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Oswaldo Cruz Foundation, Brazilian Ministry of Health, Brazil


Urban slum health, emerging infectious diseases

LMIC Affiliation

Oswaldo Cruz Foundation (Fiocruz), Brazilian Ministry of Health

Site Description

The Oswaldo Cruz Foundation (Fiocruz), the research branch of the Brazilian Ministry of Health, and Yale University have a long-standing research and training program in the city of Salvador, which focuses on health problems that have emerged due rapid urbanization and the growth of urban slum settlements. The program focuses on infectious diseases such as leptospirosis (a rat-borne disease which is the cause of epidemics of pulmonary hemorrhage syndrome), bacterial meningitis, acute respiratory infections (e.g. COVID-19), vaccine preventable diseases and arboviruses. The site also provides research training opportunities in non-communicable diseases which affect slum populations such as hypertension, food insecurity and violence. Furthermore, Fiocruz and Yale coordinate a Global Infectious Disease Training Program and sponsored ten Fulbright fellows and ten Global Health Equity Scholars and Fogarty International Clinical Research Scholars in the past 20 years.

Ongoing projects include a National Institute of Allergy and Infectious Diseases (NIAID)-supported project about naturally acquired and vaccine-mediated immunity to leptospirosis. This cohort study of 14,000 urban slum residents was initiated in 2003 and focuses on characterizing the natural history of leptospirosis and determining the effectiveness of improved sanitation and other community-based interventions in preventing this zoonotic disease. The objectives include determining prospectively whether naturally-acquired infection induces robust anti-Leptospira protein responses and whether these responses are correlates of immunity to reinfection and identifying the specific Leptospira proteins which elicit attenuated vaccine and naturally-acquired immunity and whether immunization with these antigens confers cross-protective immunity.

Additional ongoing studies include a Yale-supported project exploring COVID-19 transmission in urban communities. This cohort study of 2,500 urban slum residents was initiated in 2019 and seeks to characterize the introduction of COVID-19 into Brazil. The aim is determining prospectively the attack rate, risk factors for transmission and evaluate the effectiveness of preventive interventions as vaccines.

A NIH/NIAD-funded project is studying the natural history of Zika virus congenital infection. The goal of this project is to prospectively evaluate the role of an early immunologic response in protecting against congenital transmission of Zika virus and developing clinical disease in offspring.

The Wellcome Trust supports a project to deliver improved sanitation interventions to prevent urban leptospirosis transmission. This quasi-experimental cluster trial evaluates the efficacy of sanitation strategies with and without community engagement to reduce the incidence of Leptospira infection in Salvador, Brazil over five years. Additionally, this project will elucidate the mechanism by which closing sewer interventions reduce direct human contact with sewage and environmental pathogen load in urban slums.

With funding from the Bill and Melinda Gates Foundation to do advanced pathogen detection in an urban ‘hot spot, metagenomic next generation sequencing is being incorporated into clinical settings that serve a large urban region to detect and identify pathogens that are otherwise easy to miss, which would offer the opportunity to respond to outbreaks in Salvador before they become a global threat.

Site Mentors

Albert Ko, MD, Department Chair and Professor of Epidemiology (Microbial Diseases) and of Medicine (Infectious Diseases), Yale School of Public Health

Federico Costa, PhD, Associate Professor Adjunct of Epidemiology (Microbial Diseases), Yale School of Public Health

Mitermayer G. Reis, MD, PhD, Professor Adjunct of Epidemiology (Microbial Diseases), Yale School of Public Health; Professor, Federal University of Bahia, Bahian School of Medicine and Public Health; Head of the Laboratory of Pathology and Molecular Biology, Oswaldo Cruz Foundation