A glacial lake outburst floods hazard assessment in the Patagonian Andes combining inventory data and case-studies.

We present a glacial-related lake inventory for a region spanning 41.5° - 47° S in Patagonian Andes, where information on past glacier lake outburst floods (GLOF's) has hitherto remained significantly underreported. Analyzing remotely sensed images, we obtained data on 702 glacial-related lakes. Through detailed geomorphic assessments and manual supervision, we revised current inventories and added 35 GLOFs triggered from moraine/bedrock dammed lakes failures. The regional GLOF inventory presented contains information on 71 historical failures of moraine/bedrock dammed glacial lakes. From this database we analyzed outburst timing and managed to constrain 37 events occurrences within a period of 1 year. Around 40 % of them have occurred since the early 2000's, most of them originating from lakes probably formed as a delayed response to the glacial retreat imposed by the end of the Little Ice Age. On the other hand, we analyzed meteorological conditions for a sub-set of 10 events constrained within a 10-days period, finding a strong link between atmospheric rivers, cut-off lows impacting the southern Andes, and GLOFs. Only one case is likely to have been triggered by a Mw 4.9 earthquake. Based on topographic potential for avalanching, we estimated GLOF hazard potential, recognizing at least 3 subregions with high hazard, which moreover can be highly susceptible to climate conditions that regionally affect GLOF occurrence.

Prevalencia de anemia ferropénica en niños pre-escolares y escolares con necesidades básicas insatisfechas / Prevalence of iron deficiency anemia in a group of pre-school and school children, living in conditions of poverty

Iron deficiency is common during the first years of life. Yet, there is a paucity of data on scholar children. Our main objective was to estimate the prevalence of ferropenic anemia in children 3 to 12 years of age living under conditions of poverty. A total of 323 children were included, 171 attended to a day care institution (group A) and 152 were from the same community but not attended in the day care institution (group B). Hemoglobin (Hb), medium corpuscular volume (MCV) and serum ferritin (SF) were measured in all children. In those with Hb < or = 11 g/dl and/or MCV < or = 73 fl and/or SF < or = 15 microg/l, transferrin saturation (TS) and soluble transferrin receptors (sTR) were also measured. Iron deficiency was defined as SF < or = 15 mg/l and ferropenic anemia was defined as Hb < or = 11 g/dl or MCV < or = 73 fl with sTR > or = 38 mmol/l and SF < or = 10 microg/l or TS < or = 10%. There were no differences between the groups regarding age, weight, height, education, gender and housing conditions. Mean hemoglobin level was 12.6 g/dl (group A: 12.4 g/dl vs. group B: 12.7 g/dl; p=0.012), and mean SF was 45 mg/l, without significant differences between groups. Prevalence of iron deficiency anemia was 2.5% (8/323) and iron deficiency was 4.4% (14/317), without significant differences between groups. These results persisted after controlling for confounding variables. In this group of children living under conditions of poverty in Argentina, iron deficiency anemia was uncommon. We attribute this phenomenon to local affordability of some inexpensive cuts of red meat.

Prevalencia de anemia ferropénica en niños pre-escolares y escolares con necesidades básicas insatisfechas / Prevalence of iron deficiency anemia in a group of pre-school and school children, living in conditions of poverty

Iron deficiency is common during the first years of life. Yet, there is a paucity of data on scholar children. Our main objective was to estimate the prevalence of ferropenic anemia in children 3 to 12 years of age living under conditions of poverty. A total of 323 children were included, 171 attended to a day care institution (group A) and 152 were from the same community but not attended in the day care institution (group B). Hemoglobin (Hb), medium corpuscular volume (MCV) and serum ferritin (SF) were measured in all children. In those with Hb < or = 11 g/dl and/or MCV < or = 73 fl and/or SF < or = 15 microg/l, transferrin saturation (TS) and soluble transferrin receptors (sTR) were also measured. Iron deficiency was defined as SF < or = 15 mg/l and ferropenic anemia was defined as Hb < or = 11 g/dl or MCV < or = 73 fl with sTR > or = 38 mmol/l and SF < or = 10 microg/l or TS < or = 10%. There were no differences between the groups regarding age, weight, height, education, gender and housing conditions. Mean hemoglobin level was 12.6 g/dl (group A: 12.4 g/dl vs. group B: 12.7 g/dl; p=0.012), and mean SF was 45 mg/l, without significant differences between groups. Prevalence of iron deficiency anemia was 2.5% (8/323) and iron deficiency was 4.4% (14/317), without significant differences between groups. These results persisted after controlling for confounding variables. In this group of children living under conditions of poverty in Argentina, iron deficiency anemia was uncommon. We attribute this phenomenon to local affordability of some inexpensive cuts of red meat.(AU)

