Across 1990–2023, childhood respiratory infectious mortality — spanning 26 lower respiratory infection etiologies plus tuberculosis, COVID-19, and pertussis — totaled 965,330 deaths in 2023 (95% UI: 680,096–1,342,437). Shannon diversity rose 16.1%, and the effective number of causes nearly doubled from 5.57 to 9.94, inversely correlated with total deaths (Spearman ρ = −0.997). Whooping cough ranked second at 112,954 deaths, uniquely rebounding 111% after pandemic-era collapse. Nineteen of 29 causes exceeded an 80% geographic concentration threshold in sub-Saharan Africa and South Asia.
This preprint — not yet peer-reviewed and subject to revision — offers a rare integrated view of a mortality landscape that GBD has historically reported in fragmented modules. The central insight is counterintuitive: as total child deaths fall, the remaining burden spreads across more pathogens simultaneously, meaning single-vaccine or single-pathogen campaigns address an ever-shrinking fraction of the problem. The pertussis rebound is particularly alarming given known vaccine coverage gaps and raises questions about pandemic-era immunization disruption effects that persist well beyond COVID-19 itself. The finding that 19 of 29 causes are poverty-locked argues powerfully for horizontal platform interventions — oxygen access, antimicrobials, referral systems — rather than purely vertical pathogen-specific programs. Methodologically, summing GBD uncertainty intervals across modules risks compounding estimation error, a limitation warranting scrutiny in peer review. Still, the diversity-concentration paradox identified here is a clinically and policy-relevant framing that could meaningfully reshape global child health strategy.