This is the first comprehensive molecular epidemiological study of HIV-1 CRF01_AE in Hong Kong. It revealed that MSM contact is becoming a major route of local CRF01_AE transmission in Hong Kong. Epidemiological linkage of CRF01_AE between Hong Kong and China observed in this study indicates the importance of regular molecular epidemiological surveillance for the HIV-1 epidemic in our region.

Abacavir hypersensitivity is associated with the presence of human leukocyte antigen (HLA)-allele B*5701. However, the cost and workload of routine HLA-B*5701 pretreatment screening is relatively heavy. This study aimed to determine the prevalence of the HLA-B*5701 allele in the HIV-positive population under care in Hong Kong. Blood samples from 1264 HIV-1 infected patients in Hong Kong were collected between 2007 and 2011 for this study. HLA-B*5701 screening of the study group was determined by in-house polymerase chain reaction (PCR) followed by confirmation using the AlleleSEQR(®) HLA-B PCR/Sequencing Kit (Celera Corporation for Abbott, San Francisco, USA). HLA-B*5701 carriers were identified among 3% of Caucasians, 1% of non-Chinese Asians and 0.5% of Han-Chinese in Hong Kong. Our findings revealed that HLA-B*5701 pretreatment screening might not be necessary for the local Han-Chinese population due to its low prevalence.