Virus sincicial respiratorio en menores de 5 años hospitalizados con infección respiratoria aguda baja / Respiratory syncitial virus in children under 5 years of age with acute lower respiratory infections

Entre julio 1988 y septiembre 1989, durante el período invernal, se investigó la presencia de Virus Sincicial Respiratorio (VSR) en 150niños menores de 5 años con infección respiratoria aguda (IRA) del tracto inferior (bronquiolitis: 56 por ciento; neumonías: 23 por ciento; bronquitis: 21 por ciento) por medio de un método rápido (inmunofluorescencia indirecta) sobre células del aspirado nasofaríngeo obtenido por succión con bomba de vacío. Se detectó antígeno de VSR en el 21,33 por ciento de los casos estudiados. El 25 por ciento de las bronquiolitis, el 17,6 por ciento de las neumonías y el 15,6 por ciento de las bronquitis resultaron positivas para VSR. La mayor frecuencia de positividad en bronquiolitis fue estadísticamente significativa (p<0,01). En neumonías se observó una disminución de la positividad a medida que aumentaba la edad. La distribución por grupo etáreo de los resultados positivos, independientemente del cuadro clínico, mostró una mayor frecuencia de VSR en menores de 23 meses. No se detectó diferencia significativa con respecto al sexo, estado nutricional y vacunación en pacientes con o sin VSR. En el grupo de 0-5 meses, el 42 por ciento de los casos positivos correspondió a menores de 30 días de vida. En 4/5 neonatos con VSR y en 3/12 menores de 12 meses con VSR se detectó la adquisición intrafamiliar de esta infección ya que se registró internación previa de hermanos con VSR en nuestro servicio. Se sugiere la necesidad de contar con métodos rápidos de estudio de la etiología viral en las IRAs a nivel hospitalario, lo que permitirá implementar estrategias más sólidas de control y tratamiento

Virus sincicial respiratorio en menores de 5 años hospitalizados con infección respiratoria aguda baja / Respiratory syncitial virus in children under 5 years of age with acute lower respiratory infections

Entre julio 1988 y septiembre 1989, durante el período invernal, se investigó la presencia de Virus Sincicial Respiratorio (VSR) en 150niños menores de 5 años con infección respiratoria aguda (IRA) del tracto inferior (bronquiolitis: 56 por ciento; neumonías: 23 por ciento; bronquitis: 21 por ciento) por medio de un método rápido (inmunofluorescencia indirecta) sobre células del aspirado nasofaríngeo obtenido por succión con bomba de vacío. Se detectó antígeno de VSR en el 21,33 por ciento de los casos estudiados. El 25 por ciento de las bronquiolitis, el 17,6 por ciento de las neumonías y el 15,6 por ciento de las bronquitis resultaron positivas para VSR. La mayor frecuencia de positividad en bronquiolitis fue estadísticamente significativa (p<0,01). En neumonías se observó una disminución de la positividad a medida que aumentaba la edad. La distribución por grupo etáreo de los resultados positivos, independientemente del cuadro clínico, mostró una mayor frecuencia de VSR en menores de 23 meses. No se detectó diferencia significativa con respecto al sexo, estado nutricional y vacunación en pacientes con o sin VSR. En el grupo de 0-5 meses, el 42 por ciento de los casos positivos correspondió a menores de 30 días de vida. En 4/5 neonatos con VSR y en 3/12 menores de 12 meses con VSR se detectó la adquisición intrafamiliar de esta infección ya que se registró internación previa de hermanos con VSR en nuestro servicio. Se sugiere la necesidad de contar con métodos rápidos de estudio de la etiología viral en las IRAs a nivel hospitalario, lo que permitirá implementar estrategias más sólidas de control y tratamiento (AU)

[Intracerebral infection of athymic mice with an attenuated strain of Junín virus]. / Infección intracerebral de ratones atímicos con una cepa atenuada de virus Junín.

