Investigation of rodent reservoirs of emerging pathogens in Côte d'Ivoire, West Africa

Background: One of the main health problems in West Africa remains upsurge of emerging pathogens. Ebola virus disease outbreak occurred in 2014 in Liberia, Guinea and Sierra Leone, Monkeypox virus in Nigeria in 2017 and most recently Lassa virus in Nigeria, Togo and Benin in 2018.  These pathogens have animal reservoirs as vectors for transmission. Proper investigation of the pathogens in their rodent vectors could help  reduce and manage their emergence and spread. Methodology: This study was conducted with an approval from the Côte d’Ivoire Bioethics Community. Small mammal trappings were carried out in  9 sites within three zones namely, peri-urban, peri-rural and protected areas. Liver, lung and kidney tissues from trapped small mammals were  sampled in accordance with the recommended conditions of biosafety and bioethics. The organs were transported in liquid nitrogen to the  laboratory. Molecular tests were used to detect pathogens. Orthopoxviruses and Monkeypox virus were detected in the organs by PCR using  consensus primers targeting the virus surface membrane haemagglutinin (HA) genes, while Leptospira species were detected by PCR using primers  targeting the rrs and lfb1 genes. Results: Out of 4930 night-traps, 256 (5.19%) small mammals were trapped including Crocidura, Rattus, Lophuromys, Praomys, Mus and Mastomys.  Leptospira species were detected in 6 genera from 7 study sites and the infected small mammals accounted for 13.3%. Leptospira sp was detected  mainly in the rodent vector genera Rattus (32.3%), Lophuromys (29.0%), and Praomys (16.1%). Three species of Leptospira were detected and  Leptospira interrogans was the most common frequent species (74.2%). Monkeypox virus was not detected from studied small mammals. Conclusion: The initial data from our investigation indicates the presence of Leptospira sp in rodent vectors, Rattus, Lophuromys and Praomys,  which are the potential small mammalian reservoirs of this pathogen in Cote d’Ivoire

Two-Photon absorption cross-section measurement by thermal lens and nonlinear transmission methods in organic materials at 532 nm and 1064 nm laser excitations

Experimental results concerning two-photon absorption (TPA) cross-section measurement using nonlinear transmission (NLT) method and a new pump-probe mode-mismatched thermal lens (TL) scheme, in picosecond regime are reported. Both methods are used in a prospect of comparison. Values of the TPA coefficient and cross-section in three common solvents (Chloroform, Benzene and Nitrobenzene) and new synthesized perylenediimide derivatives (PDI) at 532nm and 1064nm wavelengths are given

Complexes soufrés du Mercure (II) et du Plomb (II) pour l’optique non linéaire

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Study of Two-Photon absorption in Organic Materials by thermal lensing and nonlinear transmission measurements

Experimental investigations of two-photon absorption (TPA) cross-section using nonlinear transmission (NLT) and a new pump-probe mode-mismatched thermal lens (TL) scheme, in the picosecond regime are reported. Both methods are used in a prospect of comparison. Values of the TPA coefficient and cross-section in perylenediimide derivatives (PDI) at 532 nm and 1064 nm wavelengths are given

A sensitivity study on the role of the swamps of southern Sudan in the summer climate of North Africa using a regional climate model

We used the regional climate model RegCM3 to investigate the role of the swamps of southern Sudan in affecting the climate of the surrounding region. Towards this end, we first assessed the performance of a high resolution version of the model over northern Africa. RegCM3 shows a good skill in simulating the climatology of rainfall and temperature patterns as well as the related circulation features during the summer season, outperforming previous coarser resolution applications of the model over this region. Sensitivity experiments reveal that, relative to bare soil conditions, the swamps act to locally modify the surface energy budget primarily through an increase of surface latent heat flux. Existence of the swamps leads to lower ground temperature (up to 2 °C), a larger north–south temperature gradient, and increased local rainfall (up to 40 %). Of particular importance is the impact on rainfall in the surrounding regions. The swamps have almost no impact on the rainfall over the source region of the Nile in Ethiopia or in the Sahel region; however, they favor wetter conditions over central Sudan (up to 15 %) in comparison to the bare desert soil conditions.Abdus Salam International Centre for Theoretical Physics (Earth System Physics)International Atomic Energy AgencySTEP progra

Impact of an Antenatal Counseling on Use of Modern Family Planning Methods in the Postpartum in Rural Guinea

