Discipline: Mathematics and Statistics
Jesus Vega - Universidad del Sagrado Corazon
Co-Author(s): James Humberstone, Science, Technology and Innovation Institute, Francisco Gavidia University, El Salvador Gabriel Morey-Leon, National Institute of Public Health Research "Leopoldo Izquieta Pérez", Guayaquil, Ecuador
Hypothesis: Human Immunodeficiency Virus (HIV-1) is a major pandemic with approximately 36.7 million people infected worldwide. Although the prevalence of HIV-1 in Latin America remains stable (around 0.5%) [UNAIDS, 2016], the epidemic is globally expanding among Men Seeking Men (MSM), independently of country or gross domestic product [Beyrer, 2010]. One of the major current public health challenges for HIV includes providing effective HIV antiretroviral therapy to affected populations centered on the relationship between access and adherence to treatment and prevalence of drug resistance. We aim to study the effect of delay treatment among MSM in Ecuador where is expected to observe a reduction of resistant cases but an increase on the infected population. Methods: A mathematical model that incorporates a non-exponentially distributed infectious period and variable treatment coverage is developed and analyzed numerically to capture the HIV transmission dynamics in Ecuador. Results: (i)The introduction of early treatment (infection stage 1 and 2) prevents HIV to become large outbreak but considerably increases drug resistant cases, (ii) treatment on late stages (stage 3 and 4) has the opposite effect (increases infected population and reduce the resistant population), (iii) even under our proposed optimal conditions (i.e. high treatment coverage and efficacy with low level of transmissibility) any treatment strategy will be ineffective if there is no decrease on risky behavior of the individuals, (iv) from the global uncertainty and sensitivity analysis, it was observed that the rate of transmissibility and treatment effectiveness have significant influence on the model’s prediction. Conclusion: The introduction of delay treatment allows a faster spreading of the virus among MSM due to their risky behavior but maintain a small resistant population. For the next part of the project will consider other high risk populations, like prostitutes and drug addicts, in the model. Include variable adherence and common mutations (resistance) to study the best line of treatment.
Funder Acknowledgement(s): National Science Foundation (DMS1263374); Office of the President of ASU; Office of the Provost at ASU.
Faculty Advisor: Emmanuel Morales-Butler, firstname.lastname@example.org
Role: I was in charge of the mathematical part of the project which includes the formulation of the model and the analytical analysis.