Orthohantavirus Infection in Two Rodent Species that Inhabit Wetlands in Argentina.

Previous research conducted in central-east region of Argentina recorded potential orthohantavirus host rodents in diverse environments, but no research has focused particularly on islands, the environments that present the greatest risk to humans. For this reason, the aims of this research were to determine the orthohantavirus host in the rodent community focused on islands of Paraná River Delta, central-east region of Argentina, to identify temporal and spatial factors associated with orthohantavirus prevalence variations, to compare the functional traits of seropositive and seronegative rodents, and to explore the association between orthohantavirus prevalence and rodent community characteristics between August 2014 and May 2018. With a trapping effort of 14,600 trap-nights, a total of 348 sigmodontine rodent specimens belonging to seven species were captured 361 times. The overall antibody prevalence was 4.9%. Particularly, 14.9% of Oligoryzomys flavescens and 1.5% of Oxymycterus rufus, mainly reproductively active adult males, had antibodies against orthohantavirus. Even though O. flavescens inhabit all islands, our results suggest spatial heterogeneity in the viral distribution, with two months after periods of low temperature presenting increases in seroprevalence. This could be a response to the increased proportion of adults present in the rodent population. In addition, an association was found between the high seroprevalence and the diversity of the rodent assemblage. We also found 1.5% of O. rufus exposed to orthohantavirus, which shows us that further investigation of the ecology of the virus is needed to answer whether this species act as a spillover or a new competent host.

Modelling relative abundance of Oligoryzomys flavescens, an Orthohantavirus reservoir, in an endemic hantavirus pulmonary syndrome zone.

Hantavirus pulmonary syndrome (HPS) is a zoonotic emerging infectious disease caused by New World orthohantaviruses (family Hantaviridae) hosted by rodents of the family Cricetidae. In Argentina, one of its main hosts is the sigmodontine rodent Oligoryzomys flavescens, a widely distributed mouse of the Pampas, Delta and Espinal ecoregions of central-east Argentina. Because the abundance of the reservoir and its proportion in the rodent community affects both virus prevalence and human exposure risk, its estimation throughout its known geographical distribution is of key importance for the design of public health strategies to prevent HPS. The aim of this study was therefore to model the relative abundance of O. flavescens in most of the Pampas ecoregion within Buenos Aires Province, Argentina, where hantavirus pulmonary syndrome is endemic. To do this we used owl-pellet samples collected between 2006 and 2008 from 51 sites distributed throughout most of Buenos Aires province. Mammalian prey in each pellet was identified to the lowest possible taxonomic level by examination of the skulls, dentaries and molars. We modelled the frequency of O. flavescens found in each sample as a function of climatic, environmental, and topographic data of each site. The two best models were applied to a Geo referential Information System to build maps of estimated frequency (as a proxy of relative abundance) within Buenos Aires province. Estimated relative abundance of O. flavescens in Buenos Aires province was significantly associated with annual mean temperature, annual precipitation and presence of freshwater bodies, and varied among sub-regions, with the Inland and Rolling Pampas being the regions with highest frequencies. Knowing in which areas O. flavescens abundance is expected to be higher can be used to concentrate limited sanitary efforts in those areas that are most needed in order to reduce transmission and increase detection.

Serological Evidence of Human Orthohantavirus Infections in Barbados, 2008 to 2016.

BACKGROUND: Hantavirus pulmonary syndrome (HPS) is well-known in South and North America; however, not enough data exist for the Caribbean. The first report of clinical orthohantavirus infection was obtained in Barbados, but no other evidence of clinical orthohantavirus infections among adults in the Caribbean has been documented. METHODS: Using enzyme linked immunosorbent assay (ELISA) tests followed by confirmatory testing with immunofluorescent assays (IFA), immunochromatographic (ICG) tests, and pseudotype focus reduction neutralization tests (pFRNT), we retrospectively and prospectively detected orthohantavirus-specific antibodies among patients with febrile illness in Barbados. RESULTS: The orthohantavirus prevalence rate varied from 5.8 to 102.6 cases per 100,000 persons among febrile patients who sought medical attention annually between 2008 and 2016. Two major orthohantavirus epidemics occurred in Barbados during 2010 and 2016. Peak orthohantavis infections were observed observed during the rainy season (August) and prevalence rates were significantly higher in females than males and in patients from urban parishes than rural parishes. CONCLUSIONS: Orthohantavirus infections are still occurring in Barbados and in some patients along with multiple pathogen infections (CHIKV, ZIKV, DENV and Leptospira). Orthohantavirus infections are more prevalent during periods of high rainfall (rainy season) with peak transmission in August; females are more likely to be infected than males and infections are more likely among patients from urban rather than rural parishes in Barbados.

