The evolutionary history of hepaciviruses.

In the search for natural reservoirs of hepatitis C virus (HCV), a broad diversity of non-human viruses within the Hepacivirus genus has been uncovered. However, the evolutionary dynamics that shaped the diversity and timescale of hepaciviruses evolution remain elusive. To gain further insights into the origins and evolution of this genus, we screened a large dataset of wild mammal samples (n = 1,672) from Africa and Asia, and generated 34 full-length hepacivirus genomes. Phylogenetic analysis of these data together with publicly available genomes emphasizes the importance of rodents as hepacivirus hosts and we identify 13 rodent species and 3 rodent genera (in Cricetidae and Muridae families) as novel hosts of hepaciviruses. Through co-phylogenetic analyses, we demonstrate that hepacivirus diversity has been affected by cross-species transmission events against the backdrop of detectable signal of virus-host co-divergence in the deep evolutionary history. Using a Bayesian phylogenetic multidimensional scaling approach, we explore the extent to which host relatedness and geographic distances have structured present-day hepacivirus diversity. Our results provide evidence for a substantial structuring of mammalian hepacivirus diversity by host as well as geography, with a somewhat more irregular diffusion process in geographic space. Finally, using a mechanistic model that accounts for substitution saturation, we provide the first formal estimates of the timescale of hepacivirus evolution and estimate the origin of the genus to be about 22 million years ago. Our results offer a comprehensive overview of the micro- and macroevolutionary processes that have shaped hepacivirus diversity and enhance our understanding of the long-term evolution of the Hepacivirus genus.

Detection of first gammaherpesvirus sequences in Central African bats.

Herpesviruses have been identified in many species; however, relatively few bat herpesvirus are known, considering the enormous diversity of bats. We used consensus PCR to test bats from the Republic of the Congo and found DNA of two different novel bat herpesviruses. One was detected in a Pipistrellus nanulus, the other in a Triaenops persicus bat and both resemble gammaherpesviruses. On the amino acid level, the amplified sequences differ by 55% from each other, and by 27% and 25% from the next closest known viruses. The findings point towards the diversity of herpesviruses in Central African bats.

Nodding syndrome since 2012: recent progress, challenges and recommendations for future research.

We aim to review the current epidemiology of nodding syndrome (NS) and discuss relevant gaps in research. NS and convulsive epilepsy of unknown aetiology are clustered within the same villages and families in onchocerciasis-endemic areas. They are therefore potentially different clinical expressions of the same disease. It has been difficult to perform full autopsies on NS patients who die in remote villages. Adequate fixation of tissue immediately after death is critical for the examination of brain tissue. Therefore, post-mortem transsphenoidal brain biopsies, performed immediately after death by trained nurses, will provide the best option for obtaining tissue for analysis. We suspect that certain blackflies in onchocerciasis-endemic areas may transmit a novel pathogen that could cause NS and epilepsy. This is supported by a recent drop in the number of new NS cases coinciding with vector control activities aimed at reducing blackfly populations in northern Uganda. We propose that metagenomic studies of human samples, blackflies and microfilariae are conducted to screen for pathogens, and that a clinical trial is planned to evaluate the impact of larviciding against NS and epilepsy epidemics.

Mapping the distribution of the main host for plague in a complex landscape in Kazakhstan: An object-based approach using SPOT-5 XS, Landsat 7 ETM+, SRTM and multiple Random Forests.

Plague is a zoonotic infectious disease present in great gerbil populations in Kazakhstan. Infectious disease dynamics are influenced by the spatial distribution of the carriers (hosts) of the disease. The great gerbil, the main host in our study area, lives in burrows, which can be recognized on high resolution satellite imagery. In this study, using earth observation data at various spatial scales, we map the spatial distribution of burrows in a semi-desert landscape. The study area consists of various landscape types. To evaluate whether identification of burrows by classification is possible in these landscape types, the study area was subdivided into eight landscape units, on the basis of Landsat 7 ETM+ derived Tasselled Cap Greenness and Brightness, and SRTM derived standard deviation in elevation. In the field, 904 burrows were mapped. Using two segmented 2.5 m resolution SPOT-5 XS satellite scenes, reference object sets were created. Random Forests were built for both SPOT scenes and used to classify the images. Additionally, a stratified classification was carried out, by building separate Random Forests per landscape unit. Burrows were successfully classified in all landscape units. In the 'steppe on floodplain' areas, classification worked best: producer's and user's accuracy in those areas reached 88% and 100%, respectively. In the 'floodplain' areas with a more heterogeneous vegetation cover, classification worked least well; there, accuracies were 86 and 58% respectively. Stratified classification improved the results in all landscape units where comparison was possible (four), increasing kappa coefficients by 13, 10, 9 and 1%, respectively. In this study, an innovative stratification method using high- and medium resolution imagery was applied in order to map host distribution on a large spatial scale. The burrow maps we developed will help to detect changes in the distribution of great gerbil populations and, moreover, serve as a unique empirical data set which can be used as input for epidemiological plague models. This is an important step in understanding the dynamics of plague.

