COVID-19 vaccines: ethical framework concerning human challenge studies.

BACKGROUND: The pandemic associated with the new SARS-CoV-2 coronavirus continues to spread worldwide. The most favorable epidemic control scenario, which provides long-term protection against COVID-19 outbreak, is the development and distribution of an effective and safe vaccine. The need to develop a new COVID-19 vaccine is pressing; however, it is likely to take a long time, possibly several years. This is due to the time required to demonstrate the safety and efficacy of the proposed vaccine. and the time required to manufacture and distribute millions of doses. OBJECTIVES: To accelerate this development and associated safety testing, the deliberate infection of healthy volunteers has been suggested. The purpose of this short communication is to describe the ethical aspects of this type of testing, RESULTS: Deliberate infection of volunteers with a dangerous virus such as SARS-CoV-2 was initially considered unethical by researchers; but the current pandemic is so different from previous ones that these studies are considered ethical if certain criteria are met. Participants in human challenge studies must be relatively young, in good health and must receive the highest quality medical care, with frequent monitoring. Tests should also be performed with great caution and specialized medical supervision. Besides, the fact that obtaining vaccines faster through deliberate infection studies of healthy people has greater benefits than risks, has been demonstrated by obtaining other vaccines in other historical pandemics such as: smallpox, influenza, malaria, typhoid fever, Dengue fever and Zika. CONCLUSIONS: One possibility to shorten the time required for the development of COVID-19 vaccines is to reduce clinical phases II and III by using human challenge studies through eliberate infection of healthy volunteers with SARS-CoV-2 after administration of the candidate vaccine. Accelerating the development of a COVID-19 vaccine even for a few weeks or months would have a great beneficial impact on public health by saving many lives.

Towards effective COVID­19 vaccines: Updates, perspectives and challenges (Review).

In the current context of the pandemic triggered by SARS-COV-2, the immunization of the population through vaccination is recognized as a public health priority. In the case of SARS­COV­2, the genetic sequencing was done quickly, in one month. Since then, worldwide research has focused on obtaining a vaccine. This has a major economic impact because new technological platforms and advanced genetic engineering procedures are required to obtain a COVID­19 vaccine. The most difficult scientific challenge for this future vaccine obtained in the laboratory is the proof of clinical safety and efficacy. The biggest challenge of manufacturing is the construction and validation of production platforms capable of making the vaccine on a large scale.

Tick-Borne Encephalitis Electrochemical Detection by Multilayer Perceptron on Liquid-Metal Interface.

This work depicts an electrochemical hydrogel-eutectic gallium indium alloy interface for the detection of tick-borne encephalitis (TBE) virus. This interface allows recording of nonlinear current-voltage responses, depending on the composition of the hydrogel. The current-voltage data for the machine learning model are trained by a multilayer perceptron. This model accurately recognizes the TBE antibody, antigen, and an antibody-antigen complex in mixture with interfering bovine serum albumin with 93% accuracy. Thus, this interface can be used as a convenient method for expressed viruses and pathogens detection.