The document discusses the global leptospirosis epidemic, presenting the disease as a complex zoonosis with significant annual cases and deaths. It emphasizes the need for a coherent strategy for detection, confirmation, and control of outbreaks, including potential roles for vaccination and environmental decontamination. The Global Leptospirosis Environmental Action Network (GLEAN) aims to enhance prevention and response efforts through a One Health approach, collaborative practices, and improved surveillance.

1. Global
Leptospirosis
Environmental
Action
Network
Strengthen the prevention and
outbreak control strategy
Eric Bertherat, MD, MPH, MSc
Pandemic and Epidemic Diseases
WHO Geneva
Health and Climate
Foundation

2. Leptospirosis: a multifaceted disease
Zoonosis + Environmental disease + Occupational disease
•
•
•
Complex natural history
Complex pathogen agent
Non specific clinical
presentation + severe forms
•
•
Worldwide distribution.
Endemic + seasonal
variations / epidemic
Ko A, Goarant C, Picardeau M. Nature Reviews Microbiology, 2009, 7: 736-747
1,000,000 cases / 60,000 deaths annually
in some areas as high as 975 cases per 100 000

3. Leptospirosis Outbreaks
1970-2008 (n=239)
Outbreak size: mean=465; median=51; range=2-14285.
Source: C. Munoz Zanzi

4. Philippines, 2009
680 cases of leptospirosis /yr with seasonal peak during the rainy season
Typhoon
Pepeng:
3 October
Typhoon Ondoy:
26 September
Thousands of people displaced and
housed in emergency evacuation
centers
In the 2 following weeks, 505 suspect
! cases and 15 deaths in Manila alone

5. Looking for a clear and coherent strategy
Detection and confirmation
–
–
–
What is a leptospirosis case ?
What is an outbreak ?
How to confirm the cases ?
Control
–
Case management:
•
•
•
–
A role for human immunization ?
•
•
•
–
Vaccine serovar specific.
Limited availability.
Does not prevent carriage and release
Mass chemoprophylaxis ?
•
•
•
–
–
Early diagnosis and treatment.
Severe cases
Logistic issues
Efficacy, Logistic issues
High risk groups ?
Up to 6 months of flood waters
Decontamination of the environment ?
Rodent control ?
!Better prediction and preparedness are essential but many key questions still pending

6. The Global Leptospirosis Environmental Action Network (GLEAN)
A One Health Approach
To reduce the impact that leptospirosis outbreaks have on communities
through providing cost-effective, implementable and sustainable solutions
Reducing the impact
of leptospirosis
outbreaks through
cost-effective,
implementable and
sustainable
solutions
Early warning
systems and
Improved
prevention and
control strategies
Increasing the
knowledge of the
relationship between
environmental,
biological, ecological,
economic,
demographic factors
GLEAN: An international Community of Practice
Medical Clinicians, Public health specialists, Veterinarians, Climatologists,
Statisticians, Rodent specialists, Biologists, Anthropologists, Ecologists, Water and
Sanitation Specialists, Economists...

7. How to reduce the impact of the outbreaks ?
 Retrospective analysis of leptospirosis outbreaks
Predict
 Determine baseline
disease incidence
 What are the main
drivers? What are their
predictive potential ?
What type of
prediction to inform
public health
decisions ?
 Develop tool /
validate on site
Prevent
Detect
Relative importance
of potential
preventive
measures ?
Improve lab
confirmation
(protocols, bank of
reference sera,
evaluation of rapid
tests, reference lab
network, training..)
 Role of animals
/human vaccination?
Develop outbreak
detection algorithms
(case definition,
epidemic threshold ?)
Intervene
 Guidance for
outbreak control and
investigation
 Outbreak
preparedness and
capacity building

8. Thank you
3rd GLEAN annual meeting, Brasilia, March 2013