From microbiomes to road kill: What DNA can tell us about the ecology of ticks

Knowledge of host species that maintain populations of Ixodes scapularis, the vector of Lyme disease in the eastern U.S., is needed to improve preventative strategies. The prevailing dogma of Lyme disease ecology is that the white-footed mouse (Peromyscus leucopus) is the most important host for juvenile ticks (i.e., larvae and nymphs; 1). The white-tailed deer (Odocoileus virginanus) is the primary host for adult ticks, however its role as a host for juveniles has not been rigorously studied. Here we provide both DNA and visual evidence that juveniles feed on O. virginanus. Our DNA-based host detection system may be more broadly applied in future studies to identify other important hosts of I. scapularis

Use of migdut dissections and PCR blockers in the study of the eukaryotic microbiome of the black-legged tick

Bioinformatics is a field that can improve understanding of biological systems. In this study, DNA isolated from the black-legged tick (Ixodes scapularis) was analysed using QIIME2 microbiome bioinformatics software on the Cyverse platform. Use used PCR blockers and dissections were tested to reduce the amount of I. scapularis reads and thus allow for increased sequencing fungal and protist DNA reads

Ecological correlates of risk and incidence of West Nile virus in the United States

West Nile virus, which was recently introduced to North America, is a mosquito-borne pathogen that infects a wide range of vertebrate hosts, including humans. Several species of birds appear to be the primary reservoir hosts, whereas other bird species, as well as other vertebrate species, can be infected but are less competent reservoirs. One hypothesis regarding the transmission dynamics of West Nile virus suggests that high bird diversity reduces West Nile virus transmission because mosquito blood-meals are distributed across a wide range of bird species, many of which have low reservoir competence. One mechanism by which this hypothesis can operate is that high-diversity bird communities might have lower community-competence, defined as the sum of the product of each species’ abundance and its reservoir competence index value. Additional hypotheses posit that West Nile virus transmission will be reduced when either: (1) abundance of mosquito vectors is low; or (2) human population density is low. We assessed these hypotheses at two spatial scales: a regional scale near Saint Louis, MO, and a national scale (continental USA). We found that prevalence of West Nile virus infection in mosquito vectors and in humans increased with decreasing bird diversity and with increasing reservoir competence of the bird community. Our results suggest that conservation of avian diversity might help ameliorate the current West Nile virus epidemic in the USA

The Spatial Heterogeneity between Japanese Encephalitis Incidence Distribution and Environmental Variables in Nepal

To identify potential environmental drivers of Japanese Encephalitis virus (JE) transmission in Nepal, we conducted an ecological study to determine the spatial association between 2005 Nepal JE incidence, and climate, agricultural, and land-cover variables at district level.District-level data on JE cases were examined using Local Indicators of Spatial Association (LISA) analysis to identify spatial clusters from 2004 to 2008 and 2005 data was used to fit a spatial lag regression model with climate, agriculture and land-cover variables.Prior to 2006, there was a single large cluster of JE cases located in the Far-West and Mid-West terai regions of Nepal. After 2005, the distribution of JE cases in Nepal shifted with clusters found in the central hill areas. JE incidence during the 2005 epidemic had a stronger association with May mean monthly temperature and April mean monthly total precipitation compared to mean annual temperature and precipitation. A parsimonious spatial lag regression model revealed, 1) a significant negative relationship between JE incidence and April precipitation, 2) a significant positive relationship between JE incidence and percentage of irrigated land 3) a non-significant negative relationship between JE incidence and percentage of grassland cover, and 4) a unimodal non-significant relationship between JE Incidence and pig-to-human ratio.JE cases clustered in the terai prior to 2006 where it seemed to shift to the Kathmandu region in subsequent years. The spatial pattern of JE cases during the 2005 epidemic in Nepal was significantly associated with low precipitation and the percentage of irrigated land. Despite the availability of an effective vaccine, it is still important to understand environmental drivers of JEV transmission since the enzootic cycle of JEV transmission is not likely to be totally interrupted. Understanding the spatial dynamics of JE risk factors may be useful in providing important information to the Nepal immunization program

Recurrent Mutations of the Exportin 1 Gene (XPO1) in Primary Mediastinal B-Cell Lymphoma: A Lysa Study

International audience57th Annual Meeting of the American-Society-of-Hematology, Orlando, 201

Recurrent Mutations of the Exportin 1 Gene (XPO1) in Primary Mediastinal B-Cell Lymphoma: A Lysa Study

International audience57th Annual Meeting of the American-Society-of-Hematology, Orlando, 201