Dietary Habits of the Common Rodents in an Agrecosystem in Argentina

Dietary habits of five common rodents in agroecosystems on the central Argentine Pampa were studied for 15 months using microhistological analysis of stomach contents. All five rodent species were omnivorous, but proportions of major dietary items (arthropods, dicot leaves and seeds, monocot leaves and seeds) varied among species and seasons. Akodon azarae largely was entomophagous; arthropods formed 41-62% of the diet in all seasons. The other four species (Calomys musculinus, Calomys laucha, Bolomys obscurus, and Oligoryzomys flavescens) consumed most diet items throughout the year, but relative proportions varied among seasons. Leaves formed a relatively minor proportion of the diet (12- 16% overall for all species) throughout the year. All species except A. azarae consumed higher quantities of seeds (50-73% of stomach volume) than arthropods (15-35%) during autumn and winter but switched to higher quantities of arthropods (30-53%) in spring and summer. Diet breadth was narrower and overlap generally highest during winter when all species were forced to subsist on a reduced set of available resources. Of 28 plant species with \u3e2% cover in the environment, 25 were identified in stomachs of one or more of the five rodent species. The most important plant species in the diet were corn and soybeans (mostly grain), seed of Johnson grass (Sorghum halepense), chickweed (Stellaria media), and Amaranthus. High consumption of arthropods, especially by A. azarae, contraindicates the broad-scale use of rodenticides until the role of that rodent species in the control of pest insects can be ascertained

Dietary Habits of the Common Rodents in an Agrecosystem in Argentina

Dietary habits of five common rodents in agroecosystems on the central Argentine Pampa were studied for 15 months using microhistological analysis of stomach contents. All five rodent species were omnivorous, but proportions of major dietary items (arthropods, dicot leaves and seeds, monocot leaves and seeds) varied among species and seasons. Akodon azarae largely was entomophagous; arthropods formed 41-62% of the diet in all seasons. The other four species (Calomys musculinus, Calomys laucha, Bolomys obscurus, and Oligoryzomys flavescens) consumed most diet items throughout the year, but relative proportions varied among seasons. Leaves formed a relatively minor proportion of the diet (12- 16% overall for all species) throughout the year. All species except A. azarae consumed higher quantities of seeds (50-73% of stomach volume) than arthropods (15-35%) during autumn and winter but switched to higher quantities of arthropods (30-53%) in spring and summer. Diet breadth was narrower and overlap generally highest during winter when all species were forced to subsist on a reduced set of available resources. Of 28 plant species with \u3e2% cover in the environment, 25 were identified in stomachs of one or more of the five rodent species. The most important plant species in the diet were corn and soybeans (mostly grain), seed of Johnson grass (Sorghum halepense), chickweed (Stellaria media), and Amaranthus. High consumption of arthropods, especially by A. azarae, contraindicates the broad-scale use of rodenticides until the role of that rodent species in the control of pest insects can be ascertained

Clusters of Hantavirus Infection, Southern Argentina

Person-to-person transmission should be suspected when Andes virus case-patients are linked

Living with the COVID-19 pandemic: act now with the tools we have.

Fil: Bedford, Juliet. Anthrologica, Oxfordshire; Reino Unido.Fil: Enria, Delia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Giesecke, Johan. Karolinska Institute, Stockholm; Suecia.Fil: Heymann, David L. Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine; Reino Unido.Fil: Ihekweazu, Chikwe. Nigeria Centre for Disease Control; Nigeria.Fil: Kobinger, Gary. Infectious Disease Research Centre, Université Laval, Faculty of Medicine; Canada.Fil: Lane, H Clifford. National Institute of Allergy and Infectious Diseases; Estados Unidos.Fil: Memish, Ziad A. J W Lee Center for Global Medicine, SNU College of Medicine, Department of Internal Medicine, Seoul National University Hospital; Corea del Sur.Fil: Oh, Myoung-Don. J W Lee Center for Global Medicine, SNU College of Medicine, Department of Internal Medicine, Seoul National University Hospital; Corea del Sur.Fil: Sall, Amadou Alpha. Institut Pasteur de Dakar; Senegal.Fil: Ungchusak, Kumnuan. Ministry of Health, Department of Diseases Control; Tailandia.Fil: Wieler, Lothar H. Robert Koch Institute; Alemania.The responses of countries to the COVID-19 pandemic have been disparate.1, 2 Many countries are reopening workplaces, schools, and social gatherings and striving to adapt their economies and resume international travel. Other countries are attempting to suppress transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by again restricting businesses, industries, and schools while hoping for future COVID-19 vaccines or treatments. The Strategic and Technical Advisory Group for Infectious Hazards (STAG-IH), the independent advisory group to the WHO Health Emergencies Programme, has reviewed information from countries around the world and has concluded that the most sound approach on the basis of current understanding is to deploy long-term strategies with a focus on preventing amplification of transmission, protecting those most at risk of severe illness, and supporting research to better understand the virus, the disease, and people's responses to them

