There are hundreds, if not thousands, of mutants and variants. Not all of them were noteworthy, many were simply harmless. Those who have mostly occupied us in the past two years of the pandemic and the last waves are also those who have been classified as questionable by organizations and authorities nationally and internationally.
- wild type
The “wild type” refers to the original Sars-CoV-2 variant, which was first registered in December 2019 in the central Chinese metropolis of Wuhan and from there spread all over the world. All others since then have to be measured against the symptoms of the first one. The virus variant, which was completely new at the time, defined the term Covid worldwide. Main symptoms: fever, cough and loss of taste and smell. Where this disease really came from – whether it was, for example, a jump from animal to human – cannot be said with certainty, even more than two years after the start of the pandemic. The wild type has practically disappeared in Austria and also plays almost no role internationally.
- alpha
The “alpha” variant (B.1.17.1 mutation) of the Sars-CoV-2 virus spread from Great Britain to Europe in autumn 2020. It came off as a “tweaked” version of the wild-type: only minimal changes to the spike protein gave the virus a better hold on the ACE-2 receptor, making the alpha variant up to 90 percent more contagious than its predecessor. In addition, this was accompanied by a higher viral load, which increased the duration of the disease. The symptoms remained unchanged. For the first time, more severe courses of the disease were registered in children.
- beta
The first cases of the beta variant (B.1.351 mutation), which originated in South Africa, were recorded in Europe as early as May 2020. Beta was found to be a little more than 50 percent more contagious than wild-type and also appeared to inhibit antibody formation. Re-infections were also quickly reported. “Beta” caused concern: The effect of the vaccinations already in use at that time was promising against “alpha”, but due to the ability of the variant to inhibit antibody formation, it was significantly reduced against “beta”.
Ultimately, the variant did not catch on in Europe. “Alpha” already dominated from late autumn 2020.
- gamma
In contrast, the “Gamma” variant (P.1), which was first registered in Brazil in December 2020, had hardly any influence in Europe. “Gamma” is similar to the “beta” variant that appeared in South Africa in its ability to inhibit antibody formation. Since the health system, especially in the Amazon region, was significantly more heavily burdened by the corona pandemic than the European systems, there is hardly any reliable data available on the course and severity of the disease.
- delta
The “Delta” variant rampant in India from October 2020 (B.1.617.2) ultimately established itself very quickly worldwide as the dominant mutation for a longer period of time. Compared to the wild type, it is significantly more contagious and leads to a significantly more severe course of the disease. The World Health Organization (WHO) immediately classified “Delta” as “concerning”. The variant is very likely to be more resistant to antibodies again. Compared to the wild type, “Delta” had 15 mutations on the spike protein. The appearance also changed symptomatically: the previously classic symptoms such as fever, cough and the loss of the sense of smell and taste increasingly faded into the background. Headaches and colds now dominated the clinical picture.
The effect of the common vaccines was put to the test again: they had a reduced effect on “Delta” than on the “Alpha” variant, which had been dominant until then.
- omicron
In November 2021, doctors in Botswana registered a completely new Sars-CoV-2 type for the first time. “omicron” (BA.2) permanently changed the appearance of the virus. The variant spread faster than any of its predecessors. Compared to the wild type, Omicron has more than 30 mutations in the spike protein – more than all variants so far. The Omicron variant has several sub-types, none of which are classified as more dangerous. The “BA.2” type is currently dominant in Europe. It is more likely to affect the mouth and throat than in the wild type, where the focus of the infection was in the lower respiratory tract. Typical symptoms are a sore throat, runny nose or swollen lymph nodes in the neck. Some of the loss of smell and taste also seems to be back – albeit still to a very small extent. In addition, the incubation time is significantly shorter compared to the previous variants. An incubation period of up to six days was previously considered a guideline, but the period has been reduced to up to three days due to study results.
Source: Nachrichten
