In this work, a co-infection model for human papillomavirus (HPV) and Chlamydia trachomatis with cost-effectiveness optimal control analysis is developed and analyzed. The disease-free equilibrium of the co-infection model is shown not to be globally asymptotically stable, when the associated reproduction number is less unity. It is proven that the model undergoes the phenomenon of backward bifurcation when the associated reproduction number is less than unity. It is also shown that HPV re-infection ( $$\varepsilon_{\textsc{p}} \ne 0$$ ε P ≠ 0 ) induced the phenomenon of backward bifurcation. Numerical simulations of the optimal control model showed that: (i) focusing on HPV intervention strategy alone (HPV prevention and screening), in the absence of C. trachomatis control, leads to a positive population level impact on the total number of individuals singly infected with C. trachomatis , (ii) Concentrating on C. trachomatis intervention controls alone ( C. trachomatis prevention and treatment), in the absence of HPV intervention strategies, a positive population level impact is observed on the total number of individuals singly infected with HPV. Moreover, the strategy that combines and implements HPV and C. trachomatis prevention controls is the most cost-effective of all the control strategies in combating the co-infections of HPV and C. trachomatis .

中文翻译：

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HPV-沙眼衣原体联合感染模型的最佳控制和成本效益分析

在这项工作中，开发和分析了具有成本效益最佳控制分析的人乳头瘤病毒 (HPV) 和沙眼衣原体的共感染模型。当相关的繁殖数不太统一时，共感染模型的无病平衡显示不是全局渐近稳定的。证明当相关的再生数小于1时，该模型出现后向分叉现象。还表明HPV再感染（$$\varepsilon_{\textsc{p}} \ne 0$$ ε P ≠ 0 ）诱导了后向分叉现象。最优控制模型的数值模拟表明：（i）仅关注HPV干预策略（HPV预防和筛查），在没有沙眼衣原体控制的情况下，导致对单独感染沙眼衣原体的总人数产生积极的人口水平影响，(ii) 在没有 HPV 干预策略的情况下，仅专注于沙眼衣原体干预控制（沙眼衣原体预防和治疗），一个积极的影响观察到对单独感染 HPV 的个体总数的人口水平影响。此外，结合并实施 HPV 和沙眼衣原体预防控制的策略是所有控制策略中在对抗 HPV 和沙眼衣原体合并感染方面最具成本效益的策略。观察到对单独感染 HPV 的个体总数有积极的人口水平影响。此外，结合并实施 HPV 和沙眼衣原体预防控制的策略是所有控制策略中在对抗 HPV 和沙眼衣原体合并感染方面最具成本效益的策略。观察到对单独感染 HPV 的个体总数有积极的人口水平影响。此外，结合并实施 HPV 和沙眼衣原体预防控制的策略是所有控制策略中在对抗 HPV 和沙眼衣原体合并感染方面最具成本效益的策略。