It is one of the special observations. The Indian variant of the SARS Cov-2 coronavirus (B.1.617), recently designated by the World Health Organization (WHO) as a variant of concern (VOC), has over 4,500 viral sequences uploaded to the Gisaid database from 44 countries of the world – including Italy – and the WHO has received reports of surveys from 5 other countries. For this variant which was first reported in India in October 2020, three sub-lineages have been identified that differ “in a few but potentially relevant mutations in the Spike protein and in the prevalence of detection globally,” points out. ‘WHO. At present, WHO has classified it as a variant of concern based on the first available data which appear to show higher transmission rates. Among other things, signs of rapid increases in prevalence have been observed in multiple countries. Furthermore, preliminary evidence suggests a “potential reduction in efficacy of the anti-Covid monoclonal antibody bamlanivimab”, and a “potentially slightly reduced susceptibility to neutralizing antibodies (limited evidence is available on this for a single sub-lineage). of the Indian variant on the efficacy of vaccines or therapies, or on the risks of reinfection, remain uncertain. Raising questions about the role of variant B.1.617 and others such as the English one in circulation, was the resurgence of Covid in India. recent risk assessment, carried out for this country by the WHO, found that the resumption and the surge of Covid transmission in India is based on several potential factors, including the increase in the share of cases of potentially increased transmissibility variants. India and the United Kingdom have reported the largest number of cases sequenced for this variant no designated sub-lineage B.1.617.2 as a variant of concern at national level, evaluating it “at least equivalent in terms of transmissibility” to the English variant and pointing out, however, that the data are insufficient to evaluate the potential for immune escape. As of 5 May, the UK was reporting 520 genomically confirmed cases of B.1.617.2 (of which around two thirds nationally acquired), 261 confirmed B.1.617 cases (with no further delineation of sub-lineages) and 9 confirmed B cases .1.617.3. Further studies are urgently needed, highlights the WHO to clarify the uncertain aspects. There are currently preliminary analyzes of the viral sequences available which suggest that the sub-lineages B.1.617.1 and B.1.617.2 of the Indian variant have a substantially higher growth rate than other variants circulating in India. Then, preliminary laboratory studies awaiting peer review suggest a “limited reduction” of neutralization by antibodies. One study finds “a 7-fold reduction” in the neutralization efficacy against variant B.1.617.1 by antibodies generated by vaccination with Moderna and Pfizer / BioNTech. Second work confirms a reduction for Pfizer / BioNTech. A third examines a limited sample of convalescent sera and another vaccine and concludes that most of the neutralizing activity has been retained. A fourth study talks about a 3-fold reduction for Pfizer and a 2-fold reduction in sera for patients recovered from severe disease.