Thailand has detected its first known case of the latest Omicron sub-variant, BA.2.75, initially detected in India in June and now present in at least 15 countries, health authorities confirmed on Wednesday.
The sub-variant was found in a 53-year-old man in the southern province of Trang on June 28. His sample was sent to the Department of Medical Sciences for DNA sequencing, said the Centre for Medical Genomics (CMG) at Ramathibodi Hospital.
He had attended an international meeting in Phuket before developing Covid-19 symptoms and subsequently testing positive.
The case was recorded in GISAID, the world's Covid-19 database, on Monday as the first example of BA.2.75 in the kingdom.
As of Wednesday, 359 BA.2.75 cases have been recorded in GISAID, said Dr Supakit Sirilak, director-general of the Department of Medical Sciences.
The sub-variant is believed to be more capable of bypassing the immunity produced by existing Covid-19 vaccines and natural immunity acquired through infections than previous strains.
The first outbreak linked with BA.2.75 in India has almost come to an end, said the CMG. That is believed to be the result of the antibodies left by the huge BA.2 outbreak there. Thailand experienced a similar BA.2 outbreak.
Compared to BA.2, BA.2.75 has far more mutations, especially in its spike protein, Dr Supakit said, adding that while the G446S mutation helps the virus evade immunity, another called R493Q makes it more capable of binding well with human cells when entering the body and spreading to other people.
The WHO has listed it as a variant of concern and lineages under monitoring (VOC-LUM).