Resistance to African swine fever virus among African domestic pigs appears to be associated with a distinct polymorphic signature in the RelA gene and upregulation of RelA transcription

Abstract African swine fever virus (ASFV) is a highly contagious and fatal hemorrhagic disease of domestic pigs, which poses a major threat to the swine industry worldwide. Studies have shown that indigenous African pigs tolerate ASFV infection better than European pigs. The porcine v-rel avian reticuloendotheliosis viral oncogene homolog A (RelA) encoding a p65 kD protein, a major subunit of the NF-kB transcription factor, plays important roles in controlling both innate and adaptive immunity during infection with ASFV. In the present study, RelA genes from ASFV-surviving and symptomatic pigs were sequenced and found to contain polymorphisms revealing two discrete RelA amino acid sequences. One was found in the surviving pigs, and the other in symptomatic pigs. In total, 16 nonsynonymous SNPs (nsSNPs) resulting in codon changes were identified using bioinformatics software (SIFT and Polyphen v2) and web-based tools (MutPre and PredictSNP). Seven nsSNPs (P374-S, T448-S, P462-R, V464-P, Q478-H, L495-E, and P499-Q) were predicted to alter RelA protein function and stability, while 5 of these (P374-S, T448-S, P462-R, L495-E, and Q499-P) were predicted as disease-related SNPs. Additionally, the inflammatory cytokine levels of IFN-α, IL-10, and TNF-α at both the protein and the mRNA transcript levels were measured using ELISA and Real-Time PCR, respectively. The resulting data was used in correlation analysis to assess the association between cytokine levels and the RelA gene expression. Higher levels of IFN-α and detectable levels of IL-10 protein and RelA mRNA were observed in surviving pigs compared to healthy (non-infected). A positive correlation of IFN-α cytokine levels with RelA mRNA expression was also obtained. In conclusion, 7 polymorphic events in the coding region of the RelA gene may contribute to the tolerance of ASFV in pigs

Le système de production de la poule locale contraint son développement au Sud-Kivu, Est de la République Démocratique du Congo

Objectif : Cette étude a été menée envue de caractériser le système de production et de reproduction de la poule locale dans trois zones agro-écologiques du Sud-Kivu d’Avril jusqu’en Décembre, 2017. Méthodologie et résultats: Une enquête transversale a été menée à l’aide d’une interview auprès de 360 éleveurs répartis dans 3 zones agro-écologiques dont la haute, moyenne et basse altitude. Les principaux résultats trouvés indiquent que ces élevages sont gérés par les hommes, ayant un objectif tourné vers le marché (90,28%), comptent 24,38 poules qui sont élevés en divagation (94,17%) sans logement spécifique (81,11%). Les poules reçoivent une supplémentation alimentaire (65,28%) et un complément vitaminique (25,83%). La pseudopeste aviaire est la maladie la plus fréquente (89,72%), suite à l’absence de la vaccination (96,67%), les éleveurs recourent à la pharmacopée traditionnelle (77,5%). Chaque poule donne 13 œufs par cycle de ponte pour 2,96 cycles par an. 70,37% des œufs pondus sont incubés pour un taux d’éclosion de 84,50% et un taux de sevrage de 57,25%, intervenant à 2,52 mois après éclosion. Les épidémies et la prédation sont les principales contraintes auxquelles font face les éleveurs de la poule locale en plus du manque d’appuis par les services étatiques. Conclusion et application des résultats: Quoique cet élevage soit une activité secondaire et selon les techniques de production traditionnelle avec des faibles performances, il reste primordiale dans l’économie des familles rurales et mérite une attention particulière visant son amélioration. Une stabulation ainsi qu’une alimentation équilibrée permettraient d’accroitre la production et réduire les risques de perte des poules.Mots clés : Elevage, zones-agro écologiques, Contraintes, poule locale, Sud-Kivu

Natural occurrence of Beauveria bassiana (Ascomycota: Hypocreales) infecting Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) and earwig in eastern DR Congo

