Environmental Exposure and Leptospirosis, Peru

Abstract

Human infection by leptospires has highly variable clinical manifestations, which range from subclinical infection to fulminant disease. We conducted a population-based, cross-sectional seroepidemiologic study in Peru to determine potential relationships of environmental context to human exposure to Leptospira and disease associated with seroconversion. Three areas were studied: a flooded, urban slum in the Peruvian Amazon city of Iquitos; rural, peri-Iquitos villages; and a desert shantytown near Lima. Seroprevalence in Belen was 28% (182/650); in rural areas, 17% (52/316); and in a desert shantytown, 0.7% (1/150). Leptospira-infected peridomestic rats were found in all locales. In Belen, 20 (12.4%) of 161 patients seroconverted between dry and wet seasons (an incidence rate of 288/1,000). Seroconversion was associated with history of febrile illness; severe leptospirosis was not seen. Human exposure to Leptospira in the Iquitos region is high, likely related both to the ubiquity of leptospires in the environment and human behavior conducive to transmission from infected zoonotic sources.

Seroprevalence and factors associated with Leptospira infection in an urban district of Cali, Colombia

“…The highest seroprevalence (19%) was reported for people living in SES-1, suggesting an endemic leptospirosis pattern in that zone. The older age group showed the highest Leptospira seroprevalence (18.9%), as described in previous studies, likely due to longer lifetime exposure 9,18,19,20 .…”

“…Walking barefoot indoors or outdoors was not significantly associated with the presence of leptospiral antibodies in the study by Ferro et al 9 , but it has been reported as a risk factor elsewhere 20,40,41 . Interestingly, one study from Rural Durango, Mexico found that Leptospira exposure was positively associated with history of domestic travel in the general population 19 .…”

“…These findings are likely explained by the study sampling and large improvement of the public services in recent years in some areas of District 18, but there are several SES-1 areas without access to public services or with flooding areas. Many studies on leptospirosis patients have widely documented that the disease is particularly prevalent in communities with inadequate sanitation 3,16,20,36,37,38,39 .…”

“…Several SES-1 areas of District 18 present open sewers, temporary accumulation of garbage piles, unpaved streets, and rainwater puddles; all of which are environmental conditions that increase proliferation of rodents and wandering of stray animals, and could ultimately explain a higher risk for Leptospira infection. Although the socioeconomic stratification systems (if available or existing) could vary among countries, leptospirosis-endemic urban areas are characterized by environmental conditions as the aforementioned 3,9,10,16,20,22,36,38,39 . Being uninsured was directly associated with Leptospira infection, but it was marginally associated after multivariate analysis (aOR = 2.94; 95%CI: 1.01-8.59; p = 0.05), therefore confounding is possible.…”

Pesquisa de aglutininas anti-Leptospira em soros de equinos de tração em Porto Alegre, Brasil

“…Dentre estas, os equinos são considerados importantes reservatórios devido sua proximidade com os seres humanos, principalmente quando as duas espécies compartilham um ambiente de condições estruturais e sanitárias inadequadas (Johnson et al, 2004;Hamond et al, 2012).…”