Massive testing in the Galapagos Islands and low positivity rate to control SARS-CoV-2 spread during the first semester of the COVID-19 pandemic: a story of success for Ecuador and South America.

INTRODUCTION: During the first months of the COVID-19 pandemic in Latin America, countries like Ecuador, Peru and Colombia experienced chaotic scenarios with public health systems collapsing and lack of testing capacity to control the spread of the virus. In main cities like Guayaquil in Ecuador, dramatic situations such as corpses in the streets were internationally broadcasted. METHODS: While the COVID-19 pandemic was devastating South America, SARS-CoV-2 transmission was successfully managed in the Galapagos Islands due to the implementation of a massive screening strategy including hospitalized and community-dwelling populations, and travel restrictions facilitated by its geographical location (972 km from the Ecuadorian continental territory). Floreana Island was one of the few locations in the world that remained COVID-19 free during 2020. RESULTS: In this study, we retrospectively analyzed the data related to SARS-CoV-2 massive testing campaigns from April to September 2020 in the Galapagos Islands, and found this territory to have the lowest positivity rate in South America (4.8-6.7%) and the highest testing ratio among Ecuadorian provinces (9.87% of the population, which is 2480 out of 25 124 inhabitants) during the first wave of the COVID-19 pandemic. CONCLUSION: This story of success was possible because of the interinstitutional collaboration between the regional government of Galapagos Islands (Consejo de Gobierno), the local authorities (Gobiernos Autonomos Descentralizados de Santa Cruz, San Cristobal and Isabela), the regional authorities from Ecuadorian Ministry of Health, the Agencia de Regulación y Control de la Bioseguridad y Cuarentena para Galápagos and Universidad de Las Américas.

A recent distemper virus outbreak in the growing canine populations of Galapagos Islands: a persistent threat for the endangered Galapagos Sea Lion.

Canine Distemper Virus (CDV) is a highly contagious virus that can cross mammalian species barriers and has widespread impacts on both domestic animals and wildlife populations. This study describes a recent outbreak of CDV in the Galapagos Islands in 2019. A total number of 125 dogs with clinical signs compatible with CDV were included in this study. Nasal swabs were taken and analyzed by RT-qPCR for the detection of CDV, resulting in a positivity rate of 74.4% (IC95%, 66-81%). Among the CDV positive dogs, 82.2% presented with respiratory signs, 48.8% neurological signs, and 28.9% gastrointestinal signs. CDV has been previously reported in the domestic canine population of the Galapagos Islands in 2001 and 2004. The current study shows how CDV is still a threat for the endemic and endangered Galapagos sea lion, despite recent policies for dog population control and CDV vaccination.

High sensitivity-low cost detection of SARS-CoV-2 by two steps end point RT-PCR with agarose gel electrophoresis visualization.

More than one year since Coronavirus disease 2019 (COVID-19) pandemic outbreak, the gold standard technique for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection is still the RT-qPCR. This is a limitation to increase testing capacities, particularly at developing countries, as expensive reagents and equipment are required. We developed a two steps end point RT-PCR reaction with SARS-CoV-2 Nucleocapsid (N) gene and Ribonuclease P (RNase P) specific primers where viral amplicons were verified by agarose gel electrophoresis. We carried out a clinical performance and analytical sensitivity evaluation for this two-steps end point RT-PCR method with 242 nasopharyngeal samples using the CDC RT-qPCR protocol as a gold standard technique. With a specificity of 95.8%, a sensitivity of 95.1%, and a limit of detection of 20 viral RNA copies/uL, this two steps end point RT-PCR assay is an affordable and reliable method for SARS-CoV-2 detection. This protocol would allow to extend COVID-19 diagnosis to basic molecular biology laboratories with a potential positive impact in surveillance programs at developing countries.

Analytical and clinical comparison of Viasure (CerTest Biotec) and 2019-nCoV CDC (IDT) RT-qPCR kits for SARS-CoV2 diagnosis.

BACKGROUND: Several RT-qPCR kits are available for SARS-CoV-2 diagnosis, some of them with Emergency Use Authorization (EUA) by FDA, but most of them lacking of proper evaluation studies due to covid19 emergency. OBJECTIVE: We evaluated Viasure RT-qPCR kit (CerTest Biotec, Spain) for SARS-CoV-2 diagnosis using FDA EUA 2019-nCoV CDC kit (IDT, USA) as a gold standard. RESULTS: Although we found the lack of RNA quality control probe as the main limitation for the Viasure kit, the sensitivity was 91.9% and the specificity was 100%. The limit of detection (LOD) was 2000 copies/mL and 1000 copies/mL for Viasure and IDT kits, respectively. CONCLUSIONS: Viasure RT-qPCR kit is a reliable tool for SARS-CoV-2 diagnosis but improvement of an alternative RT-qPCR reaction for RNA extraction quality control as RNaseP is recommended.

