First Report of Sylvatic DENV-2-Associated Dengue Hemorrhagic Fever in West Africa

Dengue virus (DENV) circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF) with thrombocytopenia (13000/µl), a raised hematocrit (32% above baseline) and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain

Disruption of the CCL1-CCR8 axis inhibits vascular Treg recruitment and function and promotes atherosclerosis in mice

The CC chemokine 1 (CCL1, also called I-309 or TCA3) is a potent chemoattractant for leukocytes that plays an important role in inflammatory processes and diseases through binding to its receptor CCR8. Here, we investigated the role of the CCL1-CCR8 axis in atherosclerosis. We found increased expression of CCL1 in the aortas of atherosclerosis-prone fat-fed apolipoprotein E (Apoe)-null mice; moreover, in vitro flow chamber assays and in vivo intravital microscopy demonstrated an essential role for CCL1 in leukocyte recruitment. Mice doubly deficient for CCL1 and Apoe exhibited enhanced atherosclerosis in aorta, which was associated with reduced plasma levels of the anti-inflammatory interleukin 10, an increased splenocyte Th1/Th2 ratio, and a reduced regulatory T cell (Treg) content in aorta and spleen. Reduced Treg recruitment and aggravated atherosclerosis were also detected in the aortas of fat-fed low-density lipoprotein receptor-null mice treated with CCR8 blocking antibodies. These findings demonstrate that disruption of the CCL1-CCR8 axis promotes atherosclerosis by inhibiting interleukin 10 production and Treg recruitment and function.This study was supported by the Spanish Ministerio de Ciencia, Innovación y Universidades (MCIU, grants SAF2016-79490-R and SAF2014-57845-R) and the Instituto de Salud Carlos III (ISCIII, grants PI14/00526, PI17/01395, CP11/00145, and CPII16/00022) with co-funding from the European Regional Development Fund (ERDF, “Una manera de hacer Europa”), the Fundación Ramón Areces, European Union (EuroCellNet COST Action CA15214) and the INSERM. VZG is supported by the ISCIII, JMG-G by the ISCIII Miguel Servet Program and the Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), AdMM by the MCIU (predoctoral contract BES-2014-06779), and ZM by a British Heart Foundation Professorship. The CNIC is supported by the MCIU and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (SEV-2015-0505).S

Evaluation of two molecular methods for the detection of Yellow fever virus genome

Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Columbia University. Mailman School of Public Health. Center for Infection and Immunity. New York, NY, USA.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Pará State University. Department of Pathology. Belém, PA, Brazil.Columbia University. Mailman School of Public Health. Center for Infection and Immunity. New York, NY, USA.Columbia University. Mailman School of Public Health. Center for Infection and Immunity. New York, NY, USA.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Pará State University. Department of Pathology. Belém, PA, Brazil.Yellow fever virus (YFV), a member of the family Flaviviridae, genus Flavivirus is endemic to tropical areas of Africa and South America and is among the arboviruses that pose a threat to public health. Recent outbreaks in Brazil, Bolivia, and Paraguay and the observation that vectors capable of transmitting YFV are presenting in urban areas underscore the urgency of improving surveillance and diagnostic methods. Two novel methods (RT-hemi-nested-PCR and SYBR(«) Green qRT-PCR) for efficient detection of YFV strains circulating in South America have been developed. The methods were validated using samples obtained from golden hamsters infected experimentally with wild-type YFV strains as well as human serum and tissue samples with acute disease

The association of obesity and cardiometabolic traits with incident hfpef and hfref

Objectives:  This study evaluated the associations of obesity and cardiometabolic traits with incident heart failure with preserved versus reduced ejection fraction (HFpEF vs. HFrEF). Given known sex differences in HF subtype, we examined men and women separately. Background:  Recent studies suggest that obesity confers greater risk of HFpEF versus HFrEF. Contributions of associated metabolic traits to HFpEF are less clear. Methods:  We studied 22,681 participants from 4 community-based cohorts followed for incident HFpEF versus HFrEF (ejection fraction ≥50% vs. <50%). We evaluated the association of body mass index (BMI) and cardiometabolic traits with incident HF subtype using Cox models. Results:  The mean age was 60 ± 13 years, and 53% were women. Over a median follow-up of 12 years, 628 developed incident HFpEF and 835 HFrEF. Greater BMI portended higher risk of HFpEF compared with HFrEF (hazard ratio [HR]: 1.34 per 1-SD increase in BMI; 95% confidence interval [CI]: 1.24 to 1.45 vs. HR: 1.18; 95% CI: 1.10 to 1.27). Similarly, insulin resistance (homeostatic model assessment of insulin resistance) was associated with HFpEF (HR: 1.20 per 1-SD; 95% CI: 1.05 to 1.37), but not HFrEF (HR: 0.99; 95% CI: 0.88 to 1.11; p < 0.05 for difference HFpEF vs. HFrEF). We found that the differential association of BMI with HFpEF versus HFrEF was more pronounced among women (p for difference HFpEF vs. HFrEF = 0.01) when compared with men (p = 0.34). Conclusions: Obesity and related cardiometabolic traits including insulin resistance are more strongly associated with risk of future HFpEF versus HFrEF. The differential risk of HFpEF with obesity seems particularly pronounced among women and may underlie sex differences in HF subtypes

Genomic and phylogenetic characterization of Merino Walk virus, a novel arenavirus isolated in South Africa

Merino Walk virus (MWV), a proposed novel tentative species of the family Arenaviridae, was isolated from a rodent, Myotomys unisulcatus, collected at Merino Walk, Eastern Cape, South Africa, in 1985. Full-length genomic sequence confirmed MWV as an arenavirus related distantly to Mobala, Mopeia and Ippy viruses, all members of the Old World arenavirus complex. We propose MWV as a tentative novel species in the Lassa–lymphocytic choriomeningitis virus complex, based on its isolation from a novel rodent species and its genetic and serological characteristics

Negevirus: a Proposed New Taxon of Insect-Specific Viruses with Wide Geographic Distribution

Six novel insect-specific viruses, isolated from mosquitoes and phlebotomine sand flies collected in Brazil, Peru, the United States, Ivory Coast, Israel, and Indonesia, are described. Their genomes consist of single-stranded, positive-sense RNAs with poly(A) tails. By electron microscopy, the virions appear as spherical particles with diameters of ∼45 to 55 nm. Based on their genome organization and phylogenetic relationship, the six viruses, designated Negev, Ngewotan, Piura, Loreto, Dezidougou, and Santana, appear to form a new taxon, tentatively designated Negevirus. Their closest but still distant relatives are citrus leposis virus C (CiLV-C) and viruses in the genus Cilevirus, which are mite-transmitted plant viruses. The negeviruses replicate rapidly and to high titer (up to 10(10) PFU/ml) in mosquito cells, producing extensive cytopathic effect and plaques, but they do not appear to replicate in mammalian cells or mice. A discussion follows on their possible biological significance and effect on mosquito vector competence for arboviruses