Coronavirus: 7 questions about the vaccine
The current pandemic is unlikely to stop with a miracle vaccine. But working on this type of preventive product remains a necessity to prepare for a possible new wave of infection. Find out everything you need to know about the vaccine career that is shaking up medical research.
Vaccines are essential to stop the coronavirus pandemic, but they are not an overnight solution. As part of the Covid-19 epidemic, scientists around the world are working hard to develop an effective and safe product in the shortest time possible.
What is the difference between an antiviral and a vaccine?
Antiviral treatments are drugs used to treat an illness early and prevent it in certain specific cases. They help alleviate symptoms, decrease duration and illness, and therefore prevent certain complications. An antiviral does not immunize the patient but reduces the reproductive capacity of the virus.
A vaccine, on the other hand, helps immunize the patient by stimulating the production of antibodies against a particular virus. Therefore, it is a preventive tool for the disease. From a medical research perspective, it takes longer to develop a vaccine than an antiviral because the time it takes to observe the immune response, as well as to study the efficacy, takes longer. For an antiviral, the result of a clinical trial is faster.
What are the steps to create a vaccine?
A vaccine is made from the germs (viruses, bacteria, or parasites) that it will work against. "The manufacturing processes are often long and complex. In fact, it takes between six and twenty-two months to produce a vaccine against a few weeks to six months in general for chemical drugs," says the Vaccin-Info-Service site. Most of the manufacturing time is devoted to quality and safety control for each step of the process.
To produce the active substance, researchers must build a germ bank, cultivate it, amplify it, extract the antigen, purify it and concentrate it through physical processes such as centrifugation. In some cases, it is necessary to inactivate the substance produced by heat or chemical agents. The different substances are combined into a single compound.
To obtain the final product that will be offered in pharmacies, it is necessary to add elements such as adjuvants, stabilizers and preservatives, distribute everything in vials or syringes, possibly lyophilize the product and condition it. It will then be reviewed by the industry and an independent authority before being placed on the market.
What has been done to speed up the process?
In light of the current situation and the unprecedented epidemic, health authorities have made efforts to help scientists around the world focus their efforts on developing a vaccine. Since the first Sars-Cov-2 gene sequence was made available, about thirty startups and companies have been working full time.
Tests are also being carried out to measure the effects of the tuberculosis vaccine (BCG), which has the advantage of being well known (more than 3 billion people vaccinated worldwide) on covid-19 disease. Inserm is preparing to establish a double blind French clinical trial. But participants should be followed for 2 to 3 months to have reliable data.
How long should it take?
However, scientists caution that it takes between one and two years of research to come up with a finished product. For the most optimistic, a first vaccine may be available in late 2020.
Is it dangerous to skip steps?
A poorly designed vaccine is potentially dangerous. It is a virus that is injected into the body, which may facilitate infection rather than prevent it. This is why researchers face additional pressure, in addition to time pressure, regarding the safety of the finished product.
Why work on a vaccine that will come out after the epidemic?
Vaccines are essential to treat a virus, although it is very difficult to eradicate it completely. The risk for the population is to face several waves of epidemics.
People who were not infected the first time can get sick, and the epidemic can start again. That's why having a vaccine available can help limit the damage.
The Covid-19 tends to remain stable. Good or bad news?
The seasonal flu virus tends to mutate regularly, so the vaccine needs to be changed every year. However, according to Italian and American researchers who analyzed SARS-CoV-2, this virus has only registered five mutations in a few months, despite its large-scale displacement. PoTherefore, it is considered stable.
This feature would allow the maximum effectiveness of a possible vaccine. If these small mutations do not multiply, a single vaccine could even be used for several years.