A theoretical model for the natural course of HIV infection in infants

HIV infection in young children differs markedly from that in adults: (i) children have higher viral loads (VL), (ii) their set point VL is not much lower than the peak VL, and (iii) children tend to progress faster towards AIDS. We use classic simple ODE models for HIV infection to study which differences between adults and children can explain these observations. We test whether (1) increased viral replication rates, (2) increased target cell population, (3) increased production of target cell population, and/or (4) delayed/weakened immune responses in children can explain the data. Whenever possible, we feed the model with parameter estimates from untreated paediatric data available from datasets within the EPIICAL project (https://www.epiical.org/). This data allowed us to reject hypothesis (1): the viral replication rate seems to be decreased in infants compared to adults. Thus, a mathematical model might help to get a better understanding of paediatric HIV infections and provides a foundation to simulate current cure and prevention strategies.