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Thymectomy for non-thymomatous myasthenia gravis
(2013)
Gabriel Cea
;
Michael Benatar
;
Renato J Verdugo
;
Rodrigo A Salinas
2Scopus© Citations 45
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Evaluation of Eight Serological Tests for Diagnosis of Imported Schistosomiasis
(2012)
Hans-Friedemann Kinkel
;
Sabine Dittrich
;
Britta Bäumer
;
WEITZEL, THOMAS
<jats:title>ABSTRACT</jats:title> <jats:p> The diagnosis of schistosomiasis in individuals from countries where the disease is not endemic is challenging, and few data are available on the accuracy of serological diagnosis in those patients. We evaluated the performance of eight serological assays, including four commercial kits, in the diagnosis of imported schistosomiasis in individuals from areas where the disease is not endemic, including six enzyme-linked immunosorbent assays using three different antigens, an indirect hemagglutination assay, and an indirect immunofluorescent-antibody test. To analyze the assays, we used a total of 141 serum samples, with 121 derived from patients with various parasitic infections (among which were 37 cases of schistosomiasis) and 20 taken from healthy volunteers. The sensitivity values for detection of schistosomiasis cases ranged from 41% to 78% and were higher for <jats:named-content content-type="genus-species">Schistosoma mansoni</jats:named-content> than for <jats:named-content content-type="genus-species">S. haematobium</jats:named-content> infections. Specificity values ranged from 76% to 100%; false-positive results were most frequent for samples from patients with cestode infections. By combining two or more tests, sensitivity improved markedly and specificity decreased only moderately. Serological tests are useful instruments for diagnosing imported schistosomiasis in countries where the disease is not endemic, but due to limitations in test sensitivities, we recommend the use of two or more assays in parallel. </jats:p>
Scopus© Citations 91
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Seroprevalence of Natural and Acquired Immunity against the SARS-CoV-2 Virus in a Population Cohort from Two Chilean Cities, 2020–2022
(2023)
Loreto Núñez-Franz
;
Muriel Ramírez-Santana
;
RUBILAR RAMIREZ, PAOLA
;
Macarena Said
;
VIAL COX, MARIA CECILIA
<jats:p>Background: Chile has achieved the highest coverage for vaccines against the SARS-CoV-2 virus worldwide. Objective: To assess the progression of immunity (natural and acquired by vaccine) in a cohort from two Chilean cities. Methods: Individuals (n = 386) who participated in three phases of population-based serial prevalence studies were included (2020–2021 and 2022). Presence of SARS-CoV-2 antibodies was measured in serum. Data including time of vaccination and type of vaccine received were analysed with descriptive statistics. Results: Seroprevalence was 3.6% in the first round and increased to 96.9% in the second and 98.7% in the third. In the third round, 75% of individuals who had received the basal full scheme were seropositive at 180 days or more since their last dose; 98% of individuals who received one booster dose were seropositive at 180 days or more, and 100% participants who received two boosters were seropositive, regardless of time since their last dose. Participants receiving mRNA vaccines had higher seroprevalence rates over time. Conclusions: The high vaccination coverage in Chile enabled the population to maintain high levels of antibodies. Vaccination boosters are essential to maintain immunity over time, which also depends on the type of vaccine administered.</jats:p>
1Scopus© Citations 12
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Serological study of CoronaVac vaccine and booster doses in Chile: immunogenicity and persistence of anti-SARS-CoV-2 spike antibodies
(2022)
Leonardo Vargas
;
Nicolás Valdivieso
;
Fabián Tempio
;
Valeska Simon
;
Daniela Sauma
<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background</jats:title> <jats:p>Chile was severely affected by COVID19 outbreaks but was also one of the first countries to start a nationwide program to vaccinate against the disease. Furthermore, Chile became one of the fastest countries to inoculate a high percentage of the target population and implemented homologous and heterologous booster schemes in late 2021 to prevent potential immunological waning. The aim of this study is to compare the immunogenicity and time course of the humoral response elicited by the CoronaVac vaccine in combination with homologous versus heterologous boosters.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>We compared the immunogenicity of two doses of CoronaVac and BNT162b2 vaccines and one homologous or heterologous booster through an ELISA assay directed against the ancestral spike protein of SARS-CoV-2. Sera were collected from individuals during the vaccination schedule and throughout the implementation of homologous and heterologous booster programs in Chile.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>Our findings demonstrate that a two-dose vaccination scheme with CoronaVac induces lower levels of anti-SARS-CoV-2 spike antibodies than BNT162b2 in a broad age range (median age 42 years; interquartile range (IQR) 27-61). Furthermore, antibody production declines with time in individuals vaccinated with CoronaVac and less noticeably, with BNT162b2. Analysis of booster schemes revealed that individuals vaccinated with two doses of CoronaVac generate immunological memory against the SARS-CoV-2 ancestral strain, which can be re-activated with homologous or heterologous (BNT162b2 and ChAdOx1) boosters. Nevertheless, the magnitude of the antibody response with the heterologous booster regime was considerably higher (induction fold BNT162b2: 11.2x; ChAdoX1; 12.4x; CoronaVac: 6.0x) than the responses induced by the homologous scheme. Both homologous and heterologous boosters induced persistent humoral responses (median 122 days, IQR (108-133)), although heterologous boosters remained superior in activating a humoral response after 100 days.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Two doses of CoronaVac induces antibody titers against the SARS-CoV-2 ancestral strain which are lower in magnitude than those induced by the BNT162b2 vaccine. However, the response induced by CoronaVac can be greatly potentiated with a heterologous booster scheme with BNT162b2 or ChAdOx1 vaccines. Furthermore, the heterologous and homologous booster regimes induce a durable antibody response which does not show signs of decay 3 months after the booster dose.</jats:p> </jats:sec>
Scopus© Citations 14 1
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Miopatías inflamatorias idiopáticas: una mirada actualizada al diagnóstico y el manejo
(2019)
IGNACIO JAVIER ACOSTA CARRASCO
;
José Manuel Matamala
;
Paula Jara
;
Francisca Pino
;
Alejandra Gallardo
Scopus© Citations 12 2
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Person-to-Person Household and Nosocomial Transmission of Andes Hantavirus, Southern Chile, 2011
(2014)
Constanza Martinez-Valdebenito
;
Mario Calvo
;
VIAL COX, MARIA CECILIA
;
Rita Mansilla
;
Claudia Marco
22Scopus© Citations 90
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Renal involvement in antineutrophil cytoplasmic antibodies (ANCA) associated vasculitides. Recommendations of the Chilean Societies of Nephrology and Rheumatology
(2018)
Verónica Aguirre
;
Miriam Alvo
;
Leopoldo Ardiles
;
Alberto Fierro
;
Annelise Goecke
9 1

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