UK: Delta with K417N – the “mountaineers” variant – PHE #coronavirus Delta-AY.1 update

B.1.617, B.1.617.2, Canada, Coronavirus, D614G, Delta, Delta-AY.1, England, Germany, Health, India, Infection, Japan, K417N, L452R, Mutation, Nepal, P681R, Poland, Portugal, Russia, Science, Scotland, Singapore, Switzerland, T478K, Testing, Transmission, Turkey, UK, USA

Of the 36 cases of Delta-AY.1 (mountaineers) variant, 27 cases were known to have a vaccination status within the National Immunisation Management System (NIMS). 

“Through routine scanning of variation in Delta a small number of sequences were detected which had acquired the spike protein mutation K417N. Information suggests that there are at least 2 separate clades of Delta with K417N. One clade is large and internationally distributed with PANGO lineage designation AY.1. A second clade found in sequences uploaded to GISAID from the USA. There is limited epidemiological information available at present.

International Epidemiology
As of 7 June 2021, 63 genomes of Delta with K417N have been identified on GISAID. from Canada (1) Germany (1), Russia (1), Nepal (2), Switzerland (4), India (6), Poland (9), Portugal (12), Japan (13), USA (14).

There are currently 36 cases of Delta-AY.1 in England (35 confirmed sequencing and 1 probable genotyping) plus an additional 10 sequences which include some cases in other UK nations and some genomes for which case data is being sought. The first 5 cases were sequenced on 26 April 2021 and were contacts of travellers to Nepal and Turkey. All these cases were detected in the West Midlands. Cases have been detected in 6 different regions in England (Table 21, Figure 26). The majority of cases are in younger individuals, with 2 cases of age 60 or over (Figure 27). Out of the 36 cases, there were 11 travel associated cases (6 travellers and 5 cases amongst contacts of travellers). Twelve cases have no history of travel or contact with travellers. Countries of travel included red-list countries (Nepal and Turkey), amber-list countries (Malaysia) and green-list countries (Singapore).

Of the 36 cases, 27 cases were known to have a vaccination status within the National Immunisation Management System (NIMS), when linked on NHS number. Of these, 18 cases occurred in people who were not vaccinated, 2 cases in people who had received their first dose within 21 days of specimen date, 5 cases in people who had received their  first dose more than 21 days after specimen date. There was a total of 2 cases where there were more than 14 days between the second dose of vaccine and a positive specimen. No deaths have been recorded amongst the 36 cases.”

PHE download – SARS-CoV-2 variants of concern and variants under investigation in England  – Technical briefing 15 (PDF)


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