COI vs Ct: comparing automated antigen tests cut-off index (COI) to PCR cycle threshold (Ct).

INTRODUCTION: The objective of this study was to compare the numeric cut-off index (COI) of automated antigen tests with the cycle-threshold (Ct) value. MATERIALS AND METHODS: COI values of all samples processed with the Elecsys® SARS-CoV-2 Antigen (Roche, Switzerland) from January to February 2022 were retrieved and the positive were compared to RdRP Cts of Allplex Variants I (Seegene, Korea). COI between 0.6 and 1 were considered indeterminate and overproved by RT-PCR. RESULTS: From 13,937 samples 7944(57%) were positive and 189(1.35%) indeterminate. There was a strong correlation between Cts and COI values at the positive samples, but that was not the case for indeterminates. CONCLUSIONS: COI values of the positive samples (COI >1) are comparable to Ct values and may therefore be used as proxy viral loads, however this is not the case for indeterminate samples.

Repurposing Positive SARS-CoV-2 Antigen Test Devices for Variant Tracking.

From the very beginning of the SARS-CoV-2 pandemic, one of the very few common opinions was that to control the expansion of the virus as many as the possible test had to be done. Antigen tests, being affordable and easy and fast to use, represented a great opportunity to expand the testing capacities of many healthcare systems. However, in 2021 with the appearance of the new SARS-CoV-2 variants, variant tracking strategies had to be implemented, which often included needing a second test to determine the variant of the patients diagnosed with antigen tests or not taking these samples into consideration at all. Therefore, we proposed recovering the positive antigen test devices to include them in our routine variant tracking strategy. The recovered positive antigen test devices obtained from 1st April 2021 to 15the January 2022 were analysed following the variant tracking protocol in force. The results obtained were compared to the positive samples detected by RT-PCR which were processed for variant tracking during the same period. 21,304 samples were processed, 6297 from the recovered positive antigen devices and 15,007 from the standard nasopharyngeal swabs. Only 773 (3.63%) samples were no conclusive, 104 (1.65%) from the recovered antigen devices and 669 (4.46%) from the RT-PCR positive group. This difference was statistically significant (p < 0.01). Taking this into account the proposed method is suitable and very recommendable, as it is an important measure to have a better and immediate picture of the circulating variants in every community.

Characteristics of genital herpes in Bilbao (Northern Spain): 12-year retrospective study / Características del herpes genital en Bilbao (Norte de España): estudio retrospectivo de 12 años

Introducción: El virus herpes simple tipo 2 (VHS-2) es la causa más frecuente de herpes genital (HG), pero la infección genital por el virus herpes simple tipo 1 (VHS-1) está en aumento. El objetivo del estudio fue analizar las características epidemiológicas de pacientes con HG. Métodos: Estudio retrospectivo desde enero del 2004 hasta diciembre del 2015 de pacientes con HG atendidos en 2 consultas de enfermedades de transmisión sexual (ETS) en la Organización Sanitaria Integrada Bilbao-Basurto, en el norte de España. Se revisaron y analizaron los datos de interés de los pacientes. Resultados: Mil tres pacientes (524 hombres y 479 mujeres) fueron incluidos. El 74% tenía infección por VHS-2. El VHS-1 aumentó durante el periodo estudiado, significativamente en hombres (28% en 2004-2007 vs. 50% en 2012-2015). El VHS-1 fue mayor en mujeres en comparación con hombres (56% vs. 44%). La infección primaria fue más frecuente en los infectados con VHS-1 comparado con VHS-2 (79% vs. 21%). En pacientes con VHS-1, la infección primaria fue superior en hombres (86%) y en menores de 30 años. El 63% de las infecciones por VHS-2 fueron recurrencias. En el análisis multivariante, la edad, el origen extranjero, la recurrencia, el contacto previo con HG de la pareja sexual, la infección previa por Neisseria gonorrhoeae y la prostitución se asociaron con mayor riesgo de infección por VHS-2. Conclusiones:El VHS-2 fue la causa principal del HG, pero la proporción de VHS-1 aumentó. El antecedente de ETS y las conductas sexuales de riesgo fueron predominantes en los pacientes con HG por VHS-2.(AU)

Background: Herpes simplex virus type 2 (HSV-2) is the most common cause of genital herpes (GH), but genital infection by herpes simplex virus type 1 (HSV-1) is increasing. The aim of this study was to analyze and compare epidemiological characteristics of patients with GH. Methods:Retrospective study conducted from January 2004 to December 2015 in patients with GH attended at two Sexually Transmitted Diseases (STDs) medical consultation of Bilbao-Basurto Integrated Health Organisation in Northern Spain. Patient's medical history was reviewed and data of interest was analyzed. Results: One thousand three patients (524 male and 479 female) were reviewed. HSV-2 was detected in 74%. The proportion of HSV-1 increased during the study period, significantly in men (28% in 2004–2007 vs. 50% in 2012–2015). More female than male had HSV-1 infection (56% vs. 44%). The proportion of primary infection was higher among HSV-1 compared to HSV-2 (79% vs. 21%). Among the patients with HSV-1, primary infection was higher among men (86%) and in younger than 30 years. Recurrent GH was higher among HSV-2 infections (63%). In a multivariate model older age, geographic origin outside Spain, recurrent infection, prior contact with a partner's genital herpetic lesions, previous N. gonorrhoeae infection and prostitution were significantly associated with HSV-2 infection. Conclusions: HSV-2 was the most common causative agent of GH, but the proportion of HSV-1 increased. Overall, antecedent of STD and sexual risk behaviors were more frequent in patients with genital HSV-2 infection.(AU)

Characteristics of genital herpes in Bilbao (Northern Spain): 12-year retrospective study.

BACKGROUND: Herpes simplex virus type 2 (HSV-2) is the most common cause of genital herpes (GH), but genital infection by herpes simplex virus type 1 (HSV-1) is increasing. The aim of this study was to analyze and compare epidemiological characteristics of patients with GH. METHODS: Retrospective study conducted from January 2004 to December 2015 in patients with GH attended at two Sexually Transmitted Diseases (STDs) medical consultation of Bilbao-Basurto Integrated Health Organisation in Northern Spain. Patient's medical history was reviewed and data of interest was analyzed. RESULTS: One thousand three patients (524 male and 479 female) were reviewed. HSV-2 was detected in 74%. The proportion of HSV-1 increased during the study period, significantly in men (28% in 2004-2007 vs. 50% in 2012-2015). More female than male had HSV-1 infection (56% vs. 44%). The proportion of primary infection was higher among HSV-1 compared to HSV-2 (79% vs. 21%). Among the patients with HSV-1, primary infection was higher among men (86%) and in younger than 30 years. Recurrent GH was higher among HSV-2 infections (63%). In a multivariate model older age, geographic origin outside Spain, recurrent infection, prior contact with a partner's genital herpetic lesions, previous N. gonorrhoeae infection and prostitution were significantly associated with HSV-2 infection. CONCLUSIONS: HSV-2 was the most common causative agent of GH, but the proportion of HSV-1 increased. Overall, antecedent of STD and sexual risk behaviors were more frequent in patients with genital HSV-2 infection.