The impact of respiratory infections in BRICS+ countries: trends, causes, and risk factors—a longitudinal study

The BRICS+ countries now encompass nearly half of the global population, yet the burden of lower respiratory infections (LRI) in this region remains largely unquantified. Employing robust age-period-cohort models on data sourced from the Global Burden of Disease Study (GBD) 2019, we systematically quantify the temporal patterns, underlying causes, and risk determinants of LRI within the BRICS+ cohort over nearly three decades (1990–2019). However, no studies have systematically assessed the disease burden caused by LRI in these countries. Using data from the Global Burden of Disease Study (GBD) 2019 and age-period-cohort models, we estimate the temporal patterns, causes, and risk determinants of LRI burden between 1990 and 2019. The findings showed between 1990 and 2019, BRICS+ countries faced a staggering total of 256,821,260 LRI events, reflecting more than half (52.5%) of the global incidence and a significant toll on public health, with LRI responsible for 34.2% of all related global deaths in 2019. Local drift showed that the improvement was most pronounced in children. In terms of numbers, pneumococci are the common LRI type in all countries. In terms of risk factors, our analysis reveals marked heterogeneity in risk factors across BRICS+ nations, highlighting the necessity for tailored public health strategies. The result shows that the observed decline in LRI burden concomitant with increasing socio-developmental indices suggests that collaborative health initiatives and knowledge sharing within the BRICS framework could markedly enhance public health outcomes for lower respiratory infections across the developing world.