Human leptospirosis in the Seychelles (Indian Ocean): a population-based study.

Abstract

Abstract. A leptospirosis surveillance program was carried out for 12 months on the entire population of the Seychelles. Diagnosis was assessed by both microagglutination test and polymerase chain reaction (PCR) assay. In this population of 74,331, leptospirosis was clinically suspected in 125 subjects and confirmed in 75 patients (incidence of 101 per 100,000; 95% confidence interval ϭ 79-126). Leptospirosis was more frequent in middle-aged males with environmental exposure. Eight serogroups were identified and Icterohaemorrhagiae (31%) and Hurstbridge (20%) were the most frequent. Hurstbridge, a recently identified new serogroup, was implicated in severe cases and death. Influenza-like forms accounted for 37% of the cases while jaundice, acute renal failure, and pulmonary hemorrhage occurred in 52%, 28%, and 19%, respectively. Death occurred in six patients and was related to pulmonary hemorrhage. The PCR result was positive after completion of treatment in eight patients, suggesting that the administered five-day course of penicillin may be inadequate to eradicate the bacteria.

Pulmonary haemorrhage as a predominant cause of death in leptospirosis in Seychelles

“…The study was a population-based surveillance conducted between 1 April 1995 and 31 March 1996. The detailed study design was reported previously (YERSIN et al, 1998). In brief, all doctors of the country were asked to refer during this period any patient who had fever or any of the following signs or symptoms: myalgia, tender liver, jaundice, ARF, bleeding tendency, radiological lung infiltrates, and meningism which could not be accounted for by a definite diagnosis other than leptospirosis.…”

“…19951. ' Leptospirosis is endemic in Seychelles: Previous reports indicated a high annual incidence ranging from 45 to 101 per 100 000, and frequent hepatic, renal, and haemorrhagic complications (PINN, 1992;YERSIN et al, 1998).…”

Pathology and pathophysiology of pulmonary manifestations in leptospirosis

“…Pulmonary hemorrhage occurred in 14 of 75 patients (19%) in the Seychelles, causing the deaths of six patients [27]. In a 1987 epidemic in Korea, 37 of 93 patients (40%) with leptospirosis had hemoptysis, massive in all 5 patients who died [28].…”

First isolation of Leptospira fainei serovar Hurstbridge from two human patients with Weil's syndrome

“…This was related to the fact that none of 62 control sera (from laboratory staff) gave similar titres and no cross-reactions to other leptospiral serovars could be demonstrated [1]. A leptospirosis surveillance programme in the Seychelles identi®ed L. fainei by a PCR assay and by an MAT as the second most frequent serotype infecting human patients with suspected leptospiral infection, and a correlation to severe cases of human infection was con®rmed [2].…”

“…Overall, the serogroups Icterohaemorrhagiae, Sejroe and Saxkoebing have most clinical relevance. Recently, L. fainei has been suspected as a new human pathogen [1,2]. L. fainei serovar Hurstbridge was ®rst isolated from culled sows in Australia in 1994 [3], and it is both a new species and a previously unknown serogroup (Hurstbridge).…”