Ensayo preclínico de la vacuna candid #1 producida en Argentina contra la fiebre hemorrágica Argentina

Se comparó en cobayos la seguridad, inmunogenicidad y eficacia protectora de un lote de vacuna Candid #1(C#1) fabricada en Estados Unidos de América (EE.UU.) y distintos lotes de la misma vacuna fabricados en Argentina (Arg). El lote TSI 5-1-92 (EE.UU.) y los lotes Exp Nº 3, 7A y 8A (Arg) fueron inoculados (0.5 ml, IM) en cobayos de 250-400 g. Para cada ensayo diez animales recibieron solución fisiológica y sirvieron como control. Todos fueron desafiados con la cepa patógena P23790 de virus Junin. Se registró: a) temperatura rectal, b) peso corporal, c) presencia de anticuerpos neutralizantes (AcNT) pre y post-vacunación, d) respuesta al desafío. Todos los animales vacunados desarrollaron AcNT anti virus Junin (rango = 40- 81920 y sobrevivieron al desafío. En cada grupo control 8/10 animales murieron (día 23.3 ± 5.4 post-desafío). Los cobayos resultaron idénticamente protegidos de una descarga letal de virus Junin por la vacuna importada y los diferentes lotes de C#1 producidos en Argentina.Preclinical assay of Candid #1 vaccine against Argentine Hemorrhagic Fever made in Argentina. Candid #1 vaccine against Argentine Hemorrhagic Fever produced in USA versus lots of the same vaccine made in Argentina were compared in guinea pigs regarding safety, immunogenicity and protective efficacy against a challenge with pathogenic Junin virus. Lots Nº Exp 3, 7A and 8A of Argentine origin as well as lot TSI 5-1-92 from USA were inoculated in guinea pigs of 250-400 g in two consecutive assays. Ten animals inoculated with saline performed as normal controls in each experiment. Parameters studied were: a) temperature; b) body weight; c) neutralizing antibodies to Junin virus; d) response to viral challenge. Animals gained weight and remained normothermic up to the challenge. Guinea pigs that received Candid #1 from any manufacturer elicited neutralizing antibodies to Junin virus (titles from 40 to 81920) and survived to challenge whilst 8/10 animals died in each control group. Data presented demonstrated that Candid #1 vaccines from USA or Argentine manufacturers were equally safe, immunogenic and protective in guinea pigs.Fil: Ambrosio, Ana M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Saavedra, María del Carmen. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Riera, Laura M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Sottosanti, María J. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina

Neutralization test for lymphocytic choriomeningitis virus for distinguishing between two arenavirus infections in Argentina

Fil: Ambrosio, Ana M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Riera, Laura. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Saavedra, María del Carmen. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Sottosanti, María J. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.The active coexistence of two pathogenic arenaviruses, Junin (JUNV) and lymphocytic choriomeningitis (LCMV), in the same region of Argentina, has been known since the early 70's, and records of clinical and subclinical human infections by one and/or the other agent have been continuously produced for the last 25 years. Anti-LCMV antibody is currently searched only by indirect immunofluorescence, a test that shows cross reactions among a number of arenaviruses yielding, in the cases of LCMV and JUNV consecutive infections, a concomitant seroconversion for both viruses, as an inconclusive diagnostic result. In contrast, neutralization (NT) tests reveal arenavirus antibodies directed to unique epitopes on these virus envelopes, thus allowing to disclose the sequence in the cases of consecutive infections. In this paper, the characteristics of neutralization (NT) test for LCMV in cell cultures are described, as well as its performance in the field diagnosis of LCMV human infections. The native LCMV strain Cba An 13065 was inoculated on L-929 cell (ATCC CCL 1), and procedures were followed to perform a constant virus-variable serum NT test. Final points of sera titrations were expressed as the maximal serum dilution that yielded 75% of pfu inhibition. This NT test was assayed on paired serum samples of 36 patients with confirmed Argentine hemorrhagic fever (AHF) (a disease caused by JUNV), who had had a known previous contact with LCMV through IFI. The use of this one test led to confusing diagnosis of the disease due to concomitant seroconversion for JUNV and LCMV. By using NT test, it was shown that: some of them were possibly not infected by LCMV, and that 30/36 cases (83.3%) had a pre-existing level of LCMV antibody, with titers in the range of 5 to 640, remaining unchanged 60 days after the clinical AHF. This shows that NT antibodies to LCMV are not influenced by the outcome of the immune response to JUNV, thus confirming the efficiency of NT test as identificator among arenaviruses. To assess the performance of this NT test in individuals having only IFI antibodies to LCMV, 126 serum samples obtained through serological surveillance in a rural area of Argentina, were used. It was found that NT had improved coincidence with IFI as IFI titers increased. Interpretations were based on the pan-arenavirus antibody response obtained by using IFI as the only test. Results presented herein prove that the described NT test is a valuable tool for the detection of LCMV infections, particularly when a previous infection with LCMV has to be demonstrated during the acute phase of Argentine hemorrhagic fever

