Seroepidemiology of leptospirosis in dogs from rural and slum communities of Los Rios Region, Chile.

Background: Leptospirosis is a zoonotic disease of global importance and often neglected as a public health problem due to lack of awareness, under-diagnosis and under-reporting. Animals serve as a source of transmission through the shedding of Leptospira in their urine. Because of their proximity to humans, dogs may play a role in human infections.

Agricultural landscape and spatial distribution of Toxoplasma gondii in rural environment: an agent-based model.

Background: Predicting the spatial distribution of pathogens with an environmental stage is challenging because of the difficulty to detect them in environmental samples. Among these pathogens, the parasite Toxoplasma gondii is the causative agent of the zoonosis toxoplasmosis, which is responsible for public health issues. Oocysts of T.

When should a trophically and vertically transmitted parasite manipulate its intermediate host? The case of Toxoplasma gondii.

Parasites with complex life cycles are expected to manipulate the behaviour of their intermediate hosts (IHs), which increase their predation rate and facilitate the transmission to definitive hosts (DHs). This ability, however, is a double-edged sword when the parasite can also be transmitted vertically in the IH. In this situation, as the manipulation of the IH behaviour increases the IH death rate, it conflicts with vertical transmission, which requires healthy and reproducing IHs.

Quantitative estimation of the viability of Toxoplasma gondii oocysts in soil.

Toxoplasma gondii oocysts spread in the environment are an important source of toxoplasmosis for humans and animal species. Although the life expectancy of oocysts has been studied through the infectivity of inoculated soil samples, the survival dynamics of oocysts in the environment are poorly documented. The aim of this study was to quantify oocyst viability in soil over time under two rain conditions.

Development of a sensitive method for Toxoplasma gondii oocyst extraction in soil.

Toxoplasmosis is a world-wide infection caused by Toxoplasma gondii. Oocysts disseminated in the environment by infected cats provide a major source of infection for humans and intermediate hosts. The level of soil contamination and the dynamics of this contamination are mostly unknown due to the lack of sensitivity of detection method.

Persistence of Bacillus thuringiensis israelensis (Bti) in the environment induces resistance to multiple Bti toxins in mosquitoes.

Background: The simultaneous production of six different toxins by Bacillus thuringiensis israelensis (Bti) is thought to delay the evolution of resistance in treated mosquito populations. Recent studies have shown that Bti can persist and proliferate in the environment, thereby imposing continuous selective pressure on mosquito populations, raising concerns about the long-term effectiveness of this bioinsecticide. In order to evaluate the effect of Bti persistence on the evolution of resistance, the authors selected a laboratory Aedes aegypti L.