Epidemiological Dynamics and Trends of Dengue Outbreaks in São Tomé and Príncipe: A Comprehensive Retrospective Analysis (2022-2024)

Dengue remains a significant public health issue globally, particularly in tropical and subtropical regions. This study analyzes the demographic and environmental factors influencing dengue transmission in São Tomé and Príncipe from 2022 to 2024. Employing a retrospective design combined with mixed methods, we investigated dengue trends in São Tomé and Príncipe. Data on dengue cases, age distribution, environmental factors (temperature, rainfall, and wind speed), and recovery time were collected from official records. Descriptive statistics were used to analyze the demographics of dengue cases, while correlation and regression analyses, along with spatial analysis, examined the relationships between environmental factors and dengue incidence. The highest incidence of dengue occurred in adolescents and young adults, with 10–19 years accounting for the largest share of cases. Dengue transmission was strongly correlated with rainfall, peaking during months with significant precipitation (May to July). The correlation between temperature and dengue cases was weaker, indicating that while temperature influences mosquito activity, rainfall is the primary driver of transmission. Recovery times varied, with a mean of 6.81 days. A dramatic spike in dengue cases in 2022 accounted for 91.9% of total cases over the three-year period, while 2023 and 2024 saw sharp declines in incidence, corresponding with reduced rainfall. The findings highlight the critical role of rainfall in dengue transmission, reinforcing the need for timely vector control measures, especially during periods of heavy precipitation. The age distribution of cases suggests targeted interventions for younger populations.