“With protection against a virus, you help the body to fight the virus as good as possible. If people are already sick, you do this with the regular administration of antibodies. You give, as it were, an extra dose on top of the antibodies that the body already produces. This reduces the amount of virus and dampens the symptoms of the disease. Antibodies have a temporary effect and you must therefore continue to administer them until the immune system takes over. ”
Preferably you want to protect people for a longer period, so that they cannot get sick when contamination occurs; then one speaks of a vaccine. You give the body a taste of the virus, so that contact with the real virus no longer results in illness. You have roughly three methods:
Whole-killed virus vaccines – you grow the virus and then inactivate it using heat, chemicals or radiation. You inject that inactivated and therefore harmless virus into humans to elicit an immune response.
Life-attenuated virus vaccines – an attenuated variant of the virus, which is developed in the lab by growing it continuously, or by removing certain parts of the genetic code. That attenuated virus is raised and purified and you bring it into humans to trigger an immune response.
“It is difficult with the above classic methods: they require that you cultivate the virus in large quantities. But with dangerous viruses, such as Ebola, Marburg, Niphah or this corona virus, you prefer not to do so because of the risk of infection. The risk of working with such viruses in such quantities is far too great. That is why a third method has also been developed:
Vector vaccines – A small piece of DNA from the dangerous virus is introduced into the DNA of a relatively harmless virus, such as the adeno or measles virus. This harmless virus is cultivated and purified. When injecting this vaccine into humans, the harmless virus (the vector) will bring the DNA of the dangerous virus into the human cell. There, humans develop an immune response to the dangerous virus.
The piece of DNA from the dangerous virus used in a vector vaccine is almost always the so-called SPIKE protein. Menzo Havenga explains that the body often responds the most strongly to the SPIKE protein, because this virus protein allows the virus to enter the human cell. With the corona virus, these are the bulges you see in photos. In a natural immune response, antibodies are also made against the SPIKE protein. They block binding to human cell receptors.