Corrigendum to: "One health" inspired SARS-CoV-2 surveillance: The Galapagos Islands experience [One Health 11 (2020) 100185].

[This corrects the article DOI: 10.1016/j.onehlt.2020.100185.].

"Sample pooling of RNA extracts to speed up SARS-CoV-2 diagnosis using CDC FDA EUA RT-qPCR kit".

BACKGROUND: The CDC protocol for SARS-CoV2 RT-PCR diagnosis (2019-nCoV CDC kit) is considered a gold standard worldwide; based on three different FAM probes (N1 and N2 for viral detection; RP for RNA extraction quality control), three reactions per sample are needed for SARS-CoV-2 diagnosis. RESULTS: We herein describe a sample pooling protocol: pooling 3 RNA extractions into a single PCR reaction; we tested this protocol with 114 specimens grouped in 38 pools and found no significant differences for N1 and N2 Ct values between pool and single sample PCR reaction. CONCLUSION: This pool of three protocol has a sensitivity of 100 % compared to the standard single sample protocol. For a typical 96-well plate, this pool assay allows 96 samples processing, speeding up diagnosis and reducing cost while maintaining clinical performance, particularly useful for SARS-CoV-2 diagnosis at developing countries.

Cotton-Tipped Plastic Swabs for SARS-CoV-2 RT-qPCR Diagnosis to Prevent Supply Shortages.

CDC and WHO guidelines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis only recommend synthetic fiber swabs for nasopharyngeal (NP) sampling. We show that cotton-tipped plastic swabs do not inhibit PCR and have equivalent performance to rayon swabs. Cotton-tipped plastic swabs are massively produced worldwide and would prevent swab supply shortages under the current high SARS-CoV-2 testing demands, particularly in developing countries.

Canine vector-borne disease in domestic dogs on Isla Santa Cruz, Galápagos.

Vector-borne diseases result in significant morbidity and mortality in domestic dogs in tropical and subtropical regions and also pose a potential threat to wildlife species and humans. Ehrlichia canis, the causative agent of canine monocytic ehrlichiosis (CME), has a high reported seroprevalence in dogs on Santa Cruz in the Galápagos Islands, Ecuador. Veterinary diagnostic and treatment resources are often scarce and clinical follow-up is lacking in the Galápagos. This study evaluated 58 dogs presenting to the Darwin Animal Doctors clinic in the city of Puerto Ayora on Santa Cruz Island during August of 2018. The seroprevalence of E. canis/Ehrlichia ewingii (48.3%), Anaplasma phagocytophilum/Anaplasma platys (12.1%), and Borrelia burgdorferi (0%), as well as the proportion of dogs actively infected with E. canis (12.1%) and E. ewingii (0%), are reported. Active infection was defined as the identification of antigen by PCR. Dogs with a packed cell volume (PCV) ≤ 30% had a 10-fold risk of active infection with E. canis compared to dogs with a PCV ≥ 31% (p = .0124). A PCV cutoff of 30% may be a useful screening tool for active E. canis infection in regions with high Ehrlichia seroprevalence, in the absence of other apparent causes of anemia. Dirofilaria immitis antigen was present in 6.9% of examined dogs, with the highest prevalence in the barrio Las Ninfas. PCR and Sanger sequencing were used to provide the first molecular identification of D. immitis in the Galápagos. This study updates the seropositivity and prevalence data of these canine vector-borne pathogens and highlights the need for continued surveillance in the region.

Evaluation of nCoV-QS (MiCo BioMed) for RT-qPCR detection of SARS-CoV-2 from nasopharyngeal samples using CDC FDA EUA qPCR kit as a gold standard: An example of the need of validation studies.

BACKGROUND: Several qPCR kits are available for SARS-CoV-2 diagnosis, mostly lacking of evaluation due to covid19 emergency. OBJECTIVE: We evaluated nCoV-QS (MiCo BioMed) kit using CDC kit as gold standard. RESULTS: We found limitations for nCoV-QS: 1) lower sensitivity 2) lack of RNA quality control probe. CONCLUSIONS: Validation studies should be implemented for any SARS-CoV-2 RT-qPCR commercial kit to prevent unreliable diagnosis.

"One health" inspired SARS-CoV-2 surveillance: The Galapagos Islands experience.