Measuring Treatment Response in Pediatric Trichotillomania: A Meta-Analysis of Clinical Trials.

Objectives: In clinical trials of pediatric trichotillomania (TTM), three instruments are typically employed to rate TTM severity: (1) the Massachusetts General Hospital Hair Pulling Scale (MGH-HPS), (2) the National Institute of Mental Health Trichotillomania Severity Scale (NIMH-TSS), and (3) the Trichotillomania Scale for Children (TSC). These instruments lack standardized definitions of treatment response, which lead researchers to determine their own definitions of response post hoc and potentially inflate results. We performed a meta-analysis to provide empirically determined accuracy measures for percentage reduction cut points in these three instruments. Methods: MEDLINE was searched for TTM clinical trials. A total of 67 studies were initially identified, but only 5 were clinical trials focused on TTM in pediatric populations and therefore were included in this meta-analysis (n = 180). A Clinical Global Impressions Improvement score ≤2 was used to define clinical response. Receiver operating characteristic principles were employed to determine accuracy measures for percentage reduction cut points on each one of the instruments. Meta-DiSc software was employed to provide pooled accuracy measures for each cut point for each instrument. The Youden Index and the distance to corner methods were used to determine the optimal cut point. Results: The optimal cut points to determine treatment response were a 45% reduction on the MGH-HPS (Youden Index 0.40, distance to corner 0.20), a 35% reduction on the NIMH-TSS (Youden Index 0.42, distance to corner 0.17), a 25% reduction on the TSC child version (TSC-C; Youden Index 0.40, distance to corner 0.18), and a 45% (distance to corner 0.30) or 50% reduction (Youden Index 0.33) on the TSC parent version (TSC-P). The TSC-C had less discriminative ability at determining response in younger children in comparison to older children; no age-related differences were observed on the TSC-P. Conclusions: This study provides empirically determined cut points of treatment response on three instruments that rate TTM severity. These data-driven cut points will benefit future research on pediatric TTM.

Serum LPS Associated with Hantavirus and Dengue Disease Severity in Barbados.

Hantavirus and dengue virus (DENV) infections are caused by RNA viruses which infect immune systems' cells including monocytes, macrophages and dendritic cells and occur year-round in Barbados. A retrospective serological study (2008-2015) was conducted on hantavirus and dengue patient sera confirmed by IgM and IgG ELISA, NS1 and RT-PCR using Limulus amoebocyte lysate (LAL) kinetic turbidimetric method to determine serum endotoxin levels. Hantavirus patients were categorized into two groups, namely (a) hospitalized and (b) non-hospitalized. Dengue patients were categorized into 3 groups using 2009 WHO dengue guidelines (a) severe dengue (SD), (b) hospitalized non-severe dengue (non-SD) and (c) non-hospitalized non-SD. Statistical analyses were conducted to determine the association of endotoxin levels with hantavirus disease severity based on hospitalization and dengue disease severity. Serum endotoxin levels are associated with hantavirus disease severity and hospitalization and dengue disease severity (p < 0.01). Similar studies have found an association of serum endotoxin levels with dengue disease severity but never with hantavirus infection. Co-detection of hantavirus- and DENV-specific IgM in some patients were observed with elevated serum endotoxin levels. In addition, previous studies observed hantavirus replication in the gut of patients, gastrointestinal tract as a possible entry route of infection and evidence of microbial translocation and its impact on hantavirus disease severity. A significant correlation of serum endotoxin and hantavirus disease severity and hospitalization in hantavirus infected patients is reported for the first time ever. In addition, serum endotoxin levels correlated with dengue disease severity. This study adds further support to the role of endotoxin in both hantavirus and dengue virus infection and disease severity and its role as a possible therapeutic target for viral haemorrhagic fevers (VHFs).

