Risks of low vaccination coverage and strategies to prevent the resurgence of vaccine-preventable diseases in infants in the COVID-19 pandemic scenario: recommendations for Latin America and the Caribbean by the group of experts on infant immunization for Latin America.

INTRODUCTION: The WHO 2030 Immunization Agenda (IA-2030) harmonizes immunization activity plans at community, national, regional and global levels. Additionally, medical societies play an important role. The Latin American Group of Experts on Infant Immunization, established in 2018, advises on the harmonization, update, and optimization of infant vaccination programs in Latin America and the Caribbean (LAC). In September 2021, 41 such experts from 13 LAC countries met to develop recommendations for increasing regional vaccination coverage to avoid the reemergence of vaccine-preventable diseases and/or the occurrence of outbreaks. AREAS COVERED: The following items were evaluated: (i) immunization challenges before and during the COVID-19 pandemic; (ii) the status of current immunization programs, particularly infant pertussis and polio vaccination; (iii) possible solutions for overcoming vaccination challenges and achieving regional vaccination coverage targets. EXPERT OPINION/COMMENTARY: Medical societies provide valuable recommendations to guide and update vaccination schedules. In the LAC region, possible strategies to achieve target vaccination rates include the use of combination vaccines, strengthening surveillance systems, improving school attendance, advancing vaccine education and confidence, striving for vaccination equity, widening operational capacity, creating strategic alliances, and strengthening the role of medical groups. It is hoped that these recommendations will be implemented in the LAC region.

[SARS CoV-2 Vaccine studies currently in phase III]. / Vacunas SARS CoV-2, estudios en fase III.

The coronavirus disease 2019, caused by the SARS-CoV2 virus, was declared a pandemic in March 2020 by the WHO. Protein S from the viral surface has been identified as the optimal antigen for vaccine development. In a pandemic, the traditional vaccine development process has had to be accelerated to advance in an adequate response to the problem, shortening the times. Safety, immunogenicity, protection against infection, antibody dependent enhancement phenomena and duration of protection are studied in parallel, unlike the traditional way in which it was carried out in successive stages. Currently in Phase III there are 4 types of vaccines: inactivated; based on purified or recombinant proteins, based on DNA / RNA nucleic acids and based on viral vectors. The objective of this review is to understand the studies that precede the vaccines that are currently in Phase III studies and to describe the main characteristics of these studies. Currently the world is in a situation unprecedented in the last century. Among the options to face this fact, one vaccine or, ideally, several, safe, effective and immunogenic, seem to be one of the best alternatives to regain lost normality within a reasonable time.

Vacunas SARS CoV-2, estudios en fase III / SARS CoV-2 vaccine studies currently in phase III

Resumen La enfermedad por coronavirus 2019, causada por el virus SARS-CoV2, fue declarada pandemia en marzo de 2020 por la OMS. La proteína S, de la superficie viral ha sido identificada como antígeno óptimo para el desarrollo de vacunas. En pandemia, el proceso tradicional de desarrollo de vacunas ha debido acelerarse para avanzar en una respuesta adecuada al problema, acortando los tiempos. La seguridad, inmunogenicidad, protección frente a la infección, fenómeno de "aumento dependiente de anticuerpos", duración de la protección se estudian en paralelo, a diferencia de la manera tradicional en que se llevaba a cabo en etapas sucesivas. Actualmente en Fase III hay 4 tipos vacunas: inactivadas; en base a proteínas purificadas o recombinantes, en base a ácidos nucleicos ADN/ARN y en base a vectores virales. El objetivo de esta revisión es conocer los estudios que preceden a las vacunas que actualmente están en estudios de Fase III y describir las características principales de estos estudios. Actualmente el mundo se encuentra en una situación inédita en el último siglo. Dentro las opciones para enfrentar este hecho, una vacuna o idealmente varias, seguras, eficaces e inmunogénicas, parecen ser una de las mejores alternativas para retomar en un plazo razonable la normalidad perdida.

Abstract The coronavirus disease 2019, caused by the SARS-CoV2 virus, was declared a pandemic in March 2020 by the WHO. Protein S from the viral surface has been identified as the optimal antigen for vaccine development. In a pandemic, the traditional vaccine development process has had to be accelerated to advance in an adequate response to the problem, shortening the times. Safety, immunogenicity, protection against infection, antibody dependent enhancement phenomena and duration of protection are studied in parallel, unlike the traditional way in which it was carried out in successive stages. Currently in Phase III there are 4 types of vaccines: inactivated; based on purified or recombinant proteins, based on DNA / RNA nucleic acids and based on viral vectors. The objective of this review is to understand the studies that precede the vaccines that are currently in Phase III studies and to describe the main characteristics of these studies. Currently the world is in a situation unprecedented in the last century. Among the options to face this fact, one vaccine or, ideally, several, safe, effective and immunogenic, seem to be one of the best alternatives to regain lost normality within a reasonable time.