Surveillance of transmitted HIV type 1 drug resistance in newly diagnosed hiv type 1-infected patients in Shandong Province, China.

A survey to measure transmitted HIV-1 drug resistance (DR) was conducted in 2006 following the World Health Organization threshold survey protocol. Dried blood spots (DBS) were prepared from 53 newly HIV-1-diagnosed patients. Protease and reverse transcriptase (RT) gene regions were sequenced using a broadly sensitive genotyping assay and analyses to identify DR mutations and determine phylogeny of the HIV-1 strains were conducted. Forty-six of the 47 successfully genotyped DBS had no transmitted DR mutations; one had an NNRTI mutation (K101E) in the RT region. Phylogenetic analyses revealed 21 (44.7%) were CRF01_AE, 9 (19.1%) B, 6 (12.8%) CRF07_BC, 3 (6.4%) each of CRF08_BC and C, and 2 (4.3%) B/C unique recombinant forms (URF). The remaining three were one each of A/B, A/C, and unclassifiable. Our analyses indicate that the prevalence of transmitted DR in this population is low and the HIV-1 epidemic in the area was characterized by multiple subtypes and recombinant forms.