A Rift Valley fever risk surveillance system for Africa using remotely sensed data: potential for use on other continents.

The authors developed a monitoring and risk mapping system using normalized difference vegetation index (NDVI) times series data derived from the advanced very high resolution radiometer (AVHRR) instrument on polar orbiting national oceanographic and atmospheric administration (NOAA) satellites to map areas with a potential for a Rift Valley fever (RVF) outbreaks in sub-Saharan Africa. This system is potentially an important tool for local, national and international organisations involved in the prevention and control of animal and human disease, permitting focused and timely implementation of disease control strategies several months before an outbreak. We are currently developing a geographic information system (GIS)-based remotely sensed early warning system for potential RVF vectors in the United States.

A GIS tool to estimate West Nile virus risk based on a degree-day model.

West Nile virus (Flaviviridae: Flavivirus) is a serious infectious disease that recently spread across the North America continent. A spatial analysis tool was developed on the ArcMap 9.x platform to estimate potential West Nile virus activity using a spatially explicit degree-day model.

Mosquito larval habitat mapping using remote sensing and GIS: implications of coalbed methane development and West Nile virus.

Potential larval habitats of the mosquito Culex tarsalis (Coquillett), implicated as a primary vector of West Nile virus in Wyoming, were identified using integrated remote sensing and geographic information system (GIS) analyses. The study area is in the Powder River Basin of north central Wyoming, an area that has been undergoing a significant increase in coalbed methane gas extractions since the late 1990s. Large volumes of water are discharged, impounded, and released during the extraction of methane gas, creating aquatic habitats that have the potential to support immature mosquito development.

Risk factors associated with herd-level exposure of cattle in Nebraska, North Dakota, and South Dakota to bluetongue virus.

Objective: To evaluate herd-level risk factors for seropositive status of cattle to 1 or more bluetongue viruses.

Animals: 110 herds of cattle in Nebraska, North Dakota, and South Dakota.

Procedure: Blood samples were collected before and after the vector season.

Culture-independent analysis of midgut microbiota in the arbovirus vector Culicoides sonorensis (Diptera: Ceratopogonidae).

Differences in midgut microbial communities inhabiting Culicoides spp., insect vectors of virus pathogens, may affect the variation observed in the ability of these biting midges to propagate arthropod-borne viruses. As a first step toward addressing this hypothesis, midgut bacterial communities were compared between Culicoides species expected to be efficient and inefficient vectors of virus pathogens.