Molecular, antigenic, and pathogenic characterization of H5N8 highly pathogenic avian influenza viruses isolated in the Democratic Republic of Congo in 2017

In May 2017, high mortality of chickens and Muscovy ducks due to the H5N8 highly pathogenic avian influenza virus (HPAIV) was reported in the Democratic Republic of Congo (DR Congo). In this study, we assessed the molecular, antigenic, and pathogenic features in poultry of the H5N8 HPAIV from the 2017 Congolese outbreaks. Phylogenetic analysis of the eight viral gene segments revealed that all 12 DR Congo isolates clustered in clade 2.3.4.4B together with other H5N8 HPAIVs isolated in Africa and Eurasia, suggesting a possible common origin of these viruses. Antigenically, a slight difference was observed between the Congolese isolates and a representative virus from group C in the same clade. After intranasal inoculation with a representative DR Congo virus, high pathogenicity was observed in chickens and Muscovy ducks but not in Pekin ducks. Viral replication was higher in chickens than in Muscovy duck and Pekin duck organs; however, neurotropism was pronounced in Muscovy ducks. Our data confirmed the high pathogenicity of the DR Congo virus in chickens and Muscovy ducks, as observed in the field. National awareness and strengthening surveillance in the region are needed to better control HPAIVs

Evaluation of the efficacy of flumethrin for tsetse control in Lutendele, Democratic Republic of Congo

In the Democratic Republic of Congo animal and human Afri­can trypanosomoses are rife over very large areas. Pigs are the major feeding hosts of Glossina fuscipes quanzensis, the sole tsetse fly species present in suburban Kinshasa. In the context of integrated disease control, pig breeding could be used to advantage in tsetse control by applying insecticides on these animals. The aim of this study was to test this hypothesis by comparing the efficacy of flumethrin 1% as a pour-on formu­lation on pigs with the use of flumethrin-treated screens to control G. f. quanzensis and animal trypanosomosis in Luten­dele, suburban Kinshasa. After two years of applications, ento­mological surveys showed that the pour-on treatment of pigs reduced more the apparent density of tsetse flies than the flu­methrin-treated screens although the difference was not signif­icant. Throughout the study no parasite could be detected in the pigs by the parasitological method nor by molecular biol­ogy, but overall 28% of the pigs had positive serology (95% confidence interval [CI]: 21-33). Compared to treated screens, the treatment of pigs with flumethrin was identified as a signif­icant protective factor against seropositivity with an odds ratio equal to 0.28 (95% CI: 0.12-0.57). This study reveals that both control methods significantly reduced tsetse apparent densi­ties, but that the pour-on treatment of pigs seems to be more efficacious than the use of treated screens to protect them against trypanosomosis

Highly Pathogenic Avian Influenza A(H5N8) Virus, Democratic Republic of the Congo, 2017

In 2017, highly pathogenic avian influenza A(H5N8) virus was detected in poultry in the Democratic Republic of the Congo. Whole-genome phylogeny showed the virus clustered with H5N8 clade 2.3.4.4B strains from birds in central and southern Asia. Emergence of this virus in central Africa represents a threat for animal health and food security

Long-term expression of melanopsin and channelrhodopsin causes no gross alterations in the dystrophic dog retina

International audienceSeveral preclinical studies have investigated the potential of algal channelrhodopsin and human melanopsin as optogenetic tools for vision restoration. In the present study, we assessed the potentially deleterious effects of long-term expression of these optogenes on the diseased retina in a large animal model of retinal degeneration, the RPE65-deficient Briard dog model of Leber congenital amaurosis. Intravitreal injection of adeno-associated virus vectors expressing channelrhodopsin and melanopsin had no effect on retinal thickness over a 16-month period post injection. Our data support the safety of the optogenetic approach for the treatment of blindness

Long-term expression of melanopsin and channelrhodopsin causes no gross alterations in the dystrophic dog retina

International audienceSeveral preclinical studies have investigated the potential of algal channelrhodopsin and human melanopsin as optogenetic tools for vision restoration. In the present study, we assessed the potentially deleterious effects of long-term expression of these optogenes on the diseased retina in a large animal model of retinal degeneration, the RPE65-deficient Briard dog model of Leber congenital amaurosis. Intravitreal injection of adeno-associated virus vectors expressing channelrhodopsin and melanopsin had no effect on retinal thickness over a 16-month period post injection. Our data support the safety of the optogenetic approach for the treatment of blindness