The spectrum of disease severity, the burden of hospitalizations and associated risk factors in confirmed dengue among persons of all ages: findings from a population based longitudinal study from Barbados.

Background: Dengue can be severe and potentially fatal in a small proportion. Risk factors for severe dengue have been highlighted but long term population based study is lacking. We assesses the severity and hospitalization in dengue.Methods: This is a longitudinal population based prospective study of all persons with confirmed dengue in Barbados during the years 2006 through 2015. Most recent WHO criteria were used for classifying dengue severity. Disease severity and hospitalization need were two main outcomes.Results: There were 2939 ambulatory and 1234 hospitalized cases. Compared to those in the age group 16-60 years, the risk of hospitalization was higher among persons over 61 years (RR = 1.8) and those under 16 years (RR = 1.7). Overall, 190 (4.4%), 771 (17.8%) and 3202 (73.7%) were classified as severe and dengue with and without warning signs respectively. The risk of severe dengue was higher in the over 60 years age group compared to the 16-60 years (RR = 1.97). Primary infection was at a lower risk of severe dengue compared to secondary infection (RR = 0.46).Conclusions: Less than 5% of dengue presents with severe disease, the risk being highest among the elderly and those with previous dengue.