Organizational experience of the Civil Defense Scientific Research Center in the diagnosis of COVID-19

Facing the COVID-19 epidemic in Cuba has required the development of new capacities for its diagnosis in the molecular biology laboratories of different scientific and health institutions. The objective of this work is to show the experience of the Cuban Civil Defense Scientific Research Center in organizing the diagnosis of COVID-19. Guiding documents for the Center's work, its biosafety program, and those reported by the World Health Organization for dealing with the pandemic were reviewed. The experience of the structure adopted by the entity to ensure an uninterrupted diagnosis, the functions of the Steering Group and the sequence of activities carried out is exposed; highlighting the training of personnel in the management of biological risks and the prevention measures adopted. The proper use of collective and individual protection means, the safe handling of biological samples and cooperation with other entities, have allowed the fulfillment of the entrusted task, without the occurrence of accidents that compromise the health of the personnel working in the diagnosis, nor effects on the community and the environment

Caracterización genética de aislamientos de SARS-CoV-2 en las diferentes etapas pandémicas de COVID-19 en Cuba

Introducción: El desarrollo de vacunas seguras y eficaces contra el SARS-CoV-2 supuso un enorme reto para enfrentar la pandemia de la COVID-19. La aparición de nuevas variantes del SARS-CoV-2 representa un reto en la evaluación de la efectividad de las vacunas, diferentes candidatos vacunales y terapéuticos desarrollados por la comunidad científica. Objetivos: Caracterizar la diversidad genética de aislamientos virales cubanos en el periodo comprendido entre junio de 2020 y diciembre de 2022. Métodos: Se obtuvo el ARN de SARS-CoV-2 de 27 aislamientos a partir de sobrenadante de cultivo celular y se secuenció el gen S. Las secuencias generadas se emplearon para la identificación y posterior caracterización molecular de las variantes genéticas del virus mediante análisis filogenético y el uso de las herramientas disponibles en la base de datos GISEAD. Resultados: Las variantes detectadas en los aislamientos cubanos de SARS-CoV-2 estudiados se correspondieron a las identificadas en los estudios de vigilancia genómica realizados en las diferentes etapas pandémicas de la COVID-19 en Cuba. El 33,3 % de los aislamientos secuenciados correspondieron a los diferentes linajes de la variante Ómicron, seguido de la variante Beta B 1.351 (29,6 %), otros linajes de SARS-CoV-2 (25,9 %), Alfa B 1.1.7 (7,4 %) y Delta B.1.575 (3,7 %). Se detectó la mutación D614G en todos los aislamientos de SARS-CoV-2 estudiados. Conclusiones: La caracterización molecular de los aislamientos cubanos de SARS-CoV-2 tiene una elevada diversidad genética. Posibilita evaluar in vitro e in vivo los candidatos vacunales y agentes terapéuticos desarrollados por la industria biofarmacéutica cubana

Open-label phase I/II clinical trial of SARS-CoV-2 receptor binding domain-tetanus toxoid conjugate vaccine (FINLAY-FR-2) in combination with receptor binding domain-protein vaccine (FINLAY-FR-1A) in children

Objectives: To evaluate a heterologous vaccination scheme in children 3-18 years old (y/o) combining two SARS-CoV-2r- receptor binding domain (RBD)protein vaccines. Methods: A phase I/II open-label, adaptive, and multicenter trial evaluated the safety and immunogenicity of two doses of FINLAY-FR-2 (subsequently called SOBERANA 02) and the third heterologous dose of FINLAY-FR-1A (subsequently called SOBERANA Plus) in 350 children 3-18 y/o in Havana Cuba. Primary outcomes were safety (phase I) and safety/immunogenicity (phase II) measured by anti-RBD immunoglobulin (Ig)G enzyme-linked immunoassay (ELISA), molecular and live-virus neutralization titers, and specific T-cells response. A comparison with adult immunogenicity and predictions of efficacy were made based on immunological results. Results: Local pain was the unique adverse event with frequency >10%, and none was serious neither severe. Two doses of FINLAY-FR-2 elicited a humoral immune response similar to natural infection; the third dose with FINLAY-FR-1A increased the response in all children, similar to that achieved in vaccinated young adults. The geometric mean (GMT) neutralizing titer was 173.8 (95% confidence interval [CI] 131.7; 229.5) vs Alpha, 142 (95% CI 101.3; 198.9) vs Delta, 24.8 (95% CI 16.8; 36.6) vs Beta and 99.2 (95% CI 67.8; 145.4) vs Omicron. Conclusion: The heterologous scheme was safe and immunogenic in children 3-18 y/o. Trial registry: https://rpcec.sld.cu/trials/RPCEC0000037