Detection of Pathogenic Leptospires in Water and Soil in Areas Endemic to Leptospirosis in Nicaragua

In Nicaragua, there are ideal environmental conditions for leptospirosis. The objective of this investigation was to detect pathogenic and saprophytic leptospires in water and soil samples from leptospirosis-endemic areas in Nicaragua. Seventy-eight water and 42 soil samples were collected from houses and rivers close to confirmed human cases.Leptospiraspp was isolated in Ellinghausen-McCullough-Johnson-Harris (EMJH) culture medium with 5-fluororacil and positive samples were analyzed through PCR for theLipL32gene, specific for pathogenic leptospires (P1 clade). There were 73 positive cultures from 120 samples, however only six of these (5% of all collected samples) were confirmed to be pathogenic, based on the presence of theLipL32gene (P1 clade). Of these six pathogenic isolates, four were from Leon and two from Chinandega. Four pathogenic isolates were obtained from water and two from soil. This study proved the contamination of water and soil with pathogenic leptospires, which represents a potential risk for public health

"The Great Event of the Fortnight”: Steamship Rhythms and Colonial Communication

This paper engages with Tim Cresswell’s ‘contellations of mobility’ in order to contribute some understanding of historical maritime rhythms. The empirical focus is upon a steamship mail service in the post-emancipation Caribbean. In examining this communications network, it is stressed that while those managing the network valorised predictable efficiency, ‘friction’ was prized by mercantile groups at the steamers’ ports of call. Thus, the different aspects of mobility signified differently across the network, and this historical case study reinforces the resonance of slowness and stoppage time. The synchronisation of steamship arrivals with sociocultural norms in the Caribbean colonies also necessitated the adaptation of mail service rhythms. Through a focus on shipping operations, this paper proposes to temper our understanding of the role of steamship technology in empire. The influence of colonies on the metropole encompassed an alteration of the rhythms of imperial circulation, and it is within the maritime arena that these realities came into sharp focus

Evolutionary ecology of Chagas disease; what do we know and what do we need?

International audienceThe aetiological agent of Chagas disease, Trypanosoma cruzi, is a key human pathogen afflicting most populations of Latin America. This vectorborne parasite is transmitted by haematophageous triatomines, whose control by large-scale insecticide spraying has been the main strategy to limit the impact of the disease for over 25 years. While those international initiatives have been successful in highly endemic areas, this systematic approach is now challenged by the emergence of insecticide resistance and by its low efficacy in controlling species that are only partially adapted to human habitat. In this contribution, we review evidences that Chagas disease control shall now be entering a second stage that will rely on a better understanding of triatomines adaptive potential, which requires promoting microevolutionary studies and –omic approaches. Concomitantly, we show that our knowledge of the determinants of the evolution of T. cruzi high diversity and low virulence remains too limiting to design evolution-proof strategies, while such attributes may be part of the future of Chagas disease control after the 2020 WHO's target of regional elimination of intradomiciliary transmission has been reached. We should then aim at developing a theory of T. cruzi virulence evolution that we anticipate to provide an interesting enrichment of the general theory according to the specificities of transmission of this very generalist stercorarian trypanosome. We stress that many ecological data required to better understand selective pressures acting on vector and parasite populations are already available as they have been meticulously accumulated in the last century of field research. Although more specific information will surely be needed, an effective research strategy would be to integrate data into the conceptual and theoretical framework of evolutionary ecology and life-history evolution that provide the quantitative backgrounds necessary to understand and possibly anticipate adaptive responses to public health interventions

Marginality and the Third Space of Unadopted Plotlander Roads

This article explores the characteristics and relationships of marginality in informal space and plotlander housing in the context of Homi K. Bhabha’s cultural hybridity and Third Space. To illustrate and examine the processes of marginalization that defined informal space in the United Kingdom, this article will critically analyze the previously undocumented plotlander community at Studd Hill on the North Kent coastline.1 Examining key aspects of this sites social origins and its marginal spatial context reveals the positive implications and challenges of informal space and social hybridization. In this analysis, issues of spatial vulnerability and marginality of plotlander communities are critically reframed as analogous to the sociospatial characteristics and innovative practices highlighted by Bhabha in postcolonial hybrid space. Focusing specifically on the challenges of the unadopted roads at Studd Hill, this article’s comparisons reveal how the anarchistic emergence of plotlander housing in the United Kingdom has produced innovative solutions to their social marginality that reflect the spatial values of postcolonial hybrid spaces