Infection of newborn immunocompetent (nu/+) mice with the XJ prototype strain of Junin virus, etiological agent of Argentine Hemorrhagic Fever, produces a lethal meningo-encephalitis due to cellular immune response. The same strain inoculated into athymic (nu/nu) mice produces an asymptomatic persistent infection. The purpose of this work was to determine the nu/nu mice response when infected with XJCl3, an attenuated Junin virus strain, since this strain behaves differently to the pathogenic prototype in various experimental hosts and humans. Fifty five suckling nu/nu mice and 45 nu/+ were inoculated intracerebrally with 10(3) PFU of the XJCl3 strain. Twenty nu/nu and 20 nu/+ were kept as uninoculated controls. Similar percentages of mortality were recorded for nu/nu and nu/+ infected animals (86 and 87%). In contrast, no morbi-mortality was detected in control animals which were kept in the same animal room. High virus titers were detected in brains and lungs of infected nu/nu at 7, 14, 21 and 70 days post-infection(pi). Virus titers in blood were 1 log lower than those found in organs. Immunohistochemical studies of brains showed viral antigen in the cytoplasm of cortical neurons at 21 and 70 days pi. An interstitial pneumonitis was detected in lungs of infected nu/nu at 7 and 21 days pi, while no lesions were observed in brains and spleens. Results show that the XJl3 strain behaves in a very different way in newborn nu/nu mice as the XJ prototype strain. Further studies are necessary to determine the pathogenic mechanisms involved.

Infección intracerebral de ratones atímicos con una cepa atenuada de virus Junín. / [Intracerebral infection of athymic mice with an attenuated strain of Junín virus]

Infection of newborn immunocompetent (nu/+) mice with the XJ prototype strain of Junin virus, etiological agent of Argentine Hemorrhagic Fever, produces a lethal meningo-encephalitis due to cellular immune response. The same strain inoculated into athymic (nu/nu) mice produces an asymptomatic persistent infection. The purpose of this work was to determine the nu/nu mice response when infected with XJCl3, an attenuated Junin virus strain, since this strain behaves differently to the pathogenic prototype in various experimental hosts and humans. Fifty five suckling nu/nu mice and 45 nu/+ were inoculated intracerebrally with 10(3) PFU of the XJCl3 strain. Twenty nu/nu and 20 nu/+ were kept as uninoculated controls. Similar percentages of mortality were recorded for nu/nu and nu/+ infected animals (86 and 87

). In contrast, no morbi-mortality was detected in control animals which were kept in the same animal room. High virus titers were detected in brains and lungs of infected nu/nu at 7, 14, 21 and 70 days post-infection(pi). Virus titers in blood were 1 log lower than those found in organs. Immunohistochemical studies of brains showed viral antigen in the cytoplasm of cortical neurons at 21 and 70 days pi. An interstitial pneumonitis was detected in lungs of infected nu/nu at 7 and 21 days pi, while no lesions were observed in brains and spleens. Results show that the XJl3 strain behaves in a very different way in newborn nu/nu mice as the XJ prototype strain. Further studies are necessary to determine the pathogenic mechanisms involved.

[Rapid serologic diagnosis of Argentinian hemorrhagic fever in whole blood]. / Diagnóstico serológico rápido de fiebre hemorrágica Argentina en sangre entera.

The usefulness of a method for detection of antibodies against Junin virus in whole blood was tested. N: NIH adult mice were inoculated with 10(3) PFU of attenuated XJ-Clon 3 Junin virus strain by intraperitoneal route and blood was obtained by retro-orbital puncture at 21 days post-infection. One blood aliquot (50 microliters) was collected in tubes containing a stabilizer solution for whole blood and another was processed for serum obtention. Immunofluorescent antibodies were tested on spot slides of a BHK/21 cell line persistently infected with Junin virus. High antibody titers (1/64 to 1/256) were detected in both whole blood and serum, with 66% coincidence between both procedures. These results show that the method of detection of antibodies in whole blood would be useful to test quickly for anti-Junin virus antibodies in seroepidemiologic studies, in endemic areas.

Diagnóstico serológico rápido de fiebre hemorrágica Argentina en sangre entera. / [Rapid serologic diagnosis of Argentinian hemorrhagic fever in whole blood]

The usefulness of a method for detection of antibodies against Junin virus in whole blood was tested. N: NIH adult mice were inoculated with 10(3) PFU of attenuated XJ-Clon 3 Junin virus strain by intraperitoneal route and blood was obtained by retro-orbital puncture at 21 days post-infection. One blood aliquot (50 microliters) was collected in tubes containing a stabilizer solution for whole blood and another was processed for serum obtention. Immunofluorescent antibodies were tested on spot slides of a BHK/21 cell line persistently infected with Junin virus. High antibody titers (1/64 to 1/256) were detected in both whole blood and serum, with 66

coincidence between both procedures. These results show that the method of detection of antibodies in whole blood would be useful to test quickly for anti-Junin virus antibodies in seroepidemiologic studies, in endemic areas.