How the fluctuations of water levels affect populations of invasive bivalve Corbicula fluminea (Müller, 1774) in a Neotropical reservoir? / Como a flutuação dos níveis da água afetam as populações do bivalve invasor Corbicula fluminea (Müller, 1774) em um reservatório neotropical?

Corbicula fluminea is an invasive bivalve responsible for several environmental and financial problems around the globe. Despite the invasive potential of this species, it suffers certain restrictions in lentic environments due to natural phenomena that significantly affect its population structure (e.g. water column fluctuation and sunlight exposure). The present study addresses how temporal decline of the water level in a Neotropical reservoir and exposure to sunlight affect the population structure of C. fluminea. Samplings were carried out twice in the reservoir of Furnas Hydroelectric Power Station (HPS) (Minas Gerais, Brazil), in 2011 and 2012. Population density, spatial distribution and mean shell length of C. fluminea were estimated for each year after sampling in 51 quadrats (0.0625m2) placed on three transects at different distances along the reservoir margins (0, 10 and 20 m from a fixed-point). We observed a predominance of C. fluminea in both years, with a simultaneous gradual decrease in density and richness of native species in the sampling area. Significant differences in density of C. fluminea were registered at different distances from the margin, and are related to the temporal variability of physical conditions of the sediment and water in these environments. We also registered a trend toward an increase in the density and aggregation of C. fluminea as we moved away from the margin, due to the greater stability of these areas (>10 m). The mean shell length of C. fluminea showed significant difference between the distinct distances from the margin and during the years, as well as the interaction of these factors (Distances vs.Years). These results were associated with the reproductive and invasive capacity of this species. This study reveals that these temporal events (especially water column fluctuation) may cause alterations in density, spatial distribution and mean shell length of C. fluminea and the composition of the native malacofauna in Neotropical lentic environments.(AU)

Corbicula fluminea é um bivalve invasor, responsável por inúmeros problemas ambientais e econômicos ao redor do mundo. Apesar de sua capacidade de invasão, a espécie sofre certas restrições devido a fenômenos naturais em ambientes lênticos, afetando significativamente sua estrutura populacional (e.g. flutuação do nível da água e a exposição à luz solar). O presente trabalho avaliou como o decréscimo temporal do nível da água de um reservatório neotropical e a exposição solar, afeta a estrutura populacional de C. fluminea. Duas amostragens foram realizadas no reservatório da Usina Hidrelétrica (UHE) de Furnas (Minas Gerais, Brasil), em 2011 e 2012. A densidade populacional, o comprimento médio e a distribuição espacial da espécie para cada ano foram estimados após amostragem em 51 quadrats (0,0625m2) dispostos em três transectos em diferentes distâncias das margens do reservatório (0, 10 e 20 m em relação a um ponto fixo). Observou-se o predomínio de C. fluminea em ambos os anos, coincidindo com o decréscimo da densidade e riqueza de espécies nativas nas áreas de amostragem. Foram registradas diferenças significativas na densidade de C. fluminea entre as distâncias da margem, sendo atribuídas principalmente à variabilidade temporal do substrato e da água desses ambientes. Registrou-se também uma tendência em aumento da densidade e agregação com o aumento da distância da margem, devido à maior estabilidade dessas áreas (>10 m). Houveram diferenças significativas no tamanho médio das conchas de C. fluminea entre às distâncias da margem e durante os anos, assim como na interação desses fatores (Distâncias vs. Anos). Tais resultados foram associados à capacidade reprodutiva e invasiva da espécie. Esse estudo revelou que eventos temporais (principalmente, a flutuação do nível da água) em ambientes lênticos neotropicais provocam alterações na densidade, tamanho médio e distribuição de C. fluminea e na composição da malacofauna nativa.(AU)

How the fluctuations of water levels affect populations of invasive bivalve Corbicula fluminea (Müller, 1774) in a Neotropical reservoir? / Como a flutuação dos níveis da água afetam as populações do bivalve invasor Corbicula fluminea (Müller, 1774) em um reservatório neotropical?

