Browsing by Author "Vial, Pablo A."

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    A 19 Year Analysis of Small Mammals Associated with Human Hantavirus Cases in Chile
    (2019) Torres-Perez, Fernando; Eduardo Palma, R.; Boric-Bargetto, Dusan; Vial, Cecilia; Ferres, Marcela; Vial, Pablo A.; Martinez-Valdebenito, Constanza; Pavletic, Carlos; Parra, Alonso; Marquet, Pablo A.; Mertz, Gregory J.
    Small mammals present in areas where hantavirus cardiopulmonary syndrome (HCPS) cases had occurred in central and southern Chile were captured and analyzed to evaluate the abundance of rodents and seroprevalence rates of antibodies to Andes orthohantavirus (ANDV). Sampling areas ranged from the Coquimbo to Aysen regions (30-45 degrees S approx.) regions. Ninety-two sites in peridomestic and countryside areas were evaluated in 19 years of sampling. An antibody against ANDV was detected by strip immunoassay in 58 of 1847 specimens captured using Sherman traps. Of the eleven species of rodents sampled, Abrothrix olivacea, Oligoryzomys longicaudatus and Abrothrix hirta were the most frequently trapped. O. longicaudatus had the highest seropositivity rate, and by logistic regression analysis, O. longicaudatus of at least 60 g had 80% or higher probability to be seropositive. Sex, age and wounds were significantly related to seropositivity only for O. longicaudatus. Across administrative regions, the highest seropositivity was found in the El Maule region (34.8-36.2 degrees S), and the highest number of HCPS cases was registered in the Aysen region. Our results highlight the importance of long term and geographically extended studies, particularly for highly fluctuating pathogens and their reservoirs, to understand the implications of the dynamics and transmission of zoonotic diseases in human populations.
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    A non-randomized multicentre trial of human immune plasma for treatment of hantavirus cardiopulmonary syndrome caused by Andes virus
    (2015) Vial, Pablo A.; Valdivieso, Francisca; Calvo, Mario; Rioseco, M. Luisa; Riquelme, Raul; Araneda, Andres; Tomicic, V.; Graf, Jerónimo; Paredes, Laura; Florenzano, Matias
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    Comparison of VSV Pseudovirus and Focus Reduction Neutralization Assays for Measurement of Anti-Andes orthohantavirusNeutralizing Antibodies in Patient Samples
    (2020) Vial, Cecilia; Whitaker, Annalis; Wilhelm, Jan; Ovalle, Jimena; Perez, Ruth; Valdivieso, Francisca; Ferres, Marcela; Martinez-Valdebenito, Constanza; Eisenhauer, Philip; Mertz, Gregory J.; Hooper, Jay W.; Botten, Jason W.; Vial, Pablo A.
    Andes orthohantavirus(ANDV) is the etiologic agent of hantavirus cardiopulmonary syndrome (HCPS), which has a case fatality rate around 35%, with no effective treatment or vaccine available. ANDV neutralizing antibody (NAb) measurements are important for the evaluation of the immune response following infection, vaccination, or passive administration of investigational monoclonal or polyclonal antibodies. The standard assay for NAb measurement is a focus reduction neutralization test (FRNT) featuring live ANDV and must be completed under biosafety level (BSL)-3 conditions. In this study, we compared neutralization assays featuring infectious ANDV or vesicular stomatitis virus (VSV) pseudovirions decorated with ANDV glycoproteins for their ability to measure anti-ANDV NAbs from patient samples. Our studies demonstrate that VSV pseudovirions effectively measure NAb from clinical samples and have greater sensitivity compared to FRNT with live ANDV. Importantly, the pseudovirus assay requires less labor and sample materials and can be conducted at BSL-2.
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    High-dose intravenous methylprednisolone for hantavirus cardiopulmonary syndrome in Chile : a double-blind, randomized controlled clinical trial
    (2013) Vial, Pablo A.; Valdivieso, Francisca; Ferrés Garrido, Marcela Viviana; Riquelme, Raúl; Rioseco, M. Luisa; Calvo, Mario; Castillo, Constanza; Díaz, Ricardo; Scholz, Luis; Cuiza, Analia
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    Incubation period of hantavirus cardiopulmonary syndrome
    (CENTERS DISEASE CONTROL & PREVENTION, 2006) Vial, Pablo A.; Valdivieso, Francisca; Mertz, Gregory; Castillo, Constanza; Belmar, Edith; Delgado, Iris; Tapia, Mauricio; Ferres, Marcela
    The potential incubation period from exposure to onset of symptoms was 7-39 days (median 18 days) in 20 patients with a defined period of exposure to Andes virus in a high-risk area. This period was 14-32 days (median 18 days) in 11 patients with exposure for <= 48 hours.
