To understand the epidemiological characteristics of adult human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) patients who have not received antiretroviral therapy (ART) in Jilin Province.

A total of 830 HIV/AIDS patients who had not received ART and were cumulatively reported in Jilin Province from 2004 to 2025 in the China Disease Prevention and Control Information System were selected. The patients were divided into two groups based on the year of diagnosis: 2004—2015 and 2016—2025. The χ² test was used for intergroup comparison and stratified analysis.

Among the 830 untreated patients, males accounted for 84.6%. The age groups of 45-59 years and ≥60 years accounted for 33.9% and 34.0%, respectively. Those with junior high school education or below accounted for 63.4%.Unmarried individuals accounted for 68.3%. Homemakers, unemployed, and those waiting for employment accounted for 42.2%.The main transmission routes were homosexual transmission (48.2%) and heterosexual transmission (45.3%). Testing among other patients accounted for 42.0%, while testing and counseling accounted for 25.3%. The proportion of patients with a first CD4⁺T lymphocyte count <200 cells/μl was 62.5%. Compared with the 2004—2015 group, the 2016—2025 group showed increases in the proportions of individuals aged 25-44 years, those with college education or above, unmarried individuals,homosexual transmission cases, and cases identified through testing and counseling. Cross-analysis of age and transmission route showed that homosexual transmission accounted for 58.3% in the <25-year-old group and 63.4% in the 25-44-year-old group. In the 45-59-year-old group, heterosexual transmission accounted for 50.2%. In the ≥60-year-old group, heterosexual transmission accounted for 51.1% (χ²=50.583, P<0.001). Stratified analysis by CD4⁺T level showed that the proportions of patients with CD4⁺T <200 cells/μl in the ≥60-year-old group (67.4%) and the 45-59-year-old group (66.2%) were significantly higher than the proportion in the <25-year-old group (20.8%) (χ²=39.320, P<0.001). Regarding transmission routes, the proportion of CD4⁺T <200 cells/μl in the homosexual transmission group (66.5%) showed no statistically significant difference from that in the heterosexual transmission group (60.1%) (χ²=11.092, P=0.086). Stratified by sample source, the highest proportion of CD4⁺T <200 cells/μl was found in the group tested among other patients (77.9%), while the proportion in the testing and counseling group was 54.3% (χ²=83.910, P<0.001).

The untreated HIV/AIDS patients in Jilin Province were predominantly middle-aged and elderly, with low educational levels and late diagnosis. However, the proportions of young and middle-aged adults, those with high educational levels, and those infected through homosexual transmission have increased in recent years. Two distinct subgroups exist within the untreated population: the middle-aged and elderly group,predominantly infected through heterosexual transmission and with more severe immune damage, and the young and middle-aged group, predominantly infected through homosexual transmission. Differentiated intervention strategies are needed for the two groups to increase the proportion receiving treatment.