COVID-19 vaccines: virologist Prof. Christian Bréchot discusses vaccine creation [fr]

Christian Bréchot, MD, PhD joined the USF Health Morsani College of Medicine part-time as Senior Associate Dean for Research in Global Affairs, Associate Vice President for International Partnerships and Innovation, and Professor in the Division of Infectious Disease, Department of Internal Medicine. He is also executive director of the Tampa-based Romark Laboratories Institute for Medical Research. Since 2017, Dr. Brechot has served as President of the Global Virus Network, a network of 48 research centers worldwide, headquartered in Baltimore.
Dr. Brechot has been the member of numerous scientific committees and societies and has received prestigious awards. We asked him a few of the most common questions that arise in regard of the current pandemic and vaccination campaign.

As a virologist and former President of the Institut Pasteur (historical pioneer in human vaccination), can you remind our readers of the impact of the emergence and development of vaccination on the population?

Vaccination against COVID-19, as with any infectious disease, will be a determining factor in containing this pandemic. That being said, we must not forget that, in addition to the problem of delays in the production and supply of doses, it is the association of vaccination with protective measures (wear a mask, practice physical distancing and wash hands frequently) as well as diagnostic tests and new treatments being evaluated for the prevention and treatment of forms with few symptoms, which will be effective.

In all countries, a large part of the population expresses fears about the vaccines made to counter the COVID-19 virus, in particular because of its faster than usual creation. What can you tell us to reassure these people?

Firstly, RNA vaccines are the result of at least 20 years of research. The first phase trials had been carried out by the company Moderna for the Zika virus. It is therefore the application to vaccination of extensive and relatively old research.

In addition, the procedures for evaluating these vaccines by regulatory agencies were the same as for other vaccines. It is the agenda for these assessments that has been accelerated. There was no "free pass" and these assessments were carried out by rigorous and independent scientific committees.

Finally, to date, more than 16 million people have received the vaccines. Serious incidents are rare (around 20 cases per 3 million people vaccinated): they are allergic reactions that most often occur in people with a history of severe allergies, and none of these reactions had serious consequences. In these cases, prior medical advice and monitoring of approximately 15-30 minutes after the administration of the dose are recommended as incidents always occur within approximately 15 minutes.

The other question asked regularly is the protection of this vaccine against the new "variants" of the virus. Are the vaccines produced today effective against these new forms of the virus?

Vaccines generate the production of antibodies against multiple sites in the envelope protein of the virus (spike); they therefore remain effective against the "variants" described so far even if certain mutations must be particularly monitored (so-called "South African" and "Brazilian" variants). Moreover, in addition to humoral immunity (production of antibodies), vaccines stimulate – in a variable way depending on the vaccine – a cellular immunity that we do not measure routinely but which will perhaps prove to be very important for the control of these "variants".

On the other hand, the mutations observed in these "variants" can affect the efficiency of treatment with monoclonal antibodies against the virus, which target only one site of the spike protein, a treatment proposed to treat COVID19 in its early phase or even prevent infection.

There has also been an upsurge in infectious diseases passing from animals to humans. What are the main reasons for these accelerated transmissions and the solutions that could be implemented to fight against this phenomenon?

There is indeed an acceleration in the transmission of viral infections from animals to humans ("Zoonoses"); this is due to increasing urbanization, deforestation and human migration. The important consequence of these observations for the prevention of future pandemics is the need to focus epidemiological surveillance more on human populations in contact with animals.

Christian Bréchot, MD, Ph.D.


Before serving as president of the Pasteur Institute from 2013 to 2017, Dr. Bréchot was vice president of medical and scientific affairs at Institut-Merieux, a company that develops new approaches to fight infectious diseases and cancers. He also served as the general director of Inserm, the French national agency for biomedical research from 2002 to 2007. As professor of hepatology and cell biology at Necker School of Medicine, Paris Descartes University, he led the clinical department of liver diseases at Necker-Enfants Maldes Hospital from 1997 to 2001.

Authoring more than 400 articles in medical and scientific journals, Dr. Bréchot was ranked by the Institute for Scientific Information as the 4th most cited author on the topic of hepatitis C. He has been recognized as an inventor on 18 patents, and helped create three biotechnology companies: Rarecells, ALFACT Innovation, and The Healthy Aging Company.

Dr. Bréchot’s research activities have focused on viral hepatitis: hepatitis B (HBV) and C (HCV), particularly with regard to their role in liver cancer (Hepatocellular carcinoma: HCC) and to the molecular mechanisms that drive liver regeneration and cancer (in particular, cell cycle deregulation and the impact of oxidative stress).

Finally, Dr. Bréchot’s research interests include microbiomes, particularly in the area of microbiomes and viral infections. In this respect, he is a co-founder of the Microbiome, Immunology and Infection Control (MIIM) in the USF Pandemic Response Research Network (PRRN). This research hub focuses on enabling and connecting an interdisciplinary network of scientists at USF and globally. The hub’s goals are to develop precision therapies and interventions that target the human microbiome to maintain and restore human health against COVID-19 and future such pandemics. Dr. Brechot is also the head of the USF Initiative on Microbiomes.

Last modified on 29/01/2021

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