Covid, even if healing protects us we still need to get vaccinated: that’s why
[ad_1]
We are entering the fourth year of the Covid19 pandemic, it is practically impossible not to have ever come into contact with the virus: entirely through infection or with some part of it through the vaccine. Basically most Italians (if not all) have an immune memory against Sars-CoV2, why do we still have to get vaccinated?
Why do we still have to get vaccinated?
The answer to this question comes from a meta-analysis recently published in the Lancet Infectious Diseases. Meta-analysis is a particular type of publication where several independent studies are analyzed to determine the general trend through in-depth statistical analysis. This meta-analysis aimed to summarize published data from a total of 26 studies regarding the protection offered by healing against hybrid immunity
Hybrid immunity means the immune response that occurs in a person who has recovered from Covid19 and then vaccinated (or vice versa). In this article, researchers investigated the protection conferred by recovery and hybrid immunity against reinfection or hospitalization.
What the meta-analysis published in the Lancet says
The meta-analysis shows that subjects with hybrid immunity have a lower risk of both hospitalization and infection than subjects who have only recovered. In fact, the meta-analysis underlined how hybrid immunity confers high and lasting protection against hospitalization and serious illness with an efficacy of around 96%. Furthermore, the reported data confirm that hybrid immunity also has a protective effect against infection but that this decreases over time, reaching an efficacy of about 42% after several months.
Vaccine and healing the best protection against Covid: the Lancet analysis
by Naomi Penna
The double protection
These data reflect the two levels of protection provided by our immune system: cellular response, which helps against symptoms, and humoral response, which helps against infection. Unfortunately, these are variable in the population since they are strongly dependent on the biology of the subject and some factors, such as age and comorbidities, can influence the response itself. Nonetheless, generalizing the results reported by the meta-analysis, it is clear that infection alone produces less protection than hybrid immunity and this underlines how important vaccination is.
This result shouldn’t surprise us, we know that Sars-CoV2 in our body carries out a whole series of actions to weaken our immune system which is sometimes unable to generate a robust and lasting immune response.
The immune response triggered by the infection
The immune response triggered by natural infection is extremely heterogeneous and leads to various risks including more or less serious sequelae that can be cataloged under the long covid umbrella. At the biological level, the infection exposes the immune system to a range of antigens that come from different parts of the virus, creating a more heterogeneous, less targeted response, depending on the infection itself or on the subject’s biology. And in some subjects, especially those who are not vaccinated, it may not be sufficient to provide lasting and effective protection against the symptoms deriving from a reinfection, increasing not only the risks of serious illness but also those associated with long covid.
Vaccine immunity
The vaccine instead triggers an orderly and robust immune response that is maintained in the months after the inoculation. At a biological level, most vaccines express only the Spike protein by concentrating the response against this protein. And, if we look at the scientific consensus, it’s clear how vaccination has reduced the risks of serious disease and potential sequelae in the population.
Hybrid immunity
The hybrid immunity that arises when a vaccinated person is infected confers a very high degree of protection as it is based on the two immunological events, vaccination and infection. For example, natural infection stimulates the production of IgA antibodies present in the mucous membranes of the respiratory system while the vaccine stimulates a systematic and lasting response. Furthermore, since vaccines are designed with the ancestral spike protein, hybrid immunity allows for an increase in the amplitude of the response after coming into contact with a variant different from the ancestral strain.
Does this mean that hybrid immunity should be favored because it is more effective? No. While hybrid immunity provides a robust immune response with a solid scientific consensus summarized in the meta-analysis cited, it is definitely not recommended to become infected on your own.
COVID WATCH The complete archive
Hybrid immunity cannot be a public health measure
Hybrid immunity is not a public health measure but rather a biological event that in the current situation can happen and it is necessary to report continuously developing scientific evidence analyzing this event. I would like to underline that every single infection or reinfection constitutes a risk which, although it can be mitigated by a trained immune system and can vary according to the biology of the subject, remains present. Therefore it is not recommended to get infected to acquire better immunity but on the contrary, a person should protect himself from the infection or try to mitigate the number of infections by the methods he deems necessary.
To conclude, this meta-analysis confirms the importance of vaccination for recovered subjects who should be vaccinated according to the methods established by the Ministry of Health.
The article was written with Stefano Berto, biologist and assistant professor at the Medical University of South Carolina.
TAKE HOME MESSAGES:
- hybrid immunity is formed in a recovered and vaccinated subject
- hybrid immunity offers greater protection than single healing
- hybrid immunity confers a very good degree of protection against hospitalization and infection, although the latter declines over time.
- hybrid immunity is not a public health measure and becoming infected is not recommended
- hybrid immunity is a biological event and as such must be analysed
- recovered subjects should be vaccinated according to the methods indicated by the Ministry of Health
REF:
https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(22)00801-5/fulltext
https://www.salute.eu/2022/05/09/news/vaccinati_e_infettati_la_scoltazione-348353658/
Aureliano Stingi, doctor in molecular biology works in the field of precision oncology. He collaborates with the World Health Organization in the battle against Covid19-themed fake news
Instagram: Aureliano _Stingi Twitter: @AurelianoStingi
[ad_2]
Source link