[Description of Nosopsyllus (N.) atsbi n. sp. (Siphonaptera: Ceratophyllidae) from Ethiopia, and revision of the related species N. (N.) incisus (Jordan & Rothschild, 1913); biogeographical discussion]. / Description de Nosopsyllus (N.) atsbi n. sp. (Siphonaptera : Ceratophyllidae) d'Ethiopie et révision de l'espèce affine N. (N.) incisus (Jordan & Rothschild, 1913) ; discussion biogéographique.

We describe a new Nosopsyllus s. sto., N. atsbi, from the north of Ethiopia, that shows phyletic similarities with N. incisus (Jordan & Rothschild, 1913), a species from the oriental part of the afrotropical region. This led us to reconsider the classification of the incisus populations based on the unique criteria of telomere's setation (three robust marginal bristles, instead of the two typically present in members of this genus and subgenus). It appears that N. incisus s. sto. occurs in north-eastern Democratic Republic of the Congo, Kenya, Burundi and Tanzania. In the north and south of this region (respectively central Ethiopia, on one hand, Zambia and Malawi, on the other hand), two taxa are morphologically distinct and we erect them here to the rank of subspecies: Nosopsyllus (N.) incisus traubi n. ssp. and N. (N.) incisus lewisi n. ssp. Actually, four taxa are in "incisus complex", namely: N. atsbi n. sp., N. incisus traubi n. ssp., N. incisus incisus (Jordan & Rothschild, 1913), and N. incisus lewisi n. ssp.

[Siphonaptera from Tanzania. Description of two taxa and complementary description of Ctenophthalmus cophurus Hemingwayi Hubbard, 1963 (Siphonaptera: Ctenophthalmidae)]. / Siphonaptères de Tanzanie. Description de deux taxa et compléments a la description de Ctenophthalmus cophurus Hemingwayi Hubbard, 1963 (Siphonaptera : Ctenophthalmidae).

Two new taxa, Ctenophthalmus (Ethioctenophthalmus) iraqwi n. sp. and C. (E.) evidens derocki n. ssp. are described and a complementary description is given for C. (E.) cophurus hemingwayi Hubbard, 1963, all those taxa belonging to the Tanzanian flea fauna.

[Ctenopllhaimus (Ethioctrvophthalmus) kemmelberg n. sp. (Insecta: Siphonaptera: Ctenophthalmidae), a new flea from Tanzania and description of unknown small structures in the mecopteroids]. / Ctenophthamus (Ethioctenophthalmus) kemmelberg n. sp. (Insecta: Siphonaptera: Ctenophthalmidae), puce nouvelle de Tanzanie et description de structures internes non signalées chez les Mécoptèroïdes.

We recently described two new taxa of Siphonaptera (Ctenophthalmus (Ethioctenophthalmus) teucqoe teucqaoe et C. (E.) teucqae shumeensis Laudisoit & Beaucournu, 2007) from Lushoto plague focus (West Usambara mountains, Tanzania). A new taxa is here being studied, Ctenophthalmus kemmelberg, an original flea, not only for its genitalia, but also for original structures appearing, and that have not been described yet, at our knowledge, in any Mecopteroid. These are visible in females only. We suggest the name "Teucq's organs" for those remarkable structures.

[Two new Ctenophthalmus (Insecta: Siphonaptera: Ctenophthalmidae) from Tanzania]. / Deux nouveaux Ctenophthalmus (Insecta : Siphonaptera : Ctenophthalmidae) de Tanzanie.

During a recent epidemiological study of Lushoto plague focus, some uncommon specimens of fleas or even totally new species were collected. In this paper, we describe one of those, Ctenophthalmus (Ethioctenophthalmus) teucqae n. sp. Microscopic observation of comparison specimens deposited at National History Museum (London) allows us to create a sub-species, C. (E.) teucqae shumeensis n. ssp.