Covid-19 has registered five variants so far. The first is called Alpha and was registered in the UK in September 2020, the second, Beta, was registered in October 2020 in South Africa; the third is the Gamma variant and it appeared for the first time in Brazil in December 2020. In October 2020 the Delta variant was registered in India and finally we have the Omicron variant, which appeared for the first time on 11 November 2021.
As new variants were identified, the dissemination capacity increased more and more, up to the Delta variant, first detected in Brazil in December 2020, which according to various experts has a dissemination capacity ranging from 43% 90% of the previous ones. The Omicron variant would seem to confirm this trend: just think that in just two weeks in South Africa its contagiousness went from 1% to 30%.
Severity of the disease
Already with the Delta variant, an AIFA study published last August 27 had shown a 50% increase in the probability of a person being hospitalized in intensive care. While there are still conflicting studies on the other variants. As for the Omicron variant – as explained by Dr. Angelique Coetzee, who discovered the mutation in South Africa – there are the classic symptoms such as fatigue, headache, itching in the throat and a slight cold, but in terms of severity they are not serious cases have still been found.
Effectiveness of vaccines
As for the efficacy of vaccines, in the Alpha and Beta variants there is a greater ability to counteract antibodies, while for the Gamma variant, several studies speak of a good probability of reinfection. Vaccine protection declines further with the Delta variant, where a greater likelihood of ICU admission has been recorded. Finally, as regards Omicron, being a new variant, there is not yet sufficient data that can give clear indications in this regard.
The graphics are edited by Vincenzo Monaco
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