Vaccine-elicited receptor-binding site antibodies neutralize two New World hemorrhagic fever arenaviruses

While five arenaviruses cause human hemorrhagic fevers in the Western Hemisphere, only Junin virus (JUNV) has a vaccine. The GP1 subunit of their envelope glycoprotein binds transferrin receptor 1 (TfR1) using a surface that substantially varies in sequence among the viruses. As such, receptor-mimicking antibodies described to date are type-specific and lack the usual breadth associated with this mode of neutralization. Here we isolate, from the blood of a recipient of the live attenuated JUNV vaccine, two antibodies that cross-neutralize Machupo virus with varying efficiency. Structures of GP1–Fab complexes explain the basis for efficient cross-neutralization, which involves avoiding receptor mimicry and targeting a conserved epitope within the receptor-binding site (RBS). The viral RBS, despite its extensive sequence diversity, is therefore a target for cross-reactive antibodies with activity against New World arenaviruses of public health concern

Vaccine-elicited receptor-binding site antibodies neutralize two New World hemorrhagic fever arenaviruses

While five arenaviruses cause human hemorrhagic fevers in the Western Hemisphere, only Junin virus (JUNV) has a vaccine. The GP1 subunit of their envelope glycoprotein binds transferrin receptor 1 (TfR1) using a surface that substantially varies in sequence among the viruses. As such, receptor-mimicking antibodies described to date are type-specific and lack the usual breadth associated with this mode of neutralization. Here we isolate, from the blood of a recipient of the live attenuated JUNV vaccine, two antibodies that cross-neutralize Machupo virus with varying efficiency. Structures of GP1–Fab complexes explain the basis for efficient cross-neutralization, which involves avoiding receptor mimicry and targeting a conserved epitope within the receptor-binding site (RBS). The viral RBS, despite its extensive sequence diversity, is therefore a target for cross-reactive antibodies with activity against New World arenaviruses of public health concern

Protective efficacy of a live attenuated vaccine against Argentine hemorrhagic fever. AHF Study Group

Fil: Maiztegui, Julio I. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: McKee Jr, K. T. Womack Army Medical Center, Fort Bragg, North Carolina; Estados Unidos.Fil: Barrera Oro, J G. ANLIS Dr.C.G.Malbrán; Argentina.Fil: Harrison, L H. University of Pittsburgh Graduate School of Public Health,Pittsburgh, Pennsylvania; Estados Unidos.Fil: Gibbs, P H. Division of Disease Assessment, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland 21701; Estados Unidos.Fil: Feuillade, María Rosa. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Enria, Delia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Briggiler, Ana M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Levis, Silvana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Ambrosio, Ana María. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Halsey, N A. Department of International Health, Johns Hopkins Medical Institutions, Baltimore, Maryland; Estados Unidos.Fil: Peters, C J. Special Pathogens Branch, Centers for Disease Control, Atlanta, Georgia; Estados Unidos.Argentine hemorrhagic fever (AHF), caused by the arenavirus Junin, is a major public health problem among agricultural workers in Argentina. A prospective, randomized, double-blind, placebo-controlled, efficacy trial of Candid 1, a live attenuated Junin virus vaccine, was conducted over two consecutive epidemic seasons among 6500 male agricultural workers in the AHF-endemic region. Twenty-three men developed laboratory-confirmed AHF during the study; 22 received placebo and 1 received vaccine (vaccine efficacy 95%; 95% confidence interval [CI], 82%-99%). Three additional subjects in each group developed laboratory-confirmed Junin virus infection associated with mild illnesses that did not fulfill the clinical case definition for AHF, yielding a protective efficacy for prevention of any illness associated with Junin virus infection of 84% (95% CI, 60%-94%). No serious adverse events were attributed to vaccination. Candid 1, the first vaccine for the prevention of illness caused by an arenavirus, is safe and highly efficacious

Evaluation of commercially available diagnostic tests for the detection of dengue virus NS1 antigen and anti-dengue virus IgM antibody.

Commercially available diagnostic test kits for detection of dengue virus (DENV) non-structural protein 1 (NS1) and anti-DENV IgM were evaluated for their sensitivity and specificity and other performance characteristics by a diagnostic laboratory network developed by World Health Organization (WHO), the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR) and the Pediatric Dengue Vaccine Initiative (PDVI). Each network laboratory contributed characterized serum specimens for the panels used in the evaluation. Microplate enzyme-linked immunosorbent assay (ELISA) and rapid diagnostic test (RDT formats) were represented by the kits. Each ELISA was evaluated by 2 laboratories and RDTs were evaluated by at least 3 laboratories. The reference tests for IgM anti-DENV were laboratory developed assays produced by the Armed Forces Research Institute for Medical Science (AFRIMS) and the Centers for Disease Control and Prevention (CDC), and the NS1 reference test was reverse transcriptase polymerase chain reaction (RT-PCR). Results were analyzed to determine sensitivity, specificity, inter-laboratory and inter-reader agreement, lot-to-lot variation and ease-of-use. NS1 ELISA sensitivity was 60-75% and specificity 71-80%; NS1 RDT sensitivity was 38-71% and specificity 76-80%; the IgM anti-DENV RDTs sensitivity was 30-96%, with a specificity of 86-92%, and IgM anti-DENV ELISA sensitivity was 96-98% and specificity 78-91%. NS1 tests were generally more sensitive in specimens from the acute phase of dengue and in primary DENV infection, whereas IgM anti-DENV tests were less sensitive in secondary DENV infections. The reproducibility of the NS1 RDTs ranged from 92-99% and the IgM anti-DENV RDTs from 88-94%

