Immune Response After Leptospirosis Infection (SERO7LEPTO)

Serological Response in Patients Infected by Leptospirosis 1 to 7 Years Earlier

Leptospirosis is a zoonotic infection induced by pathogen bacteria (genus: Leptospira) growing in water polluted by animal fluids. Due to its 10 fold occurence in French overseas aera, and especially in Reunion Island, as compared to metropoly, it is considered as a major public health issue.

An important inter-individual variability in humoral immune response suggests that vaccination should be recommended in exposed subjects.

This cohort study aimed to determine if subjects that have been infected by leptospirosis for 1 to 7 years still remain immunized, and then do not need vaccination.

Study Overview

• Status: Unknown
• Conditions: Leptospirosis
• Intervention / Treatment: Other: cohort

Detailed Description

Every year more than 500 000 severe forms of leptospirosis are diagnosed in Reunion Island. The risk of mucocutaneous contact with contaminated media remains important due to highly aqueous environment.

Cured subjects that have been infected for 1, 2, 3, 4, 5, 6 or 7 years will be enrolled. The qualitative and quantitative humoral immune response to leptospirosis infection will also be evaluated to determine whether they still get protective immunization. Leptospirosis immunization will be evaluated using micro-agglutination test.

Graded immune responses related to the severity and the length of the infection will also be investigated.

Finally, 3 methods used for leptospirosis diagnosis will be compared. It is expected from this study to evaluate the appropriate conditions in which new vaccination could be required to prevent further leptospirosis infection in cured subjects.

• Study Type: Observational
• Enrollment (Anticipated): 175

Contacts and Locations

• Study Contact: Name: CHRISTINE JUHEL, PHD; Phone Number: +262262359949; Email: christine.juhel@chu-reunion.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Leptospirosis-cured subjects that have undergone leptospirosis

Description

Inclusion Criteria:

• Subjects diagnosed for leptospirosis by polymerase chain reaction measured in Reunion Island Hospital between 209-2015
• with social security issue

Exclusion Criteria:

• Leptospirosis diagnosis not confirmed by polymerase chain reaction
• subject exhibiting immunodepressive status (cancers, transplantation, immune deficit, blood disorders)
• under medication: corticoids, immunosuppressor, chemiotherapy

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Leptospirosis immunization assessed by serum immunoglobulin	Humoral immune response will be measured in serum cured-subjects using micro-agglutination test	1-7 years after leptospirosis infection

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
rate of still-immunized patients	Seropositive subjects will be measured using the ELISA serion method and the ELISA recombinant protein method	1-7 years after leptospirosis infection
comparison of 3 diagnosis method for leptospirosis	Matched results of the 3 methods: micro-agglutination test, ELISA serion method and ELISA recombinant protein method will be compared	1-7 years after leptospirosis infection

Collaborators and Investigators

• Sponsor: Centre Hospitalier Universitaire de la Réunion
• Collaborators: Institut Pasteur
• Investigators: Principal Investigator: NICOLAS TRAVERSIER, MD, CHU de la Réunion

Study record dates

Study Major Dates

• Study Start: October 1, 2016
• Primary Completion (Anticipated): December 1, 2017
• Study Completion (Anticipated): September 1, 2018

Study Registration Dates

• First Submitted: September 8, 2016
• First Submitted That Met QC Criteria: September 8, 2016
• First Posted (Estimate): September 13, 2016

Study Record Updates

• Last Update Posted (Estimate): September 13, 2016
• Last Update Submitted That Met QC Criteria: September 8, 2016
• Last Verified: September 1, 2016

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Infections; Gram-Negative Bacterial Infections; Bacterial Infections; Bacterial Infections and Mycoses; Spirochaetales Infections; Leptospirosis; Weil Disease
• Other Study ID Numbers: 2015/CHU/07

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO