Persistence of leptospiral agglutinins in Trinidadian survey subjects

✍ Scribed by C. O. R. Everard; S. Bennett

• Publisher: Springer
• Year: 1990
• Tongue: English
• Weight: 426 KB
• Volume: 6
• Category: Article
• ISSN: 0393-2990
• DOI: 10.1007/bf00155547

✦ Synopsis

Participants in a survey for leptospiral agglutinating antibodies undertaken in Trinidad, West Indies, in 1977-78, were further monitored for up to 5-and-a-half years. 52 individuals with a titre >_ 1:400 were matched for age, sex and occupation with seronegative subjects. They were re-bled twice (on average 2.38 and 4.84 years later), and changes of titre were noted. At the first follow-up, 78% of negative controls remained negative, and 22%, showed titre changes. Among the seropositive subjects, 47% showed a fall in titre, 38% showed no change, and in 15% the titre rose. New exposure rates between the original and first follow-up samples were 96/1,000 survey population per year in the controls, and 68/1,000 for the subjects with titres >_ 1:400. Between the first and second followup, 47% of the seropositive subjects lost titre, 40% showed no change, and 13% showed a rise in titre. These data demonstrate that although antibody titres may be maintained for a few years at the same level, or show a loss as is usually expected, about 8.3% of individuals in Trinidad may be infected/ reinfected per year.

The infection/reinfection rate is an important factor in the epidemiology of leptospirosis.