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    Platelet Count in Patients with Mild Disease at Admission is Associated with Progression to Severe Hantavirus Cardiopulmonary Syndrome
    (2019) Lopez, Rene; Vial, Cecilia; Graf, Jeronimo; Calvo, Mario; Ferres, Marcela; Mertz, Gregory; Cuiza, Analia; Agueero, Begonia; Aguilera, Dante; Araya, Diego; Pailamilla, Ignacia; Paratori, Flavia; Torres-Torres, Victor; Vial, Pablo A.; Abarca, Juan; Miguel Noriega, Luis; Valdivieso, Francisca; Delgado, Iris; Martinez, Constanza; Carlos Chamorro, Juan; Hernandez, Jury; Pino, Marcelo; Vega, Ivonne; Otarola, Irisol; Ortega, Carlos; Daube, Elizabeth; Castillo, Constanza; Mardones, Jovita; Sanhueza, Ligia; Inostroza, Jaime; Donoso, Solange; Navarrete, Maritza; Araneda, Andres; Aguilera, Teresa; Osorio, Carola; Yobanolo, Veronica; Scholz, Luis; Riquelme, Raul; Riquelme, Mauricio; Munoz, Miriam
    Background: Hantavirus cardiopulmonary syndrome (HCPS) has a mortality up to 35-40% and its treatment is mainly supportive. A variable to predict progression from mild to severe disease is unavailable. This study was performed in patients with documented infection by Andes orthohantavirus, and the aim was to find a simple variable to predict progression to moderate/severe HCPS in patients with mild disease at admission. Methods: We performed a retrospective analysis of 175 patients between 2001 and 2018. Patients were categorized into mild, moderate, and severe disease according to organ failure and advanced support need at hospital admission (e.g., mechanical ventilation, vasopressors). Progression to moderate/severe disease was defined accordingly. Clinical and laboratory variables associated with progression were explored. Results: Forty patients with mild disease were identified; 14 of them progressed to moderate/severe disease. Only platelet count was different between those who progressed versus those that did not (37 (34-58) vs. 83 (64-177) K/mm(3), p < 0.001). A ROC curve analysis showed an AUC = 0.889 (0.78-1.0) p < 0.001, with a platelet count greater than 115K /mm(3) ruling out progression to moderate/severe disease. Conclusions: In patients with mild disease at presentation, platelet count could help to define priority of evacuation to tertiary care centers.
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    Post-COVID-19 condition: a sex-based analysis of clinical and laboratory trends
    (2024) Delfino, Carlos; Poli, M. Cecilia; Vial, Cecilia; Vial, Pablo A.; Martinez, Gonzalo; Riviotta, Amy; Arbat, Catalina; Mac-Guire, Nicole; Hoppe, Josefina; Carvajal, Cristobal; Venturelli, Paula Munoz
    Background and aim Post-COVID-19 condition (PCC) encompasses long-lasting symptoms in individuals with COVID-19 and is estimated to affect between 31-67% of patients, with women being more commonly affected. No definitive biomarkers have emerged in the acute stage that can help predict the onset of PCC, therefore we aimed at describing sex-disaggregated data of PCC patients from a local cohort and explore potential acute predictors of PCC and neurologic PCC. Methods A local cohort of consecutive patients admitted with COVID-19 diagnosis between June 2020 and July 2021 were registered, and clinical and laboratory data were recorded. Only those <65 years, discharged alive and followed up at 6 and 12 months after admission were considered in these analyses. Multivariable logistic regression analysis was performed to explore variables associated with PCC (STATA v 18.0). Results From 130 patients in the cohort, 104 were contacted: 30% were women, median age of 42 years. At 6 months, 71 (68%) reported PCC symptoms. Women exhibited a higher prevalence of any PCC symptom (87 vs. 60%, p = 0.007), lower ferritin (p = 0.001) and procalcitonin (p = 0.021) and higher TNF levels (p = 0.042) in the acute phase compared to men. Being women was independently associated to 7.60 (95% CI 1.27-45.18, p = 0.026) higher risk for PCC. Moreover, women had lower return to normal activities 6 and 12 months. Conclusion Our findings highlight the lasting impact of COVID-19, particularly in young women, emphasising the need for tailored post-COVID care. The lower ferritin levels in women are an intriguing observation, warranting further research. The study argues for comprehensive strategies that address sex-specific challenges in recovery from COVID-19.
