The variant omicron is already predominant at least in Madrid and the Canary Islands, where it supposed, respectively, 55.4% and 54.8% of cases in the week from December 13 to 19.
This reflects the last update of the epidemiological situation of the SARS-COV-2 variants in Spain published by the Ministry of Health.
According to the report, the percentage of contagions associated with the omicron variant in the aforementioned week throughout the country is only 20.5%, although this figure “could infrastruct the intensity of the circulation of this variant at the present time.”
Current data “are not totally representative at the national level since, even though the samples are randomly carried out, the absence of data from some communities (especially in the latest weeks) and the different proportion in which each contributes
One of them, limit the interpretation of this information, “recognizes the document.
In general, the information available from sequencing and Screening by PCR, “indicates that a rapid substitution of the DELTA variant is being produced by omicron,” says the document.
“Given the rapidity with which this expansion is taking place, the delay in obtaining and communication of the results means that the values reflected in the weeks included in the report can infrastruct the intensity of the circulation of this variant at the present time”
.
The rhythm of omicron growth is being “very fast”, find health technicians in the report.
“We already have data two or three weeks for several communities, which allows us to appreciate a very rapid growth trend. Considering the set of samples analyzed at the national level, the percentage of samples compatible with omicron was multiplied by 10 between the week
48 and 49, “they point out.
“In Spain, it has been very quickly from detecting the first cases associated with travelers from South Africa to detect cases linked to Community transmission and to verify rapid growth in sequencing-based surveillance systems and randomized PCR of random samples”, continues
The document, which also emphasizes that “the data is still very scarce to determine the true impact of the omicron variant in the epidemiological characteristics of the infection, but the preliminary studies point to greater transmissibility and a greater immune escape.
Level of uncertainty regarding possible changes in the severity of cases. ”
In the last 4 weeks analyzed by health (from mid-November to mid-December) only 35 of 2127 sequenced random samples correspond to lineages different from those of Delta and ÓMicron variants.
According to estimates of the World Health Organization (WHO), the omicron variant has already been detected in 110 countries and continues to spread exponentially, “doubling its cases in the communities where it is transmitted in a matter of two or three days.”
Although it is still not clear what the profile of this variant is, the preliminary data show that it has a great capacity for transmission and reinfection, although it seems also having a lower capacity than its predecessors to cause serious illness.
South Africa was, on November 25, the first country to give the voice of alarm about this new variant that accumulates many more mutations than any of the ‘previous’ versions of the SARS-COV-2.
If compared to the first Wuhan viruses, ÓMICRON has 55 changes in its genome, 32 of them in the S protein, the key that employs the pathogen to enter the cells (15 of these mutations are precisely in the binding domain
to the receiver).
Some of these mutations – such as N501 and T95i, T478K or G142D- are old-known;
They were already present in variants such as alpha, beta or gamma and have been associated with greater transmissibility or with greater ease to evade the immune response.
