Dynamic Partnerships and HIV Transmissions by Stage.

Human Immunodeficiency Virus;Sexual Partnerships;Networks;Pair Approximation;Individual-based Model;Public Health;Health Sciences;Epidemiological Science

Kim, Jong-HoonWilson, Mark L. ;

University of Michigan

关键词: Human Immunodeficiency Virus;    Sexual Partnerships;    Networks;    Pair Approximation;    Individual-based Model;    Public Health;    Health Sciences;    Epidemiological Science;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/64804/jonghook_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Effectiveness of some control programs of human immunodeficiencyvirus (HIV) transmission depends on what proportion of newinfections are attributable to a particular stage of HIVinfection.Most model analyses for the transmission of HIV bystage have neglected real-world details such as sexualpartnerships, risk fluctuation and sexual role segregation. Toexamine the effects of those real-world details on thetransmission of HIV by stage, we constructed various models of HIVtransmission using both individual-based and deterministiccompartmental approaches.Transmissions through long-term sexual partnerships generate localnetwork structure in which infected individuals are connected tofewer susceptible partners compared with the population average.The increasing depletion of susceptible partners around infectedindividuals monotonically decreases basic reproductive ratio and endemic prevalence of HIV infection with increasingpartnership duration. The role of primary HIV infection (PHI),i.e., fractional contribution to basic reproductive ratio of PHI or the fraction oftransmissions from PHI at endemic phase, has a U-shapedrelationship with partnership duration.It drops in shorterpartnerships, but rises in longer partnerships. This pattern isdetermined by the difference in relative depletion of susceptiblepartners by stage of infection. As the risk of transmission ismade increasingly different by type of sex act while keeping thetotal population risk unchanged, endemic prevalence and the roleof PHI become smaller.The decreased role of PHI is only observedwhen partnerships are long lasting.If individuals fluctuatebetween high- and low-risk phases, susceptible individuals arereplenished from low- to high-risk phase and infection is spreadfrom high- to low-risk phase.This increases endemic prevalencein the overall population.Risk fluctuation also causesindividuals with PHI to be more likely to be in high-risk phase,which increases the role of PHI.Realistic details like sexual partnerships, sexual rolesegregation and risk fluctuation can strongly influence thetransmission of HIV and do so differentially by stage of HIVinfection.Model analyses intended to evaluate control programoptions or assess the role of a particular stage of infection needto take these details into account.