Alpha, Beta, Lambda, Mu … What happened to the previous variants?

While the Omicron variant is causing global concern, it is returning to the different paths of other types that have caused concern in recent months.

According to the World Health Organization, the Omigron variant presents a “very high global risk” which it has classified as “worrying”. Before Omicron, other types aroused the concern of world authorities, four of which were classified Variations of anxiety By whom.

The other four are “worrying” types

This is the name given to the English variant that was first discovered on December 18, 2020. This is in line with the appearance of pollution in the winter of 2020. In France, the alpha variation is estimated to be approx. 40% more infections As the original strain, that is when the British believe Toxicity 50% More.

Due to the predominance of early 2021 and the many waves of pollution in France, it is now almost undetectable, often replaced by delta variation, which is highly contagious.

This is the name given to the first South African variant that caused concern in France in the spring of 2021. In February, the South African variant represented 55% of positive cases in the Moselle segment, or higher than the alpha variant. At the end of April, Olivier Véran panicked at the sudden increase in the circulation of this variant in Ile-de-France, where it went from 6% to 10% in a week.

One variant is considered to be of concern, as there is a risk of some escape from the effectiveness of the vaccine, especially the effectiveness of the astrogenic vaccine. On April 9, the French National Institutes of Health (HAS) recommended giving preference to messenger RNA vaccines (i.e., Pfizer and Moderna) in Moselle over Astrogeneka due to the significant presence of beta variants. According to the GISAID site, a variant that has almost disappeared from radar today is the last recorded case in France before October 12.

Read more

In South Africa, before the arrival of Omigran, beta was suppressed by the arrival of Delta, which, like all other types, including C.1.2, was briefly of concern.

Read more >> New Variation C.1.2: Should We Worry?

The gamma, also known as beta, also known as the Brazilian variant, caused particular concern in France in the spring of 2021. Recognized in France in early February, the gamma variant will be released in December 2020 in Manaus (Brazil).

The strongest variant in Guyana, also known as P1, is mild in metropolitan France, with about 10% of cases in the Grand Est region in the spring. This is worrying as many studies show a high prevalence of 40 to 120%. In addition, this variant has the potential to escape the immune response triggered by infection by other circulatory strains, thus increasing the risk of re-infection. This could explain its growth in the spring of 2021.

A variant that has gradually disappeared from radar in Europe. Therefore, in France, the last case registered by GISAID was before September 27th. However, it is more prevalent in Latin America, where cases were reported in November in Brazil, Ecuador, Argentina and Peru.

First diagnosed in India in December 2020, it is estimated by the British study to be 60% more contagious than the alpha variant, which is much more contagious than the original strain of SARS-Cov-2 in Europe.

In early summer, it took only 10 weeks for the majority in France to change, gradually changing to alpha and other varieties in circulation. The delta currently dominates the old continent and North America, and is responsible for the current wave of pollution affecting Europe.

Two “variations to follow”

Other categories are classified as variants to be monitored by the WHO, due to characteristics such as contagion, severity of the disease, immunodeficiency, ability to diagnose or treat the disease, and key community to spread.

First identified in Peru in December 2020, it was identified on June 15 in 29 countries. In France, the first case was diagnosed in May, which represented 0.2% of the test sequences analyzed in France on July 15.

According to the WHO, the lambda variant is “associated with significant rates of social outbreak in many countries, with increasing prevalence over time and increasing COVID-19 incidence”.

On June 14, 2021, the WHO classified this variant as a “must-see variant” due to its global expansion and numerous significant mutations. In competition with the delta variant, it failed to establish itself in Europe. In France, according to GISAID, the last case is before October 12. However, it is more prevalent in South America, but is declining.

The Mu variant, first identified in Colombia in January 2021, has been causing concern since the end of the summer. While its prevalence “steadily increased” in Colombia and Ecuador, the WHO classified it as a variant to watch in September, and is now responsible for 39% and 13% of infections, respectively.

In circulation in Latin America, it is less common in Europe. The case was registered in Europe only on November 2 last month in Spain. In France, it has not been detected since August 31, according to GISAID, the “victim” of competition from the delta, shown on this map in the evolution of variations in Colombia. In pink, the growth curve of the delta burns and crushes the muzzle in red.

“Depressed” types

These types of monitoring variations have been very widespread in the past, but many types have been downgraded to the “variations under surveillance” category. “Compared to other circulating variants of SARS-CoV-2, a variant or variant of anxiety that has been shown to pose a significant additional risk to global public health can be reclassified.” WHO explains.

This is the case with kappa varieties: p.1.617.1; Iota: p.1.526; Etta: P.1.525; Epsilon: P1.427 / P1.429, modified from variations to be followed under supervision. Others, Zeta: P.2; Theta: P.3. Not classified as a variant under observation.

Video – What you need to know about the Omicron variant