Effects of “Covid Vaccines” on the Immune System and the induced effects on SARS-CoV-2 Infections
Effects of “Covid Vaccines” on the Immune System and the induced effects on SARS-CoV-2 Infections
- In work and incomplete.
- To be checked.
- Often just emphasizing open questions.
Mostly written in June 2021. To updated to the current stand of published research e.g. immune responses caused by vaccines are to some extent known by now (December 2021, also many have already been known back in June but I didn’t known the publications back then).
Summary
The admitted vaccines are administrated into the muscle and mostly use the spike as antigen. This produces a strong IgG antibody response with neutralizing capabilities in vitro. People immunized like this are less likely to develop typical Covid symptoms in the first few months and there is protection against ADRS which lasts for a least half a year. Most vaccines also reduce the average viral load measured in the upper respiratory tract (mostly NPS). Less is published about other effects of spike-muscle vaccination such as the prevalence atypical infections or the durations of infections, the effect on evolution and transmission pathways of SARS-CoV-2. Here open questions emphasized and observations from other respiratory viruses are considered:
- It is observed for influenza A that once symptomatic aerosol transmission is increased
- For delta coronaviruses, vaccines have been shown to promote immune escape evolution
Introduction
At the end of the 19 century, it was observed that the blood serum can neutralize pathogens. The substances doing so were named antibodies and that the immune system part producing them is the learned immune system. Today antibodies from the blood serum are widespread used in virology, biology and immunology since they are easy to detect and they enable pathogen detection. With IgG antibodies in the spotlight other parts of the immune system get less attention though immune system has many more parts. The current admitted vaccines produce mainly high levels of spike targeting IgG antibodies. This is a different immunity than the body produces upon natural infection e.g. regarding the immune globulin response which is easily measurable, natural infections mainly induce IgA globulins targeting the viral nucleocapsid protein.
In the trials it has been shown that the Cov-spike-into-muscle vaccines induced immunity (anti spike IgG and anti spike T cells) prevents symptomatic Covid and ARDS like disease pattern. Public research has also shown that Cov-spike-into-muscle vaccinated people tend to have lower viral loads in the upper respiratory tract (mostly NPS sampling). Other effects of vaccination are less published but still relevant to determine which groups to immunize and how to optimally immunize them:
- What kind of immunity is induced by the different methods of immunisation?
For vaccines applied to the deltoid muscle the immune response is often systemic (IgG and T cells). How good it is in the middle respiratory tract is open.
- What’s the effect of the primed immunity upon infection? How the disease is changed?
A systemically primed immune system may keep the infection away from the deep lungs and prevent ARDS disease patterns. However the infection may be longer or even persistent in the bronchi.
- Are the transmission pathways changed and if yes which?
Infections in the bronchi can yield aerosol spreading while having no or few symptoms
- What effect has vaccination on the adaption and evolution of SARS-CoV-2.
Spike only vaccination produces a strong but possibly narrow immune response, which the viruses possibly outmutate (Coronavirus Immune Evasion)
Immune Responses
Immune Response upon Vaccination
- The admitted vaccinations produces at least some and often a lot of anti spike IgG.
- Usually also anti spike T cells are induced, which has been shown in the case of the Biontech vaccine.
- By independent research groups it is shown that most vaccines fail to produce IgA.
Immune Response upon Infection depending on Vaccine Status
Few is published about what happens upon infection.
- Are the IgG globulins up-scaled? Stay they constant because they are already high enough or the body judges them as not adequate against respiratory infections?
- Are the IgA globulins up-scaled? More quickly than at SARS-2 unexposed people? // It can be that the main protection of the vaccines results from the knowledge of the antibodies to target SARS-2 and mainly irrespective of the IgG levels in the blood. If that’s the case much lower doses of vaccines could be sufficient - offering near the same protection at lower risks for unwanted effects respectively causing less damage.
Disease Progression and Pattering
in work and incomplete
Background: For vaccinated people at baseline there’s much IgG but few IgA (Immune Responses). The viruses may be mainly prevented from infecting the alveoli (which corresponds to the observations that vaccines reduce the frequency of ARDS).
There are open questions, how the vaccination primed immune system alters SARS-CoV-2 infections:
- Which locations are infected? Or concretely in which specimens SARS-2 RNA is detected? In NPS samples, saliva samples, endotracheal lavage fluid, bronchoalveolar lavage fluid? E.g. it could be that mainly the bronchi are infected but not the alveoli. This is possible since the bronchial epithelium is less protected by IgG, but the alveolar cells are protected by IgG and circulating T cells.
- Is the clearance faster or slower. Longer infection durations or even persistent infections are possible in the bronchial epithelium.
Transmission
in work
Vaccination may provide preparedness which could reduces spread. However whether Covid vaccines (admitted as of 30 June 21 are mostly intramuscular vaccines which do not produce much IgA) have a reducing effect on viral shedding for a given symptom status is currently unclear (many investigations are heavily biased since vaccinated people have less reason to get a Covid test for many reasons (less likely to be hospitalized, Covid certificates often suppose vaccinated can not be infectors, …). Some investigations do uniform screening but often NPS swabs are taken which are not a good predictor for aerosol shedding.