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Objective: To document infection with HIV type 1 (HIV-1) group M non-B subtypes in individuals living in New York City. Design: From October 1999 through April 2003, HIV-1-seropositive individuals were selected from 3 clinics in New York City based on having risk factors for infection with HIV-1 non-B subtypes. Methods: HIV-1 RNA was extracted from plasma samples, and partial gag, pol, or env genes were amplified by PCR analysis. The infecting HIV- 1 group M subtype was determined based on results of either heteroduplex mobility assay or sequencing and phylogenetic analysis. Results: Ninety-seven subjects were enrolled in the study. Of the 97 subjects, 91 (94%) were selected based on having emigrated from a non-European country, while 6 (6%) were native United States citizens. Subtypes were successfully determined in 53 (55%) of the 97 plasma samples tested. The subtypes in 2 plasma samples were unclassifiable. HIV-1 infections were classified as those due to the following group M subtypes: A (n = 4; 7%), B (n = 12; 22%), C (n = 8; 15%), F (n = 2; 4%), CRF01―AE-like (n = 7; 13%), CRF02―AG-like (n = 19; 34%), an intersubtype recombinant form G gag /A env (n = 1; 2%), and unclassifiable viruses (n = 2; 4%). Conclusion: This study reveals infection with a broad variety of HIV-1 group M subtypes mostly in the immigrant population of New York City as well as how several non-B subtypes are being introduced into the United States.

Objective: To investigate the genetic diversity of the HIV-1 circulating in Shanghai and to analyze the mutations in the protease (PR) gene associated with resistance to protease inhibitors (PIs). Design: The genetic diversity of HIV-1 and PI resistance–associated mutations was studied in 40 Shanghai HIV-1-seropositive treatment-naive residents. The patients studied were exposed to the infection mainly through contaminated blood products (hemophiliacs) (n = 17) and sexual contacts (n = 19). Samples from 2 injecting drug users (IDUs) and 2 children born to HIV-1 infected mothers were also analyzed. Methods: HIV-1 partial gag pol and env genes in infected plasma samples were amplified by reverse transcriptase polymerase chain reaction sequenced and phylogenetically analyzed. Analysis of PI resistance –associated amino acid substitution in PR was performed. Results: HIV-1 genes in 38 of the 40 plasma samples were successfully amplified and analyzed. Polymerase chain reaction amplification was successful for 16/17 hemophilia patients and 18/19 sexually infected individuals. While all the 16 hemophilia patients infected through contaminated blood products were infected with subtype B’ the 18 patients infected through sexual contact were infected with several subtypes including subtype A (n = 2) B (n = 4) B’ (n = 1) C (n = 2) CRF08_BC (n = 1) CRF01_AE (n = 7) and intersubtype recombinant CRF01_AE/B (n = 1). The 2 IDUs were infected with CRF08_BC and the 2 children born to HIV-1 infected mothers were infected with subtype B’ and CRF01_AE. PI resistance–associated amino acid substitutions were found at 1 codon in primary and 7 codons in secondary regions of the PR gene. Amino acid substitutions were more frequently found in the B/B’ sequences (69%) than in the non-B sequences (31%). Substitutions characteristic with the subtype B/B’ sequences mainly among hemophiliacs included L63P (87%) A71V/T (27%) and V77I (93%) while those that characterized the non-B sequences mainly found among heterosexuals included M36I (69%) and K20R (19%). Conclusion: This study reveals the presence of multiple HIV-1 subtypes and recombinants infecting Shanghai residents. The broad HIV-1 diversity is being introduced into this city through heterosexual contacts. This study also reveals that viruses infecting these treatment- naive patients have acquired both primary or secondary mutations in their PR genes. These studies should provide the basis for further epidemiologic surveys of HIV-1 subtypes and set strategies for treatment intervention and vaccine programs. (authors)