A serological survey for leptospiral agglutinins among patients in a Barbadian general practice - abstract

ABSTRACT

Sera from 1,419 patients who attended a Barbadian general practice for a variety of complaints between 1st April and 30th April 1988 were examined for leptospiral agglutinins by the microscopic agglutination test. Sera from patients presenting with pyrexia of unknown origin, jaundice or kidney complaints, and from those whose titre was > 1400, were also examined by the ELISA for IgM and IgG antibodies. Only one patient was diagnosed clinically as possibly having mild leptospirosis, but three others had been recently infected and some mild cases may have been missed. Altogether, 177 of the patients (12.5 percent) were positive at titres> 150. These were 104 of the 739 males (14 percent) and 73 of the 680 females (11 percent) (no statistically significant difference). Seropositivity tended to increase with age (p<0.01), and the highest rates were in agricultural workers (35 percent), labourers (24 percent) and non-manual outdoor workers (19 percent). The difference in seropositivity between the various indoor and outdoor occupational groups was highly significant (p<0.005). Autumnalis (31 percent of the sero postives), Panama (15 percent), Australia (14 percent) and Pyrogenes (11 percent) were the serogroups most commonly recorded among the seropositive patients. Autumnalis predominated in each of the main occupational groups except indoor non-manual workers where Panama, Pyrogenes and Australis occurred more frequently. Ninety-five per cent of the positive titres ranged between 150 and 1400. Titres tended to increase with age, but there was no obvious association between higher titres and particular occupations (AU)