Inter-epidemic Rift Valley fever virus seropositivity in an irrigation scheme in Bura, southeast Kenya

Rift Valley Fever (RVF) is an acute mosquito-borne viral zoonosis that causes cyclical epidemics in sub-Saharan Africa, with recent incursions into the Arabian Peninsula. Outbreaks of RVF are associated with above average rainfall and flooding, in which large numbers of vectors emerge. Recent studies into the interepidemic maintenance of RVF virus (RVFV) suggest that both vertical transmission in vectors and direct transmission between hosts, in combination with predisposing ecosystems, are responsible for persistence of the virus. A longitudinal survey was carried out in Tana River County, Kenya, in three ecosystems (irrigated, riverine and pastoral) from September 2014 – June 2015. The objectives of the study were to investigate possibility of low-level RVFV transmission during an inter-epidemic period, to examine variation in RVFV seroprevalence in sheep and goats across these ecosystems and to determine the risk factors for RVFV transmission. 316 small ruminants were selected and tested for immunoglobulin G antibodies against RVFV nucleoprotein using a competitive ELISA during 6 visits. Data on potential risk factors was also captured. The overall RVF virus seropositivity was 12.3% (95%CI = 9%-16.6%) by the end of the study. This varied across the sampling sites with the pastoral ecosystem having a significantly higher seroprevalence at 26.1% (95%CI = 16.6%-38.3%, p0.05) in the irrigated area (7) and in the riverine area (11). Seroconversions were significantly associated with presence of water either due to rainfall or irrigation (p<0.05). This study indicates that RVFV is circulating in the studied area. It also highlights the risk posed by land use changes, such as the creation and expansion of irrigation schemes, in increasing the risk of inter-epidemic RVFV transmission. This is through provision of necessary environmental conditions for vegetative growth thus providing vectors with more breeding grounds, shade and resting places, which further prolong their lifespans thereby propagating the virus. The findings provide policy makers with the evidence needed for vector and RVF prevention and control within this changing environment

Identification of Tsetse (Glossina spp.) using matrix-assisted laser desorption/ionisation time of flight mass spectrometry

Glossina (G.) spp. (Diptera: Glossinidae), known as tsetse flies, are vectors of African trypanosomes that cause sleeping sickness in humans and nagana in domestic livestock. Knowledge on tsetse distribution and accurate species identification help identify potential vector intervention sites. Morphological species identification of tsetse is challenging and sometimes not accurate. The matrix-assisted laser desorption/ionisation time of flight mass spectrometry (MALDI TOF MS) technique, already standardised for microbial identification, could become a standard method for tsetse fly diagnostics. Therefore, a unique spectra reference database was created for five lab-reared species of riverine-, savannah- and forest- type tsetse flies and incorporated with the commercial Biotyper 3.0 database. The standard formic acid/acetonitrile extraction of male and female whole insects and their body parts (head, thorax, abdomen, wings and legs) was used to obtain the flies' proteins. The computed composite correlation index and cluster analysis revealed the suitability of any tsetse body part for a rapid taxonomical identification. Phyloproteomic analysis revealed that the peak patterns of G. brevipalpis differed greatly from the other tsetse. This outcome was comparable to previous theories that they might be considered as a sister group to other tsetse spp. Freshly extracted samples were found to be matched at the species level. However, sex differentiation proved to be less reliable. Similarly processed samples of the common house fly Musca domestica (Diptera: Muscidae; strain: Lei) did not yield any match with the tsetse reference database. The inclusion of additional strains of morphologically defined wild caught flies of known origin and the availability of large-scale mass spectrometry data could facilitate rapid tsetse species identification in the futur

Development of an integrated approach to proactively classify and manage slow-moving inventory

Dem Bestandsmanagement wird in Unternehmen eine stetig steigende Bedeutung beigemessen. Die Möglichkeit, durch ein effizientes Bestandsmanagement Kosten zu reduzieren, ist für viele Unternehmen im Hinblick auf einen langfristigen Unternehmenserfolg wichtig. Im Fokus des Bestandsmanagements stehen oft schnelldrehende Materialien, die sich durch geringe Reichweiten und hohe Lagerumschläge auszeichnen. Das Potenzial eines systematischen Managements von langsamdrehenden Materialien wurde bisher noch nicht untersucht. Dieses Paper greift diese Thematik auf und liefert einen Beitrag zum Bestandsmanagement für langsamdrehende Materialien.Inventory management becomes a more important role within companies. Cost minimization through efficient inventory management is an important aspect with regards to a long-term profitability. Inventory management often focuses on fast moving materials, which are defined through low reach of stock values or high inventory turnrates. A possible systematic management of slow moving materials has not been analyzed yet. This paper therefore investigates this potential and makes a contribution to inventory management for slow moving materials

Host preference of tsetse: An important tool to appraise the Nagana risk of cattle in the cotton zone of Mali

Nagana, a vector-borne epizootic caused by trypanosomes, severely constrains the use of draught animals in the cotton zone of south-eastern Mali. The disease causes considerable economic losses for the local farmers due to high mortality and morbidity ensuing productivity losses. Nagana is routinely controlled by the use of trypanocides and an overreliance on their use throughout past decades resulted in multiple drug resistance of trypanosomes in most parts of West Africa's cotton belt. Designing alternative, effective vector control strategies requires an identification of the preferred hosts of tsetse flies through blood meal analysis as a prerequisite for estimating infection risk. A survey was, therefore, conducted between November 2008 and April 2009, catching 474 Glossina species which were dissected. Blood meals were smeared on filter paper (Whatman®-FTA-Cards) for laboratory analysis. DNA extractions and amplification using universal vertebrate cytochrome b primers of 120 assorted samples detected 74 DNA-containing specimens. The subsequent use of cattle-specific primers yielded 52 visible amplicons in the gel electrophoresis. Sequencing and BLASTN® analysis of the remaining samples revealed 19 blood meals matching with existing sequences of the human genome in Genbank®. Two samples originated from crocodiles whereas one was unidentifiable