The fifth Kraken case in Spain was announced by Madrid's Gregorio Marañón Hospital. / SUR

Concerns over new Covid-19 subvariant Kraken in Spain

Catalonia, the Basque Country and Madrid have recorded infections with the highly transmissible XBB1.5 strain

ÁLVARO SOTO/RAQUEL MERINO

A fifth case of the Covid-19 subvariant XBB1.5, known as Kraken, has been recorded in Spain. This - the first in the region of Madrid - was announced on Monday 9 January by the Microbiology and Infectious Diseases Service of the Gregorio Marañón Hospital. The infected person is a 63-year-old man who is recovering well after having flu symptoms last week, and has not required hospital admission.

In recent days, Catalonia and the Basque Country have also recorded several cases of the strain, a highly transmissible variant first detected in the USA.

According to the latest data from the US Centers for Disease Control and Prevention, this subvariant accounts for nearly 41 per cent of new confirmed cases in the USA, and in the northeastern states, the percentage rises to 75 per cent.

Recently, the World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus noted that the international health agency "is closely monitoring and assessing the risk of this sub-variant and will report accordingly".

Kraken is a new mutation of Omicron, the most contagious Covid-19 variant to date, and comes from another variant, XBB, first detected in October, which is itself a recombination of two other Omicron subvariants.

Like the previous variants, Kraken, or XBB.1.5 is notable for its high infectious capacity. The WHO director general said he was "really concerned" about the current epidemiological picture of Covid-19, "both because of intense transmission in several parts of the world and because of a rapidly spreading recombinant subvariant", in reference to Kraken.

Kraken has been detected in 25 countries around the world, according to the WHO. The European Center for Disease Prevention and Control (ECDC) has identified infections in thirteen countries of the European Union, including Spain.

According to the first, preliminary, ECDC investigations, XBB.1.5 has the second highest transmission capacity of all the virus variants, only behind the original omicron, which in just one month, December 2021, became dominant around the world.

ECDC said XBB.1.5 has "a high level of immune escape" and "a transmissibility advantage", that is, vaccines lose effectiveness against the variant.