Abstract Background The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), poses a threat to the food security of populations in sub-Saharan Africa because of its damage to maize crops. As alternative to the use of hazardous pesticides, microbial control is one of the most promising sustainable approaches adopted to limit the damages caused by S. frugiperda. The sampling targeted mainly larvae of S. frugiperda; however, during the survey, cadavers of earwig found on the same sampling sites were also collected and involved in the study. Cadavers of targeted insects, with and without sign of fungal infection, were sampled from 3 localities in eastern DR Congo. Culture of fungal isolates was performed in selective Sabouraud dextrose agar media. Results Morphological study of fungal features such as conidia (shape and size) and conidiophores showed that the isolates were from the genus Beauveria. Conidial measurements were highly variable and ranged from 2.4 to 3.6 µm in length and from 1.75 to 3.0 µm in width. Molecular characterization and phylogenetic analysis of the 2 Beauveria isolates based on DNA sequencing of ITS-5.8S region confirmed that both isolates belong to Beauveria bassiana. The 2 isolates of B. bassiana P5E (OP419735.1) and KA14 (OP419734.1) were isolated from cadavers of FAW and earwig, respectively. The alignment with different sequences of B. bassiana from different continent showed that P5E belonged to the same clade of previous isolates reported from Iran and Mexico, while KA14 was with the same clade as isolates from Kenya and China. Conclusion To our knowledge, this is the first study reporting the occurrence of B. bassiana infecting FAW and earwig in eastern DR Congo and in Africa

Bioclimatic zonation and potential distribution of Spodoptera frugiperda (Lepidoptera: Noctuidae) in South Kivu Province, DR Congo

Abstract Background The fall Armyworm (FAW) Spodoptera frugiperda (JE Smith), is currently a devastating pest throughout the world due to its dispersal capacity and voracious feeding behaviour on several crops. A MaxEnt species distributions model (SDM) was developed based on collected FAW occurrence and environmental data’s. Bioclimatic zones were identified and the potential distribution of FAW in South Kivu, eastern DR Congo, was predicted. Results Mean annual temperature (bio1), annual rainfall (bio12), temperature seasonality (bio4) and longest dry season duration (llds) mainly affected the FAW potential distribution. The average area under the curve value of the model was 0.827 demonstrating the model efficient accuracy. According to Jackknife test of variable importance, the annual rainfall was found to correspond to the highest gain when used in isolation. FAWs’ suitable areas where this pest is likely to be present in South Kivu province are divided into two corridors. The Eastern corridor covering the Eastern areas of Kalehe, Kabare, Walungu, Uvira and Fizi territories and the Western corridor covering the Western areas of Kalehe, Kabare, Walungu and Mwenga. Conclusions This research provides important information on the distribution of FAW and bioclimatic zones in South Kivu. Given the rapid spread of the insect and the climatic variability observed in the region that favor its development and dispersal, it would be planned in the future to develop a monitoring system and effective management strategies to limit it spread and crop damage

Etiology of early-onset neonatal sepsis and antibiotic resistance in Bukavu, Democratic Republic of the Congo

Background: The Democratic Republic of the Congo (DRC) has one of the highest neonatal death rates (between 14% and 28%) in the world. In the DRC, neonatal sepsis causes 15.6% of this mortality, but data on the bacterial etiology and associated drug susceptibility are lacking. Methods: Hemocultures of 150 neonates with possible early-onset neonatal sepsis (pEOS) were obtained at the Hôpital Provincial Général de Référence de Bukavu (Bukavu, DRC). The newborns with pEOS received an empirical first-line antimicrobial treatment (ampicillin, cefotaxime, and gentamicin) based on the synopsis of international guidelines for the management of EOS that are in line with World Health Organization (WHO) recommendations. Isolates were identified using matrix-assisted laser desorption/ ionization time-of-flight mass spectrophotometry. Antibiotic resistance was assessed using the disk diffusion method. Results: Fifty strains were obtained from 48 patients and identified. The 3 most prevalent species were Enterobacter cloacae complex (42%), Klebsiella pneumoniae (18%), and Serratia marcescens (12%). Enterobacter cloacae isolates were resistant to all first-line antibiotics. All K. pneumoniae and S. marcescens isolates were resistant to ampicillin, and the majority of the K. pneumoniae and half of the S. marcescens isolates were resistant to both cefotaxime and gentamicin. All E. cloacae complex strains, 89% of K. pneumoniae, and half of S. marcescens had an extended-spectrum ß-lactamase phenotype. Conclusions: The most prevalent pathogens causing EOS in Bukavu were E. cloacae complex, K. pneumoniae, and S. marcescens. Most of these isolates were resistant to the WHO-recommended antibiotics