Clinical manifestations of primary and secondary dengue in Paraguay and its relation to virus serotype

Introduction: Dengue virus (DENV) infection is currently a major cause of morbidity in the world, and its incidence has mainly increased during the last years in Latin America, including Paraguay. The objective of this study was to compare the clinical and laboratory findings of dengue and assess whether the serotype is a risk factor for severity. Methodology: We included patients <= 15 years old hospitalized with dengue at the Institute of Tropical Medicine, from Paraguay, from 2007 to 2018. Patients were classified according to the 2009 WHO dengue classification guidelines and were stratified by serotype into three groups according to the hospitalization period: the 2007 epidemic (DENV-3), the 2012-2013 epidemic (DENV-2) and the 2016-2018 epidemic (DENV-1). Results: Of 784 children hospitalized for dengue, 50 cases (6.3%) were caused by DENV-3, 471 (60%) by DENV-2, and 263 (33.5%) by DENV-1. Myalgias and headache were associated with DENV-3 cases and abdominal pain was associated with DENV-2 cases. Bleeding was observed mainly in DENV-1 and 2 cases. Patients with DENV-2 infections experienced more severe disease, required fluid expansion more frequently, and exhibited more often shock and admission in the ICU. Secondary cases of dengue were more severe that primary cases. Patients with infection by DENV-2 had longer hospital stays (5.1 +/- 2.8 days) when compared to DENV-3 o DENV-1 infection cases (2.9 +/- 1.6 days and 4.36 +/- 2.7 days, respectively) (p < 0.05). Conclusions: The DENV serotype has a profound impact on the clinical manifestations and severity of dengue. DENV-2 infections were associated more frequently to requirement of fluid expansion, shock, and longer hospital stay.