In Guinea, family planning (FP) uptake remains low. The objective of this study was to compare the impact of two types of antenatal counseling on modern FP uptake in the postpartum in rural Guinea. This was a two-group non-equivalent study comparing the impact of a reinforced antenatal counseling (intervention) to the routine antenatal counseling (control). The study included 404 pregnant women at five rural health centres in Forécariah district, Western Guinea. Each woman was followed up until the ninth month postpartum. The study was conducted from October 12, 2013 to December 30, 2014. Findings showed that at the ninth month postpartum, use of modern FP was significantly higher in the intervention group than in the control group (5.7% and 1.1%, respectively; p=0.024). However, 67.6% and 65.7% of women in the intervention group and the control group, respectively, abstained from sexual intercourse at the sixth month postpartum and had the intention to do so until the child walks. At the ninth month postpartum such women represented 70.5% and 59.5%, respectively. Therefore, a longer study period is recommended to assess the effect of antenatal counseling on use of modern FP in the postpartum in Guinea. Keywords: Antenatal counseling; Family planning; Postpartum; Rural; Guine

Study of multiphoton absorption processes in a perylenediimide derivative using thermal lensing technique Study of multiphoton absorption processes in a perylenediimide derivative using thermal lensing technique

Two multiphoton absorption processes were revealed in a perylenediimide derivative, at the wavelength of 1064 nm, by using the thermal lens technique. One of the observed multiphoton processes is two photon absorption (TPA) while the second is a four photons process. The value of the measured TPA coefficientis β=0.12×10-10 cm W-

Target product profiles for protecting against outdoor malaria transmission.

BACKGROUND\ud \ud Long-lasting insecticidal nets (LLINs) and indoor residual sprays (IRS) have decimated malaria transmission by killing indoor-feeding mosquitoes. However, complete elimination of malaria transmission with these proven methods is confounded by vectors that evade pesticide contact by feeding outdoors.\ud \ud METHODS\ud \ud For any assumed level of indoor coverage and personal protective efficacy with insecticidal products, process-explicit malaria transmission models suggest that insecticides that repel mosquitoes will achieve less impact upon transmission than those that kill them outright. Here such models are extended to explore how outdoor use of products containing either contact toxins or spatial repellents might augment or attenuate impact of high indoor coverage of LLINs relying primarily upon contact toxicity.\ud \ud RESULTS\ud \ud LLIN impact could be dramatically enhanced by high coverage with spatial repellents conferring near-complete personal protection, but only if combined indoor use of both measures can be avoided where vectors persist that prefer feeding indoors upon humans. While very high levels of coverage and efficacy will be required for spatial repellents to substantially augment the impact of LLINs or IRS, these ambitious targets may well be at least as practically achievable as the lower requirements for equivalent impact using contact insecticides.\ud \ud CONCLUSIONS\ud \ud Vapour-phase repellents may be more acceptable, practical and effective than contact insecticides for preventing outdoor malaria transmission because they need not be applied to skin or clothing and may protect multiple occupants of spaces outside of treatable structures such as nets or houses

Molecular diagnostics by PCR of poxviruses (Orthopoxvirus (OPV) and Molluscum contagiosum virus (MCV)) in Cote d'Ivoire West Africa

The Orthopoxvirus (OPV) and the Molluscum contagiosum virus (MCV) are Poxviruses involved in viruses skin lesions in humans. OPV infects many vertebrates and MCV mainly infects humans. A diagnostic confusion is often observed between the clinical lesions due to the different Poxviruses firstly and secondly with other viruses like the virus of the chickenpox. In Côte d'Ivoire, the diagnosis of MCV remains essentially clinical and that of OPV is non-existent despite the risk of circulation of the virus. This study aims to implementthe molecular detection of the OPV and the MVC in Côte d'Ivoire. Material and method: Cowpoxvirus DNA and 21 DNA extracts from suspicious cutaneous lesions of the MCV were analyzed by conventional PCR. The consensus primers (EACP1, EACP2) designed from the surface hemagglutin gene were used for the detection of the OPVs and the primers (MCV1, MCV2) targeting the K fragment of the MCV were used for the MCV’s detection . A growing dilution series of the Cowpoxvirus DNA and the MCV allowed the study of the method’s sensitivity used. The DNAs of S.aureus, M. ulcerans, VZV, HSV, the Measles virus and Varicella virus were used for the specificity tests. Results: The detection of the OPV from the Cowpoxvirus viral strain was positive with a positivity threshold at 10-1 dilution. That of the MCV DNA from the suspected MCV's lesion was positive with a positivity threshold of up to 10 -6 dilution. No non-specific amplification was observed with the DNAs of the other pathogens responsible for lesions Cutaneous. The clinical diagnosis of the MCV was confirmed by PCR in 18 out of the 21 patients, ie 85.71%. On the 3 patients with a negative MCV PCR, 2 were positive for the OPV PCR , reflecting the risk of confusion between clinical lesions due to Poxviruses.Keyvords: Molecular diagnostic, Poxviruses, West Afric