The so-called ‘California strain’ has registered 28 cases in Spain and contains a problematic mutation.
In the race for SARS-CoV-2 mutation infamy, it is the Indian variant that is grabbing all the headlines, given the situation in the country. However, the data offered by others tests the positive evolution of the pandemic and the efficacy of current vaccines.
Among them is the variant B.1.429, known as ‘Californian’ because that is where it was detected, in May 2020, although its presence increased between September and January 2021 from 0 to 50% of total cases. In Spain, according to the Ministry of Health, there are 28 cases, most with no known relationship to travel of any kind.
The call for attention on this variant has been given by an article published in the prestigious scientific journal Cell, where it is warned that the antibodies generated as a defense in people who have already had Covid-19 or who have been vaccinated against it are notably lower compared to infection by ‘classic’ variants.
A more infectious mutation
The authors of the work, who come from the University of California and various research institutions present in the area, sequenced a total of 2,172 genomes of the virus. 21.5% of them carried this variant, characterized by three mutations in protein S, which binds to human cells to infect them. One of them, L452R, also showed that it has a greater capacity for infection than the classic protein.
Next, they compared the Californian variant to 21 plasma samples from people who had had the disease when B.1.429 was not present or who had been vaccinated with the Pfizer-BioNTech or Moderna preparations.
Compared with the infection by classic variants (USA-WA1/2020 and D614G, the predominant ones before the analyzed one broke out), the Californian generated 6.7 fewer antibodies in convalescent plasma samples, and 2 times fewer antibodies in that of vaccinated people, which is qualified by the researchers as a “moderate resistance to neutralization by antibodies”.
“These findings indicate that the B.1.427/B.1.429 variant (the two branches of the Californian strain, although testing was done on B.1.429) warrants close monitoring and further investigation into its potential to cause future waves of disease. cases of Covid-19, accumulate future mutations and/reduce the effectiveness of vaccines”, they conclude.
Related to the Indian variant
The latest epidemiological report of the World Health Organization maintains the consideration of the Californian variant as ‘of interest’, the previous step to being ‘of concern’, a group in which there are only three strains: the British, the South African and the Brazilian.
This definition implies that it has been identified as the cause of community transmission or has been detected in multiple countries, which makes it essential to monitor its expansion.
The document dedicates a special section to the Indian variant (B.1.617), detected in October of last year, which it claims to have a greater contagion capacity.
Both this and the Californian share the dreaded L425R mutation, “which has been associated with increased transmissibility, reduced neutralization by some (but not all) monoclonal antibody treatments, and moderate reduction in post-vaccination serum neutralization in the United States.”
The 28 cases reported in Spain (although the number is low, in general, in Europe) of the Californian variant make it the main suspect among those considered of interest that have been reported in our country. Only the Nigerian (B.1.525) is, with 41 cases, ahead of her American cousin.