Neutralization test for lymphocytic choriomeningitis virus for distinguishing between two arenavirus infections in Argentina

Fil: Ambrosio, Ana M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Riera, Laura. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Saavedra, María del Carmen. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Sottosanti, María J. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.The active coexistence of two pathogenic arenaviruses, Junin (JUNV) and lymphocytic choriomeningitis (LCMV), in the same region of Argentina, has been known since the early 70's, and records of clinical and subclinical human infections by one and/or the other agent have been continuously produced for the last 25 years. Anti-LCMV antibody is currently searched only by indirect immunofluorescence, a test that shows cross reactions among a number of arenaviruses yielding, in the cases of LCMV and JUNV consecutive infections, a concomitant seroconversion for both viruses, as an inconclusive diagnostic result. In contrast, neutralization (NT) tests reveal arenavirus antibodies directed to unique epitopes on these virus envelopes, thus allowing to disclose the sequence in the cases of consecutive infections. In this paper, the characteristics of neutralization (NT) test for LCMV in cell cultures are described, as well as its performance in the field diagnosis of LCMV human infections. The native LCMV strain Cba An 13065 was inoculated on L-929 cell (ATCC CCL 1), and procedures were followed to perform a constant virus-variable serum NT test. Final points of sera titrations were expressed as the maximal serum dilution that yielded 75% of pfu inhibition. This NT test was assayed on paired serum samples of 36 patients with confirmed Argentine hemorrhagic fever (AHF) (a disease caused by JUNV), who had had a known previous contact with LCMV through IFI. The use of this one test led to confusing diagnosis of the disease due to concomitant seroconversion for JUNV and LCMV. By using NT test, it was shown that: some of them were possibly not infected by LCMV, and that 30/36 cases (83.3%) had a pre-existing level of LCMV antibody, with titers in the range of 5 to 640, remaining unchanged 60 days after the clinical AHF. This shows that NT antibodies to LCMV are not influenced by the outcome of the immune response to JUNV, thus confirming the efficiency of NT test as identificator among arenaviruses. To assess the performance of this NT test in individuals having only IFI antibodies to LCMV, 126 serum samples obtained through serological surveillance in a rural area of Argentina, were used. It was found that NT had improved coincidence with IFI as IFI titers increased. Interpretations were based on the pan-arenavirus antibody response obtained by using IFI as the only test. Results presented herein prove that the described NT test is a valuable tool for the detection of LCMV infections, particularly when a previous infection with LCMV has to be demonstrated during the acute phase of Argentine hemorrhagic fever

Ensayo preclínico de la vacuna candid #1 producida en Argentina contra la fiebre hemorrágica Argentina

