosis were test ed by microscopic agglutination (MAT) and by an ELISA method adapted f or canine IgM and IgG antibodies. The seroprevalence in unwanted dogs was 62% (48/78), at an MAT titre of greater than or equal to 100. The majority of animals had low titres, suggestive of previous infection. Serogroup Autumnalis was the most common reactor (45%), followed by se rogroups Icterohaemorrhagiae and Australis (each 16%) and Pomona (13%) . Serogroup Ballum was uncommon in this group. The seroprevalence dete rmined by MAT in acutely-ill dogs was 75% (46/61). The most common pre dominant serogroup was Icterohaemorrhagiae (36%) followed by serogroup Australia (13%), while serogroups Autumnalis and Ballum were also of little significance. Paired specimens were available from eight acutel y-ill dogs. One animal was seronegative while five dogs showed evidenc e of seroconversion. An IgM-ELISA titre of greater than or equal to 32 0 was used to confirm current infection in eight of these nine animals . Previous studies in Barbados showed a higher prevalence of serogroup Icterohaemorrhagiae than of Autumnalis, but the relative frequency of these two serogroups may be changing. The high seroprevalence in dogs is of public health concern because the close contact between dogs an d man may provide the link between a reservoir in the environment and susceptible humans. (C) 1997 Elsevier Science B.V.