Growth scaling for the early dynamics of HIV/AIDS epidemics in Brazil and the influence of socio-demographic factors

Publication date: 7 April 2018 Source:Journal of Theoretical Biology, Volume 442 Author(s): L. Dinh, G. Chowell, R. Rothenberg The early dynamics of an infectious disease outbreak can be affected by various factors including the transmission mode of the disease and host-specific factors. While recent works have highlighted the presence of sub-exponential growth patterns during the early phase of epidemics, empirical studies examining the contribution of different factors to early epidemic growth dynamics are lacking. Here we aim to characterize and explain the early incidence growth patterns of local HIV/AIDS epidemics in Brazil as a function of socio-demographic factors. For this purpose, we accessed annual AIDS incidence series and state-level socio-demographic variables from publicly available databases. To characterize the early growth dynamics of the HIV/AIDS epidemic, we employed the generalized-growth model to estimate with quantified uncertainty the scaling of growth parameter (p) which captures growth patterns ranging from constant incidence ( p = 0 ) to sub-exponential (0 < p < 1) and exponential growth dynamics ( p = 1 ) at three spatial scales: national, regional, and state levels. We evaluated the relationship between socio-demographic variables and epidemic growth patterns across 27 Brazilian states using mixed-effect regression analyses. We found wide variation in the early dynamics of the AIDS epidemic in Brazil, displaying sub-expon...
Source: Journal of Theoretical Biology - Category: Biology Source Type: research