An Alarmingly High Proportion of HIV-1 Isolates Carrying Mutations Corresponding to Resistance to Antiretroviral Drugs among HIV-Positive High-Risk Groups in Central Vietnam: a Substudy of the National Sentinel Survey.

We studied the prevalence of HIV drug resistance among high-risk groups such as injecting drug users (IDUs), female sex workers (FSWs), and men having sex with men (MSM) in central Vietnam. We used HIV-positive blood samples from 2012-2013 sentinel surveillance surveys. Study subjects were screened for HIV infection by standardized screening assays, and the HIV-positive samples were further tested for HIV viral load and drug-resistance mutations (DRMs) by in-house assays. DRMs were identified using the Stanford University online sequence analysis tool. Their risk behaviors were also investigated. During the study period, 6,016 (high-risk) subjects were screened, and 97 tested positive for HIV infection (IDUs: n = 63, 3.0%; FSWs: n = 24, 0.9%; and MSM: n = 10, 1.0%). Ninety-two of the 97 samples (45 from 2012 and 47 from 2013) were available for further testing. HIV RNA was detected in 56 (60.9%) of the 92 samples, and drug resistance genotyping was successfully performed on 40 (71.4%) samples. All these isolates were subtype CRF01_AE, except for 1 (2.5%) IDU whose HIV belongs to subtype B. Thirteen individuals (32.5%) were carrying HIV with at least 1 DRM: 9 IDUs, 1 FSW, and 3 MSM. Thus, HIV seroprevalence among high-risk individuals in central Vietnam is low, but a high proportion of drug resistant HIV-1 isolates is observed in the high-risk group.

Antibiotic residue monitoring results for pork, chicken, and beef samples in Vietnam in 2012-2013.

A monitoring plan of residual antibiotics in food of animal origin was conducted in Vietnam from 2012 to 2013. Meat samples were collected from slaughterhouses and retail stores in Ho Chi Minh City and Nha Trang. A total of 28 antibiotics were analyzed using a LC-MS/MS screening method. Sulfonamides, fluoroquinolones, and tilmicosin were detected in some of the samples. Sulfaclozine and fluoroquinolones were mainly detected in chicken samples, and sulfamethazine was mainly detected in pork samples. High levels of sulfonamide residues, ranging between 2500 and 2700 µg/kg sulfaclozine and between 1300 and 3600 µg/kg sulfamethazine, were present in two chicken and three pork samples, respectively. Tilmicosin was detected at ranges of 150-450 µg/kg in 10 chicken samples. Positive percentages were 17.3, 8.8, and 7.4% for chicken, pork, and beef, respectively, for an average of 11.9%. The results suggest an appropriate withdrawal period after drug administration had not been observed in some livestock.