SARS-CoV-2: previous coronaviruses, immune response, and development of vaccines / SARS-CoV-2: coronavirus previos, respuesta inmune y desarrollo de vacunas

Abstract Since the emergence of the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China at the end of 2019, when its characteristics were practically unknown, one aspect was evident: its high contagion rate. This high infection rate resulted in the spread of the virus in China, Europe, and, eventually, the rest of the world, including Mexico. At present, around 9 million people are infected, and around 470,000 have died worldwide. In this context, the need to generate protective immunity, and especially the generation of a vaccine that can protect the world population against infection in the shortest possible time, is a challenge that is being addressed in different countries using different strategies in multiple clinical trials. This opinion article will present the evidence of the induction of immune response in some of the viruses of the coronavirus family before COVID-19, such as SARS-CoV and MERS-CoV (Middle East respiratory syndrome coronavirus). The information collected about the induction of an immune response by SARS-CoV-2 will be presented, as well as a description of the vaccine candidates reported to date in the various ongoing clinical trials. Finally, an opinion based on the evidence presented will be issued on the potential success of developing vaccine prototypes.

Resumen Desde el surgimiento del nuevo coronavirus SARS-CoV-2 (coronavirus tipo 2 del síndrome respiratorio agudo severo) en China a finales del año 2019, cuando todavía era desconocido prácticamente en todos los aspectos, una característica era evidente: el alto índice de contagio entre la población. Esto resultó en la expansión del virus en China, Europa y, finalmente, en el resto del mundo, incluyendo México. Actualmente, alrededor de 9 millones de personas están infectadas, y han muerto cerca de 500,000 en todo el mundo. En este contexto, la necesidad de generar inmunidad protectora y, sobre todo, el desarrollo de una vacuna que pueda proteger a la población mundial contra la infección en el menor tiempo posible, es un reto que se está abordando en distintos países utilizando diversas estrategias en múltiples ensayos clínicos. En este artículo de opinión se presentan las evidencias de la inducción de respuesta inmunitaria con algunos de los virus de la familia de coronavirus previos al SARS-CoV-2, como el SARS-CoV (coronavirus del síndrome respiratorio agudo severo) y el MERS-CoV (síndrome respiratorio por coronavirus de Oriente Medio). Además, se presenta lo reportado hasta el momento acerca de la inducción de respuesta inmunitaria por el SARS-CoV-2, así como una descripción de los candidatos a vacunas informados hasta el momento en los distintos ensayos clínicos en curso. Finalmente se emite una opinión, basada en las evidencias presentadas, acerca del éxito potencial de los prototipos de vacunas en desarrollo.

Terapia medicamentosa para infecções por coronavírus em humanos: revisão sistemática rápida / Pharmacological therapies for patients with human coronavirus infections: a rapid systematic review

Resumo O objetivo deste trabalho foi avaliar efeitos de tratamentos medicamentosos para infecções por coronavírus. Revisão sistemática rápida com buscas nas bases MEDLINE, EMBASE, Cochrane, BVS, Global Index Medicus, Medrix, bioRxiv, Clinicaltrials.gov e International Clinical Trials Registry Platform. Foram incluídos 36 estudos avaliando alternativas medicamentosas contra SARS, SARS-CoV-2 e MERS. A maioria dos estudos incluídos foi conduzida na China com delineamento observacional para tratamento da COVID-19. Os tratamentos mais estudados foram antimaláricos e antivirais. Nos antimaláricos, a metanálise de dois estudos com 180 participantes não identificou benefício da hidroxicloroquina em relação à negativação da carga viral via reação em cadeia de polimerase em tempo real e o uso de antivirais comparado ao cuidado padrão foi similar em relação aos desfechos. As evidências científicas disponíveis são preliminares e de baixa qualidade metodológica, o que sugere cautela na interpretação dos dados. Pesquisas que avaliem a eficácia comparativa em ensaios clínicos randomizados, controlados, com tempo de acompanhamento adequado e com os métodos devidamente divulgados e sujeitos à revisão científica por pares são necessárias. Recomenda-se atualização periódica da presente revisão.