The COVID-19 pandemic has spread worldwide since the outbreak in Wuhan (China) in December 2019, currently infecting over 25 million people and causing more than 800.000 deaths. In Ecuador, up to the 30th of August 2020, overall 113.648 confirmed cases and 6.555 deaths have been declared. Besides overloading of hospital, capacity for molecular diagnosis of SARS-CoV-2 by the Ministry of Public Health was quickly overwhelmed. In this context, emergency authorization for SARS-CoV-2 RT-qPCR diagnosis was granted to other institutions, like the "Agencia de Regulación y Control para la Bioseguridad y Cuarentena de Galápagos" (ABG), that implemented "LabGal" with support of One Health Research Group from "Universidad de Las Américas" (UDLA). The previous experience of ABG and the One Health Research Group in conducting massive surveillance of zoonotic diseases on livestock was crucial to the success on the control of COVID-19 outbreak at Galapagos Islands by the end of May 2020, when Latin American countries were leading the spread of the pandemic.

Left ventricular mass regression after aortic valve replacement with the new Mitroflow 12A pericardial bioprosthesis.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the durability of the new Mitroflow 12A pericardial bioprosthesis and to assess ventricular mass regression after aortic valve replacement (AVR) in patients with small valves. METHODS: A total of 326 Mitroflow 12A pericardial bioprostheses was implanted without any other associated valve procedure. The mean patient age was 73.5 +/- 6.1 years; 252 patients (78.0%) were in NYHA class III/IV. Small valves (19 and 21 mm) were implanted in 212 patients (65.6%). The total follow up period was 837.1 patient-years (pt-yr). A subset of 61 patients with preoperative stenosis was selected and submitted to conventional echo-Doppler assessment at a mean period of 11.1 months after surgery. RESULTS: Hospital mortality was 8.6%. At eight years of follow up, survival was 57.1%. Freedom from structural valve deterioration (SVD) was 86.5% per pt-yr. Mean gradients were significantly reduced postoperatively for each valve size (to 18 +/- 8 mmHg for 19-mm valves and 12 +/- 4 mmHg for 25-mm valves). The effective orifice area (EOA) was also increased significantly for all valve sizes (to 1.1 +/- 0.1 cm2 for 19-mm valves and 1.8 +/- 0.2 cm2 for 25-mm valves). The left ventricular mass index (LVMI) decreased significantly, from 177 +/- 29 to 136 +/- 22 g/m2 for the 19-mm valve, and from 200 +/- 42 to 132 +/- 22 g/m2 for the 25-mm valve. The EOA index (EOAI) showed mismatch for the 19- and 21-mm valves (0.74 and 0.82 cm2/m2, respectively). The diagrammatic calculation between LVMI and relative wall thickness after surgery showed that 29.7% of patients achieved a normal pattern of remodeling (including 19- and 21-mm valves), despite various degrees of mismatch. CONCLUSION: The new Mitroflow 12A pericardial bioprosthesis showed an absence of mechanical failure after an eight-year follow up, with a satisfactory rate of SVD. Significant reductions in LVMI and improved ventricular geometry were observed, despite the small valve sizes implanted.

Minimally invasive surgical implantation of left ventricular epicardial leads for ventricular resynchronization using video-assisted thoracoscopy.

BACKGROUND AND OBJECTIVES: Cardiac resynchronization via left ventricular or biventricular pacing is an option for selected patients with ventricular systolic dysfunction and widened QRS complex. Stimulation through a coronary vein is the technique of choice for left ventricular pacing, but this approach results in a failure rate of approximately 8%. We describe our initial experience with minimally invasive surgical implantation of left ventricular epicardial leads using video-assisted thoracoscopy. PATIENTS AND METHOD: A total of 14 patients with congestive heart failure, NYHA functional class 3.2 (0.6) and mean ejection fraction 22.9 (6.8)% were included in this study. Left bundle branch block, QRS complex >140 ms and abnormal septal motion were observed in all cases. Epicardial leads were implanted on the left ventricular free wall under general anesthesia using video-assisted thoracoscopic surgery. RESULTS: Lead implantation was successful in 13 patients. Conversion to a small thoracotomy was necessary in one patient. All patients were extubated in the operating room. None of the patients died during their hospital stay. Follow-up showed reversal of ventricular asynchrony and significant improvement in ejection fraction and functional class. CONCLUSIONS: Minimally invasive surgery for ventricular resynchronization using video-assisted thoracoscopy in selected patients is a safe procedure that makes it possible to choose the best site for lead implantation and provides adequate short- and medium-term stimulation.

Discrepancy between stress electrocardiographic changes and nuclear myocardial perfusion defects in the prognostic assessment of patients with chest pain.

