The Impact of Low-Level Viraemia on Virological Failure-Results From a Multicenter HIV Antiretroviral Therapy Cohort Study in Yunnan, China.

Background: HIV viral load (VL) is an important indicator to monitor treatment response in antiretroviral therapy (ART). Patients on ART may experience viral blips, with low-level elevations of VL between 50 and 999 copies/mL known as low-level viraemia (LLV), but not reaching the threshold for virological failure (≥1,000 copies/mL) defined by WHO guidelines. The objective was to investigate the long-term impact of LLV on virological failure. Methods: We analyzed adults who were ART naïve at baseline. LLV was defined as having an VL of 51-999 copies/mL at least once. The subjects with LLV were grouped into three categories: 51-199, 200-399, and 400-999 copies/mL. Patients with multiple episodes of LLV were classified based on the highest VL result. The subjects with LLV were also grouped by the frequency of LLV, i.e., a single episode, two consecutive episodes, two intermittent episodes, more than two consecutive episodes, and more than two intermittent episodes. Multivariable Cox models were used to predict the association of LLV with virological failure. Results: A total of 93,944 subjects were included. The median number of VL tests performed was 3. There were 21,203 LLV cases, with an overall incidence of 22.6%. Most of the LLV cases were found in subjects with LVs of 50-199 copies/mL, followed by 400-999 and 200-399 copies/mL. Most of the LLV cases experienced single episodes, and the numbers of LLV with two consecutive episodes, two intermittent episodes, more than two consecutive episodes and more than two intermittent episodes were decreased successively. The risk factors associated with virological failure include: intermediate-level (200-399 copies/mL) and high-level (400-999 copies/mL) LLV, single episodes of LLV and two or more than two consecutive episodes of LLV, which may put the subjects at a 1.28-2.26-fold higher risk for virological failure. Conclusion: Strengthened immediate medical attention should be placed on patients with VL of 200-999 copies/mL. The patients having experienced LLV once should be targeted for case management and repeat VL testing within 24 weeks to determine persistent LLV and monitor virological failure.

Early Initiation of ARV During Pregnancy to Move towards Virtual Elimination of Mother-to-Child-Transmission of HIV-1 in Yunnan, China.

OBJECTIVE: To identify factors associated with mother-to-child-transmission and late access to prevention of maternal to child transmission (PMTCT) services among HIV-infected women; and risk factors for infant mortality among HIV-exposed infants in order to assess the feasibility of virtual elimination of vertical transmission and pediatric HIV in this setting. DESIGN: Observational study evaluating the impact of a provincial PMTCT program. METHODS: The intervention was implemented in 26 counties of Yunnan Province, China at municipal and tertiary health care settings. Log linear regression models with generalized estimating equations were used to identify unadjusted and adjusted correlates for late ARV intervention and MTCT. Cox proportional hazard models with robust sandwich estimation were applied to examine correlates of infant mortality. RESULTS: Mother-to-child- transmission rate of HIV was controlled to 2%, with late initiation of maternal ARV showing a strong association with vertical transmission and infant mortality. Risk factors for late initiation of maternal ARV were age, ethnicity, education, and having a husband not tested for HIV. Mortality rate among HIV-exposed infants was 2.9/100 person-years. In addition to late initiation of maternal ARV, ethnicity, low birth weight and preterm birth were associated with infant mortality. CONCLUSIONS: This PMTCT program in Yunnan achieved low rates of MTCT. However the infant mortality rate in this cohort of HIV-exposed children was almost three times the provincial rate. Virtual elimination of MTCT of HIV is an achievable goal in China, but more attention needs to be paid to HIV-free survival.

Prevention of mother-to-child transmission of HIV-1 using highly active antiretroviral therapy in rural Yunnan, China.

OBJECTIVE: To demonstrate that the use of highly active antiretroviral therapy (HAART) to interrupt transmission of HIV-1 from mother to baby is effective, safe, and feasible in a remote rural region of China. METHODS: Between November 2005 and May 2009, we enrolled 279 HIV-1-infected pregnant women to receive HAART to interrupt transmission of HIV-1 to their newborns across 16 counties in Yunnan. All women were started on triple combination therapy and submitted to regular blood draws to monitor CD4 T cells and viral load in their blood plasma. Infants received a single dose of nevirapine at birth and 1 or 4 weeks of zidovudine depending on the length of the mother's regimen. Exclusive formula feeding was recommended, and families were provided with 12-month supply of formula. Mothers and infant pairs were followed for 12-18 months postdelivery. RESULTS: Of 279 enrolled HIV-infected women, 222 (79.6%) were identified and started treatment by 28 weeks of pregnancy. Viral load was undetectable at time of delivery for 62.4% (136 of 218) at delivery, with a mean 1.76 log viral load reduction between enrollment and delivery. Two of 193 babies (1.0%) who have already been tested became infected with HIV-1. Seven of 223 babies have died. By Kaplan-Meier analysis, cumulative one-year survival was 96.3%. CONCLUSIONS: The project demonstrated that HAART for all infected pregnant women is effective with a vertical transmission rate of approximately 1%. Thus, this project provides a model for China to scale up its efforts to prevent mother-to-child transmission of HIV-1.