Corbicula fluminea is an invasive bivalve responsible for several environmental and financial problems around the globe. Despite the invasive potential of this species, it suffers certain restrictions in lentic environments due to natural phenomena that significantly affect its population structure (e.g. water column fluctuation and sunlight exposure). The present study addresses how temporal decline of the water level in a Neotropical reservoir and exposure to sunlight affect the population structure of C. fluminea. Samplings were carried out twice in the reservoir of Furnas Hydroelectric Power Station (HPS) (Minas Gerais, Brazil), in 2011 and 2012. Population density, spatial distribution and mean shell length of C. fluminea were estimated for each year after sampling in 51 quadrats (0.0625m2) placed on three transects at different distances along the reservoir margins (0, 10 and 20 m from a fixed-point). We observed a predominance of C. fluminea in both years, with a simultaneous gradual decrease in density and richness of native species in the sampling area. Significant differences in density of C. fluminea were registered at different distances from the margin, and are related to the temporal variability of physical conditions of the sediment and water in these environments. We also registered a trend toward an increase in the density and aggregation of C. fluminea as we moved away from the margin, due to the greater stability of these areas (>10 m). The mean shell length of C. fluminea showed significant difference between the distinct distances from the margin and during the years, as well as the interaction of these factors (Distances vs.Years). These results were associated with the reproductive and invasive capacity of this species. This study reveals that these temporal events (especially water column fluctuation) may cause alterations in density, spatial distribution and mean shell length of C. fluminea and the composition of the native malacofauna in Neotropical lentic environments.

Corbicula fluminea é um bivalve invasor, responsável por inúmeros problemas ambientais e econômicos ao redor do mundo. Apesar de sua capacidade de invasão, a espécie sofre certas restrições devido a fenômenos naturais em ambientes lênticos, afetando significativamente sua estrutura populacional (e.g. flutuação do nível da água e a exposição à luz solar). O presente trabalho avaliou como o decréscimo temporal do nível da água de um reservatório neotropical e a exposição solar, afeta a estrutura populacional de C. fluminea. Duas amostragens foram realizadas no reservatório da Usina Hidrelétrica (UHE) de Furnas (Minas Gerais, Brasil), em 2011 e 2012. A densidade populacional, o comprimento médio e a distribuição espacial da espécie para cada ano foram estimados após amostragem em 51 quadrats (0,0625m2) dispostos em três transectos em diferentes distâncias das margens do reservatório (0, 10 e 20 m em relação a um ponto fixo). Observou-se o predomínio de C. fluminea em ambos os anos, coincidindo com o decréscimo da densidade e riqueza de espécies nativas nas áreas de amostragem. Foram registradas diferenças significativas na densidade de C. fluminea entre as distâncias da margem, sendo atribuídas principalmente à variabilidade temporal do substrato e da água desses ambientes. Registrou-se também uma tendência em aumento da densidade e agregação com o aumento da distância da margem, devido à maior estabilidade dessas áreas (>10 m). Houveram diferenças significativas no tamanho médio das conchas de C. fluminea entre às distâncias da margem e durante os anos, assim como na interação desses fatores (Distâncias vs. Anos). Tais resultados foram associados à capacidade reprodutiva e invasiva da espécie. Esse estudo revelou que eventos temporais (principalmente, a flutuação do nível da água) em ambientes lênticos neotropicais provocam alterações na densidade, tamanho médio e distribuição de C. fluminea e na composição da malacofauna nativa.

Fowl adenovirus Group I as a causal agent of inclusion body hepatitis/hydropericardium syndrome (IBH/HPS) outbreak in brazilian broiler flocks / Adenovirus aviário Ggrupo I como um agente causal da síndrome da hepatite por corpúsculo de inclusão/hidropericárdio (IBH/HPS) em lotes de frangos de corte

Commercial broiler flocks from a farm located in the State of São Paulo, Brazil, presented diarrhea, depression, increased mortality and poor weight gain. Upon post-mortem examination, classical signs of Inclusion Body Hepatitis/Hydropericardium Syndrome (IBH/HPS) were observed, including enlarged pale yellow-colored livers and straw-colored liquid in the pericardial sac. In addition, gross lesions were also observed in the kidneys, pancreas, thymus, intestines and gallbladder. Samples of these organs were analyzed by PCR for the detection of the hexon gene of the Fowl Adenovirus (FAdVs) Group I. The results were positive for both flocks (A and B) assayed by PCR. The macroscopic lesions associated with the detection of FAdV Group I by PCR in several of these affected organs allowed for the identification of IBH/HPS. In fact, this is the first report in Brazil of IBH/HPS in broilers, which identifies FAdVs group I as a causal agent of the disease. These findings may contribute to the worldwide epidemiology of the adenovirus-mediated hepatitis/hydropericardium syndrome.(AU)

