Economic Burden of Inappropriate Antibiotic Prescribing Attributable to Dengue in Singapore.

BACKGROUND: Dengue has a clinical presentation similar to that of bacterial infections, creating diagnostic uncertainty that may lead to inappropriate antibiotic prescribing. OBJECTIVE: To estimate the magnitude of inappropriate antibiotic prescribing attributable to dengue in Singapore and assess the associated economic burden from healthcare system and societal perspectives over the period 2015-2024. METHODS: A decision tree model was developed to determine costs associated with 142,525 laboratory-confirmed dengue cases reported in Singapore during 2015-2024. National surveillance data and prescribing rates informed model inputs. Costs were estimated from healthcare system and societal perspectives and expressed in 2025 Singapore dollars (SGD). Deterministic and probabilistic sensitivity analyses were conducted. RESULTS: The model estimated 7055 antibiotic prescriptions, of which 6866 were inappropriate; 79.6% of inappropriate prescriptions occurred in ambulatory care. The cumulative burden associated with the 2015-2024 caseload was SGD 14.32 million from the healthcare system perspective and SGD 16.13 million from the societal perspective. Prolonged hospitalisation was the largest cost component followed by adverse drug events due to antibiotic use. In the probabilistic analysis, the mean societal burden was SGD 16.16 million, with a 95% uncertainty interval of SGD 2.78-49.60 million. CONCLUSIONS: In this analysis, inappropriate antibiotic prescribing attributable to dengue was associated with an estimated cumulative economic burden of SGD 14.32 million from the healthcare system perspective and SGD 16.13 million from the societal perspective in Singapore during 2015-2024, expressed in 2025 values. Direct medical costs accounted for most of the burden, and the findings support further evaluation of approaches to reduce unnecessary prescribing.