Se comparó en cobayos la seguridad, inmunogenicidad y eficacia protectora de un lote de vacuna Candid #1(C#1) fabricada en Estados Unidos de América (EE.UU.) y distintos lotes de la misma vacuna fabricados en Argentina (Arg). El lote TSI 5-1-92 (EE.UU.) y los lotes Exp Nº 3, 7A y 8A (Arg) fueron inoculados (0.5 ml, IM) en cobayos de 250-400 g. Para cada ensayo diez animales recibieron solución fisiológica y sirvieron como control. Todos fueron desafiados con la cepa patógena P23790 de virus Junin. Se registró: a) temperatura rectal, b) peso corporal, c) presencia de anticuerpos neutralizantes (AcNT) pre y post-vacunación, d) respuesta al desafío. Todos los animales vacunados desarrollaron AcNT anti virus Junin (rango = 40- 81920 y sobrevivieron al desafío. En cada grupo control 8/10 animales murieron (día 23.3 ± 5.4 post-desafío). Los cobayos resultaron idénticamente protegidos de una descarga letal de virus Junin por la vacuna importada y los diferentes lotes de C#1 producidos en Argentina.Preclinical assay of Candid #1 vaccine against Argentine Hemorrhagic Fever made in Argentina. Candid #1 vaccine against Argentine Hemorrhagic Fever produced in USA versus lots of the same vaccine made in Argentina were compared in guinea pigs regarding safety, immunogenicity and protective efficacy against a challenge with pathogenic Junin virus. Lots Nº Exp 3, 7A and 8A of Argentine origin as well as lot TSI 5-1-92 from USA were inoculated in guinea pigs of 250-400 g in two consecutive assays. Ten animals inoculated with saline performed as normal controls in each experiment. Parameters studied were: a) temperature; b) body weight; c) neutralizing antibodies to Junin virus; d) response to viral challenge. Animals gained weight and remained normothermic up to the challenge. Guinea pigs that received Candid #1 from any manufacturer elicited neutralizing antibodies to Junin virus (titles from 40 to 81920) and survived to challenge whilst 8/10 animals died in each control group. Data presented demonstrated that Candid #1 vaccines from USA or Argentine manufacturers were equally safe, immunogenic and protective in guinea pigs.Fil: Ambrosio, Ana M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Saavedra, María del Carmen. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Riera, Laura M. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina.Fil: Sottosanti, María J. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas Dr. Julio Maiztegui; Argentina

Serological study of the lymphochoriomeningitis virus (LCMV) in an inner city of Argentina

Fil: Riera, Laura. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Castillo, Ernesto. Dto. Ciencias Naturales. Facultad de Ciencias Exactas, Físico Químicas y Naturales, Universidad Nacional de Río Cuarto, Córdoba; Argentina.Fil: Del Carmen Saavedra, María. . ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Priotto, José. Dto. Ciencias Naturales. Facultad de Ciencias Exactas, Físico Químicas y Naturales, Universidad Nacional de Río Cuarto, Córdoba; ArgentinaFil: Sottosanti, Josefa. . ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Fil: Polop, Jaime. Dto. Ciencias Naturales. Facultad de Ciencias Exactas, Físico Químicas y Naturales, Universidad Nacional de Río Cuarto, Córdoba; Argentina.Fil: Ambrosio, Ana María. . ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Virales Humanas; Argentina.Lymphocytic choriomeningitis virus (LCMV) is the prototype of the family Arenaviridae and is associated with the natural reservoir, Mus domesticus (Md). It causes meningitis and a flu-like illness characterized by malaise, myalgia, retrorbital headache, and photophobia. This study presents the data obtained in a rodent and human serological study during 6 years (1998-2003) in the city of Rio Cuarto, Argentina. Antibodies anti-LCMV were sought by ELISA in rodents and humans. LCMV was found only in Md species in 9.4% of animals. The results also show some seasonal, no significant variations in the prevalence of the infection. Distribution of positive mice was not modified significantly by trapping sites, sex, or age of the animals. The prevalence of LCMV positive urban residents was found to be consistently low (1-3.6%) along the study period, with overage prevalence of 3.3% and values in males (4.6%) significantly higher than in females (2.6%) (P < 0.05). Seven of 432 pregnant women were found to be LCMV positive, but the absence of LCMV antibodies in the newborns demonstrated that the mothers were infected before pregnancy. This study is the first evidence on endemic LCMV in an Argentine city located outside the endemic area of Argentine hemorrhagic fever (AHF) and described the need to study other areas and increase awareness of this viral infection