OBJECTIVES: The aim of the present study was to determine the long-term prognostic value provided by the exercise electrocardiographic (ECG) response to nuclear myocardial perfusion imaging (MPI) in the evaluation of patients with chest pain, focusing on patients with a discrepancy between the two tests. METHODS: A total of 1460 consecutive patients (777 female; 62.6 ± 11.4 years) undergoing exercise myocardial single-photon emission computed tomography (SPECT) were included. The endpoint was the occurrence of acute coronary syndrome, heart failure or cardiac death during follow-up. RESULTS: Ischemic ECG changes were observed during stress testing in 271 patients (18.5%) and 362 patients (24.7%) had positive (abnormal) exercise MPI results. There was a discrepancy between ECG and SPECT findings in 471 patients (32.2%). During the follow-up period (14.0-39.6 months), 224 patients (15.3%) presented cardiac events. The hazard ratios (HR) of ECG and MPI results to predict events were 1.506 (95% CI: 1.113-2.039) and 10.481 (95% CI: 7.799-14.080), respectively. In patients with negative MPI, the ECG response did not predict events (HR 1.214 [95% CI: 0.646-2.282]), the same as in patients with positive MPI (HR 1.203 [95% CI: 0.848-1.705]). Only in hypertensive patients with positive SPECT did the ECG show significant prognostic value (HR 1.937 [95% CI: 1.030-3.642]). In multivariate analysis, positive MPI proved an independent long-term prognostic factor (HR 10.536 [95% CI: 7.759-14.308]), but not ECG (HR 1.356 [95% CI: 0.994-1.850]). CONCLUSION: MPI results (normal vs. abnormal) had strong predictive value and discrepant ECG results had no significant additive prognostic value.

Myxoma of the aortic valve.

Myxomatous tumours can arise from different cardiac structures. They have a special predilection for the left atrium and are an exceedingly uncommon finding in cardiac valves. We report the case of a 28-year old man who presented with a stroke and was found to have a mass arising from his aortic valve. The patient underwent a successful surgical excision of the aortic valve with the implantation of a mechanical prosthesis. The histopathological examination of the aortic valve confirmed the diagnosis of myxoma. Some aspects related to the diagnosis and management of this entity are discussed in this article.

Early calcification of the aortic Mitroflow pericardial bioprosthesis in the elderly.

BACKGROUND: We report our experience in the elderly with aortic valve replacement using the Mitroflow A12 pericardial bioprosthesis. METHODS: From January 1993 to January 2006, 491 patients over the age of 70 years received an aortic Mitroflow A12 bioprosthesis implantation. Concomitant procedures included coronary artery bypass grafting in 20% of patients. All patients had routine postoperative Echo-Doppler studies at discharge, one month and a mean of 11.1 months after surgery and annually thereafter. RESULTS: Twenty (4%) patients underwent a second aortic valve replacement due to bioprosthetic valve dysfunction (Group 2). Calcified stenosis was the most common finding at reoperation (98%). Median time to valve reoperation was 76 months. Of patients requiring reoperation, median age at first and second implantation was 73 (70-78) and 79 (76-83) years, respectively. For all patients, freedom from structural valve dysfunction (SVD) was 95+/-3% at 5 years and 55.8+/-2% at 10 years. Bioprosthetic valve deterioration was identified in 27 patients (Group 1). Median age of these patients at first operation and at diagnosis of deterioration by echo was 75 (70-84) and 77 (70-82) years, respectively. The median interval between operation and detection of bioprosthesis valve deterioration was 46 months. Among the total patient population, freedom from bioprosthetic deterioration was 85.7+/-2% at 5 years and 33.5+/-4% at 10 years. CONCLUSION: The Mitroflow A12 pericardial bioprosthesis provides less than optimal performance in elderly patients.

Riesgo de asma en niños con sibilancias recurrentes, en dos hospitales del departamento de Lambayeque ­ Perú, durante agosto ­ diciembre del 2011 / Risk of asthma in children with recurrent wheezing in two hospitals of the department of Lambayeque-Perú, during the period from august to december 2011

El asma es una enfermedad cuya prevalencia es del 24% en el departamento de Lambayeque. Objetivo: Determinar riesgo de asma en niños con sibilancias recurrentes, en dos hospitales del departamento de Lambayeque, durante el período Agosto ­ Diciembre del 2011. Material y Método: Estudio descriptivo transversal, muestreo por conveniencia. Tamaño muestral: 263 niños, calculada con prevalencia del 24%, 95% de confianza, y precisión absoluta de 5%; incluyendo los casos que cumplan los criterios de inclusión y carezcan los de exclusión, identificados mediante revisión de historias clínicas, y aplicación de un cuestionario, fundamentado en el Índice Predictor de Asma. Resultados: El 36% de los sibilantes recurrentes presentaron riesgo alto para asma. El 37,8% de la población del Hospital Regional Docente Las Mercedes, y 32,5% de la población del Hospital Provincial Belén de Lambayeque presentaron riesgo alto para asma. El 34,4% de la población de sexo femenino, y 37,9% de sexo masculino, presentaron riesgo alto de asma. El 41,7% de los niños mayores de dos años presentaron riesgo alto para asma. Conclusión: El 36% de los niños con sibilancias recurrentes de dos hospitales del departamento de Lambayeque, presentaron riesgo alto para asma; sin haber diferencia significativa en cuanto al sexo y a hospital.