Identification of HIV type 2 subtype B transmission in East Asia.

We isolated an HIV-2 strain (01JP-IMCJ/KR020) from a Korean patient who has lived in Japan for the past 6 years. He was infected with HIV-2 through heterosexual contacts in either Korea or Japan. The phylogenetic analyses based on the near full-length nucleotide sequence revealed that 01JP-IMCJ/KR020 belongs to HIV-2 subtype B cluster with high bootstrap support. This isolate harbors a 13-nucleotide insertion upstream of the NF-KB site, which is one of the sequence signatures specific to HIV-2 subtype B. This represents the first report of HIV-2 subtype B transmission in East Asia; three cases of HIV-2 subtype A infection have been reported in Korea in 1991-1998. This suggests that at least sporadic transmission of HIV-2, including both subtypes A and B, occurs in East Asia. It is necessary to keep monitoring HIV-2 to see whether there is an increasing trend toward HIV-2 infection in this particular area in Asia.