Objective  To examine general situation and change trend of low-level viraemia (LLV) among human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) patients under antiviral therapy (ART) in Yunnan province and to provide evidences to further relevant studies.

  Methods  From the Data and Information Management System for Integrated HIV/AIDS Prevention and Control of Chinese Center for Disease Control and Prevention, we extracted demographical, clinical and viral load (VL) detection data on all HIV/AIDS patients receiving ART at the age of more than 15 years in Yunnan province during the period from 2004 through 2018. The incidence of LLV among the HIV/AIDS patients with different ART regimens was analyzed statistically.

  Results  Of the 93 944 HIV/AIDS patients included in the study, 21 203 (22.6%) were detected with LLV. Among the patients with LLV, 25% were detected with LLV at least two times; the most detected LLV level was 51 – 199 copies/mL, followed by 400 – 999 and 200 – 399 copies/mL; the once-only LLV was detected most frequently and the detection frequency decreased in turn for successive two times, discontinuous two times, successive several times, and discontinuous several times; the detected incidence of LLV was the highest during the first year of ART and the incidence declined yearly after the initiation of ART. During the retrospective observation period among the 76 736 HIV/AIDS patients receiving first-line ART, the detected frequency of 51 – 199 and 200 – 399 copies/mL LLV increased first, with the highest frequency in 2010, then declined, with the lowest frequency in 2016, and increased again; the detected frequency of 400 – 999 copies/mL LLV and virologic failure (VF) of ≥ 1 000 copies/mL decreased yearly before 2012 and then remained at a stable level. While among the 17 208 HIV/AIDS patients receiving second-line ART, the detected frequencies of the four levels of LLV mentioned above varied similarly, with a decreasing trend between 2008 – 2012 and a stabilization later after.

  Conclusion  The detected incidence of LLV is relatively high among HIV/AIDS patients with different ART regimen in Yunnan province. The effect of LLV on outcomes of ART needs to be explored.