Prospective observational cohort study on grading the severity of postoperative complications in global surgery research

Background The Clavien–Dindo classification is perhaps the most widely used approach for reporting postoperative complications in clinical trials. This system classifies complication severity by the treatment provided. However, it is unclear whether the Clavien–Dindo system can be used internationally in studies across differing healthcare systems in high- (HICs) and low- and middle-income countries (LMICs). Methods This was a secondary analysis of the International Surgical Outcomes Study (ISOS), a prospective observational cohort study of elective surgery in adults. Data collection occurred over a 7-day period. Severity of complications was graded using Clavien–Dindo and the simpler ISOS grading (mild, moderate or severe, based on guided investigator judgement). Severity grading was compared using the intraclass correlation coefficient (ICC). Data are presented as frequencies and ICC values (with 95 per cent c.i.). The analysis was stratified by income status of the country, comparing HICs with LMICs. Results A total of 44 814 patients were recruited from 474 hospitals in 27 countries (19 HICs and 8 LMICs). Some 7508 patients (16·8 per cent) experienced at least one postoperative complication, equivalent to 11 664 complications in total. Using the ISOS classification, 5504 of 11 664 complications (47·2 per cent) were graded as mild, 4244 (36·4 per cent) as moderate and 1916 (16·4 per cent) as severe. Using Clavien–Dindo, 6781 of 11 664 complications (58·1 per cent) were graded as I or II, 1740 (14·9 per cent) as III, 2408 (20·6 per cent) as IV and 735 (6·3 per cent) as V. Agreement between classification systems was poor overall (ICC 0·41, 95 per cent c.i. 0·20 to 0·55), and in LMICs (ICC 0·23, 0·05 to 0·38) and HICs (ICC 0·46, 0·25 to 0·59). Conclusion Caution is recommended when using a treatment approach to grade complications in global surgery studies, as this may introduce bias unintentionally

The surgical safety checklist and patient outcomes after surgery: a prospective observational cohort study, systematic review and meta-analysis

© 2017 British Journal of Anaesthesia Background: The surgical safety checklist is widely used to improve the quality of perioperative care. However, clinicians continue to debate the clinical effectiveness of this tool. Methods: Prospective analysis of data from the International Surgical Outcomes Study (ISOS), an international observational study of elective in-patient surgery, accompanied by a systematic review and meta-analysis of published literature. The exposure was surgical safety checklist use. The primary outcome was in-hospital mortality and the secondary outcome was postoperative complications. In the ISOS cohort, a multivariable multi-level generalized linear model was used to test associations. To further contextualise these findings, we included the results from the ISOS cohort in a meta-analysis. Results are reported as odds ratios (OR) with 95% confidence intervals. Results: We included 44 814 patients from 497 hospitals in 27 countries in the ISOS analysis. There were 40 245 (89.8%) patients exposed to the checklist, whilst 7508 (16.8%) sustained ≥1 postoperative complications and 207 (0.5%) died before hospital discharge. Checklist exposure was associated with reduced mortality [odds ratio (OR) 0.49 (0.32–0.77); P\u3c0.01], but no difference in complication rates [OR 1.02 (0.88–1.19); P=0.75]. In a systematic review, we screened 3732 records and identified 11 eligible studies of 453 292 patients including the ISOS cohort. Checklist exposure was associated with both reduced postoperative mortality [OR 0.75 (0.62–0.92); P\u3c0.01; I2=87%] and reduced complication rates [OR 0.73 (0.61–0.88); P\u3c0.01; I2=89%). Conclusions: Patients exposed to a surgical safety checklist experience better postoperative outcomes, but this could simply reflect wider quality of care in hospitals where checklist use is routine

Critical care admission following elective surgery was not associated with survival benefit: prospective analysis of data from 27 countries

This was an investigator initiated study funded by Nestle Health Sciences through an unrestricted research grant, and by a National Institute for Health Research (UK) Professorship held by RP. The study was sponsored by Queen Mary University of London