Lotes comerciais de frangos de uma granja localizada no Estado de São Paulo, Brasil, apresentavam diarreia, depressão, aumento de mortalidade e baixo ganho de peso. Após o exame post-mortem, sinais clássicos da síndrome de hepatite por corpúsculo de inclusão/hidropericárdio (IBH/HPS) foram observados incluindo hepatomegalia com aspecto amarelado pálido e líquido de coloração amarelo palha no saco pericárdio. Além disso, as alterações macroscópicas foram também observadas nos rins, pâncreas, timo, intestinos e vesícula biliar. Amostras destes órgãos foram analisadas pela técnica de PCR para detectar o adenovírus aviário do grupo I através do gene Hexon. Os resultados foram positivos para ambos os lotes (A e B) utilizando-se a técnica de PCR. As lesões macroscópicas associadas à detecção do adenovírus aviário do grupo I pela técnica de PCR em vários destes órgãos acometidos permitiu a identificação da síndrome de hepatite/hidropericárdio em frangos no Brasil. Ao nosso conhecimento, este é a primeira descrição da síndrome de hepatite/hidropericárdio causado por adenovírus aviário do grupo I, no Brasil. Estes achados podem contribuir com a epidemiologia mundial do adenovírus mediando a síndrome de hepatite/hidropericárdio.(AU)

Fowl adenovirus Group I as a causal agent of inclusion body hepatitis/hydropericardium syndrome (IBH/HPS) outbreak in brazilian broiler flocks / Adenovirus aviário Ggrupo I como um agente causal da síndrome da hepatite por corpúsculo de inclusão/hidropericárdio (IBH/HPS) em lotes de frangos de corte

Commercial broiler flocks from a farm located in the State of São Paulo, Brazil, presented diarrhea, depression, increased mortality and poor weight gain. Upon post-mortem examination, classical signs of Inclusion Body Hepatitis/Hydropericardium Syndrome (IBH/HPS) were observed, including enlarged pale yellow-colored livers and straw-colored liquid in the pericardial sac. In addition, gross lesions were also observed in the kidneys, pancreas, thymus, intestines and gallbladder. Samples of these organs were analyzed by PCR for the detection of the hexon gene of the Fowl Adenovirus (FAdVs) Group I. The results were positive for both flocks (A and B) assayed by PCR. The macroscopic lesions associated with the detection of FAdV Group I by PCR in several of these affected organs allowed for the identification of IBH/HPS. In fact, this is the first report in Brazil of IBH/HPS in broilers, which identifies FAdVs group I as a causal agent of the disease. These findings may contribute to the worldwide epidemiology of the adenovirus-mediated hepatitis/hydropericardium syndrome...

Lotes comerciais de frangos de uma granja localizada no Estado de São Paulo, Brasil, apresentavam diarreia, depressão, aumento de mortalidade e baixo ganho de peso. Após o exame post-mortem, sinais clássicos da síndrome de hepatite por corpúsculo de inclusão/hidropericárdio (IBH/HPS) foram observados incluindo hepatomegalia com aspecto amarelado pálido e líquido de coloração amarelo palha no saco pericárdio. Além disso, as alterações macroscópicas foram também observadas nos rins, pâncreas, timo, intestinos e vesícula biliar. Amostras destes órgãos foram analisadas pela técnica de PCR para detectar o adenovírus aviário do grupo I através do gene Hexon. Os resultados foram positivos para ambos os lotes (A e B) utilizando-se a técnica de PCR. As lesões macroscópicas associadas à detecção do adenovírus aviário do grupo I pela técnica de PCR em vários destes órgãos acometidos permitiu a identificação da síndrome de hepatite/hidropericárdio em frangos no Brasil. Ao nosso conhecimento, este é a primeira descrição da síndrome de hepatite/hidropericárdio causado por adenovírus aviário do grupo I, no Brasil. Estes achados podem contribuir com a epidemiologia mundial do adenovírus mediando a síndrome de hepatite/hidropericárdio...