Abstract This work aimed to evaluate the effects of drug therapies for coronavirus infections. Rapid systematic review with search in the MEDLINE, EMBASE, Cochrane, BVS, Global Index Medicus, Medrix, bioRxiv, Clinicaltrials.gov and International Clinical Trials Registry Platform databases. Thirty-six studies evaluating alternative drugs against SARS, SARS-CoV-2 and MERS were included. Most of the included studies were conducted in China with an observational design for the treatment of COVID-19. The most studied treatments were with antimalarials and antivirals. In antimalarial, the meta-analysis of two studies with 180 participants did not identify the benefit of hydroxychloroquine concerning the negative viral load via real-time polymerase chain reaction, and the use of antivirals compared to standard care was similar regarding outcomes. The available scientific evidence is preliminary and of low methodological quality, which suggests caution when interpreting its results. Research that evaluates comparative efficacy in randomized, controlled clinical trials, with adequate follow-up time and with the methods properly disclosed and subject to scientific peer review is required. A periodic update of this review is recommended.

Eficácia da máscara facial (TNT) na população para a prevenção de infecções por coronavírus: revisão sistemática / Effectiveness of the use of non-woven face mask to prevent coronavirus infections in the general population: a rapid systematic review

Resumo O objetivo deste artigo é avaliar a eficácia das máscaras faciais padrão tecido não tecido (TNT) para a prevenção de doenças respiratórias (MERS CoV, SARS-CoV e SARS-CoV-2) na população. Foi realizada busca nas bases de dados Medline, Embase, Cinahl, The Cochrane Library, Trip. Também busca complementar no Google Acadêmico, Rayyan e medRxiv. Não foram aplicados filtros relacionados a data, idioma ou status de publicação. Títulos e resumos foram rastreados e, posteriormente, textos completos foram avaliados. Foram incluídos três estudos: um ensaio clínico randomizado tipo cluster e duas revisões sistemáticas. O ensaio clínico indica benefício potencial de máscaras médicas para controle da fonte de infecção, para a doença respiratória clínica. Em uma das revisões sistemáticas, não foi possível estabelecer relação conclusiva entre uso da máscara e proteção contra infecção respiratória. Por fim, outra revisão sistemática demonstrou que máscaras são eficazes na prevenção da propagação de vírus respiratórios. As evidências apontam para benefício potencial das máscaras faciais padrão TNT. Para o cenário atual de pandemia por COVID 19, recomenda-se educação sobre uso adequado de máscaras, associado a medidas individuais de proteção.

Abstract Objectives: to evaluate the effectiveness of non-woven face masks for the prevention of respiratory infections (MERS CoV, SARS-CoV, and SARS-CoV-2) in the population. Methods: search in Medline, Embase, Cinahl, The Cochrane Library, Trip databases. Google Scholar, Rayyan and medRxiv were also consulted for complementary results. No filters related to date, language or publication status were applied. Titles and abstracts were screened, and later, full texts were evaluated. Results: three studies were included: a randomized cluster clinical trial and two systematic reviews. The clinical trial indicates a potential benefit of medical masks to control the source of clinical respiratory disease infection. In one of the systematic reviews, it was not possible to establish a conclusive relationship between the use of the mask and protection against respiratory infection. Finally, another systematic review indicated that masks are effective in preventing the spread of respiratory viruses. Conclusion: Evidence points to the potential benefit of standard non-woven face masks. For the current pandemic scenario of COVID-19, education on the appropriate use of masks associated with individual protection measures is recommended.

Better Understanding on MERS Corona Virus Outbreak in Korea

No abstract available.

Middle East Respiratory Syndrome Coronavirus Superspreading Event Involving 81 Persons, Korea 2015

Since the first imported case of Middle East respiratory syndrome coronavirus (MERS-CoV) infection was reported on May 20, 2015 in Korea, there have been 186 laboratory-confirmed cases of MERS-CoV infection with 36 fatalities. Ninety-seven percent (181/186) of the cases had exposure to the health care facilities. We are reporting a superspreading event that transmitted MERS-CoV to 81 persons at a hospital emergency room (ER) during the Korean outbreak in 2015. The index case was a 35-yr-old man who had vigorous coughing while staying at the ER for 58 hr. As in severe acute respiratory syndrome outbreaks, superspreading events can cause a large outbreak of MERS in healthcare facilities with severe consequences. All healthcare facilities should establish and implement infection prevention and control measure as well as triage policies and procedures for early detection and isolation of suspected MERS-CoV cases.