Objective  A mathematical model is proposed to analyze the dynamic evolution trend of the basic reproduction number of HIV/AIDS epidemics in Fujian province, to predict the infection scale of HIV/AIDS epidemics, and to provide evidence for HIV/AIDS prevention and control strategies.

Methods  A susceptible-infected-diagnosed-monitored-AIDS mathematical model is established to describe the transmission dynamics of HIV/AIDS within the local population. The next generation matrix method is used to calculate the basic reproduction number. The least squares method is applied to perform the parameter estimation and optimal fitting against the 2004-2022 surveillance data of Fujian province.

Results  The SIDMA model demonstrates a good fit and shows high consistency with the surveillance data. The basic reproduction number of HIV/AIDS epidemics in Fujian province shows a declining trend from 2004 to 2022, decreasing from 3.98 to 1.55. The tendency predictions under the baseline scenario indicates that the cumulative incidence of Fujian HIV/AIDS epidemics is 86.18/100 000. Among the intervention scenarios, scenario 1 decreases the cumulative incidence to 67.24/100 000, which is significantly better than the scenarios that only expands the HIV detection in scenario 3 or only reduces the exposure risk in scenario 5, where the cumulative incidences are 77.48/100 000 and 72.83/100 000, respectively. The prevention and control efforts are weakened in scenario 2, scenario 4 and scenario 6, leading to the cumulative incidences rising to 102.84/100 000, 97.46/100 000 and 91.40/100 000, respectively, which significantly enhances the prevalence risk of HIV/AIDS.

Conclusion  The transmission risk of HIV/AIDS epidemics in Fujian province shows a downward trend, and increasing detection rate and reducing effective contact rate are key measures to control the infection scale of HIV/AIDS epidemics. It is vital to continuously improve HIV detection strategies, to strengthen the preventive measures, to promote the transformation of HIV detection from passive to active, and to enhance the public willingness for receiving HIV detection as well as the accessibility of detection services.