An outbreak of hantavirus pulmonary syndrome, Chile, 1997

Fil: Toro, Jorge. Ministry of Health; Chile.Fil: Vega, Jeanette D. Pan American Health Organization; Chile.Fil: Khan, Ali S. Centers for Disease Control and Prevention; Estados Unidos.Fil: Mills, James N. Centers for Disease Control and Prevention; Estados Unidos.Fil: Padula, Paula. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Terry, William. Centers for Disease Control and Prevention; Estados Unidos.Fil: Yadón, Zaida. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Valderrama, Rosa. Aysen Region XI Health Service; Chile.Fil: Ellis, Barbara A. Centers for Disease Control and Prevention; Estados Unidos.Fil: Pavletic, Carlos. Ministry of Health; Chile.Fil: Cerda, Rodrigo. Pan American Health Organization; Chile.Fil: Zaki, Sherif. Centers for Disease Control and Prevention; Estados Unidos.Fil: Wun-Ju, Shieh. Centers for Disease Control and Prevention; Estados Unidos.Fil: Meyer, Richard. Centers for Disease Control and Prevention; Estados Unidos.Fil: Tapia, Mauricio. Coyhaique Regional Hospital; Chile.Fil: Mansilla, Carlos. Coyhaique Regional Hospital; Chile.Fil: Baro, Michel. Llanchipal Health Services; Chile.Fil: Vergara, Jose A. Llanchipal Health Services; Chile.Fil: Concha, Marisol. Ministry of Health; Chile.Fil: Calderón, Gladys. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Enria, Delia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Peters, C.J. Centers for Disease Control and Prevention; Estados Unidos.Fil: Ksiazek, Thomas G. Centers for Disease Control and Prevention; Estados Unidos.An outbreak of 25 cases of Andes virus-associated hantavirus pulmonary syndrome (HPS) was recognized in southern Chile from July 1997 through January 1998. In addition to the HPS patients, three persons with mild hantaviral disease and one person with asymptomatic acute infection were identified. Epidemiologic studies suggested person-to-person transmission in two of three family clusters. Ecologic studies showed very high densities of several species of sigmodontine rodents in the area

An outbreak of hantavirus pulmonary syndrome, Chile, 1997

Fil: Toro, Jorge. Ministry of Health; Chile.Fil: Vega, Jeanette D. Pan American Health Organization; Chile.Fil: Khan, Ali S. Centers for Disease Control and Prevention; Estados Unidos.Fil: Mills, James N. Centers for Disease Control and Prevention; Estados Unidos.Fil: Padula, Paula. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Terry, William. Centers for Disease Control and Prevention; Estados Unidos.Fil: Yadón, Zaida. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Valderrama, Rosa. Aysen Region XI Health Service; Chile.Fil: Ellis, Barbara A. Centers for Disease Control and Prevention; Estados Unidos.Fil: Pavletic, Carlos. Ministry of Health; Chile.Fil: Cerda, Rodrigo. Pan American Health Organization; Chile.Fil: Zaki, Sherif. Centers for Disease Control and Prevention; Estados Unidos.Fil: Wun-Ju, Shieh. Centers for Disease Control and Prevention; Estados Unidos.Fil: Meyer, Richard. Centers for Disease Control and Prevention; Estados Unidos.Fil: Tapia, Mauricio. Coyhaique Regional Hospital; Chile.Fil: Mansilla, Carlos. Coyhaique Regional Hospital; Chile.Fil: Baro, Michel. Llanchipal Health Services; Chile.Fil: Vergara, Jose A. Llanchipal Health Services; Chile.Fil: Concha, Marisol. Ministry of Health; Chile.Fil: Calderón, Gladys. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Enria, Delia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Peters, C.J. Centers for Disease Control and Prevention; Estados Unidos.Fil: Ksiazek, Thomas G. Centers for Disease Control and Prevention; Estados Unidos.An outbreak of 25 cases of Andes virus-associated hantavirus pulmonary syndrome (HPS) was recognized in southern Chile from July 1997 through January 1998. In addition to the HPS patients, three persons with mild hantaviral disease and one person with asymptomatic acute infection were identified. Epidemiologic studies suggested person-to-person transmission in two of three family clusters. Ecologic studies showed very high densities of several species of sigmodontine rodents in the area