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    PREDICTING HANTAVIRUS RISK IN CHILE
    (AMER SOC TROP MED & HYGIENE, 2008) Glass, Gregory E.; Marquet Iturriaga Pablo Angel; Palma Troncoso Rodrigo Eduardo; Barria, Ivan; Yates, Terry L.; Vial, Pablo A.; Ferres Garrido, Marcela Viviana; Mertz, Gregory J.
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    Proteinuria in Hantavirus Cardiopulmonary Syndrome: A Frequent Finding Linked To Mortality
    (2021) Lopez, Rene; Espinoza, Mauricio; Graf, Jeronimo; Mertz, Gregory; Ferres, Marcela; Calvo, Mario; Vial, Cecilia; Vial, Pablo A.
    Objectives: To determine the relative frequency and prognosis value of proteinuria in hantavirus cardiopulmonary syndrome (HCPS) due to Andes virus. Methods: This observational analytical study prospectively obtained data from patients admitted to 12 health centers in nine Chilean cities between 2001 and 2018. Only patients with confirmed Andes virus HCPS and laboratory characterization that included qualitative proteinuria determination at admission were considered. Results: The database involved 175 patients, 95 of them had a measurement of urine protein at the time of hospital admission. They were mainly male (71%) and the median age was 35 [22-47] years. Median duration of the febrile prodromal time was 5 [4-7] days. Hospital length of stay and hospital mortality rate were 10 [7-14] days and 21.1%, respectively. Seventy-three patients (77%) were identified with proteinuria at admission, which was associated with increased mortality rate (26% versus 5%, p = 0.036) and the relative risk was 1.3 [1.1-1.6], p = 0.002. Conclusions: Proteinuria is a frequent finding in patients with HCPS, which is associated with a higher mortality rate. (c) 2021 The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )
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    SARS-CoV-2 Antibody Prevalence among 85,529 Healthcare Workers following the First Wave of COVID-19 in Chile
    (2021) Zuñiga, Marcela; O'Ryan, Miguel; Bertoglia, María Paz; Bravo Valenzuela, Paulina Fabiola; Lagomarcino, Anne J.; Muñoz, Sergio; Peña Alonso, Alfredo; Rodriguez, María Andrea; Vial, Pablo A.
    Background: Healthcare workers (HCWs) are at increased risk for SARS-CoV-2 infection, however not all face the same risk. We aimed to determine antibody prevalence and risk factors associated with seropositivity in the Chilean HCW community. Methods: This was a nationwide, cross-sectional study consisting of a questionnaire and COVID-19 antibody testing. All HCWs in the Chilean public health care system were invited to participate three to four months following the peak of the country's first wave. Findings: Overall SARS-Cov-2 blood antibody positivity by fingerstick or venipuncture in 85 529 HCWs was 7 · 2%, ranging from 1 · 6% to 12 · 4% between regions. SARS-Cov-2 positive PCR results were self-reported in 8 330 individuals (9 · 7%) of which 47% were seropositive. Overall 10 863 (12 · 7%) either reported prior PCR positive results and/or were seropositive. Several factors were independently associated with higher IRR for seropositivity, including working in hospital (IRR 1·484), medicine/surgery w ards (IRR 1·383), emergency room (IRR 1·266), and night shifts (IRR 1·616), as were history of contact with a confirmed case (IRR 1·462), and use of public transport (IRR 1·367). These variables remained significant when including self-reported PCR positive cases in the model. Interpretation: HCWs in the hospital were at highest risk for COVID-19, especially if working in medicine/surgery wards or emergency rooms, in night shifts, older age, exposed to confirmed cases and/or using public transport. Antibody results using lateral flow likely underestimated true infection rates by nearly 40-50%. Nevertheless, risk factors were sustained when adjusting for self-reported PCR positive cases.