Dengue-COVID-19 overlap: A single-center prospective observational study in a tertiary care setting in India

Abstract

Background: Dengue-COVID-19 overlap is a mixture of both diseases sharing few similarities in pulmonary and extrapulmonary involvement. Although dengue fever is more commonly reported in tropical settings, very little literature is available regarding dengue-COVID-19 overlap in Indian context. Due to high prevalence of both diseases later being pandemic disease, and overlapping laboratory and clinical parameters, we have conducted a study to observe dengue-COVID-19 overlap in Indian settings in tertiary care hospitals. Methods: This prospective, observational study included 600 COVID-19 cases with dengue nonstructural protein 1 or dengue immunoglobulin (Ig) M positive, with lung involvement documented and categorized on high-resolution computerized tomography (CT) thorax at entry point. All cases were subjected to dengue IgG antibody titers and dengue IgM/IgG antibody titer analysis after 12 weeks of discharge from the hospital. Results: Dengue-COVID-19 overlap was documented in 16.33% (98/600) of cases. CT severity has documented a significant correlation with dengue-COVID-19 overlap cases (P < 0.00001). Hematological evaluation, white blood cell count, and platelet count were having a significant association with dengue-COVID-19 overlap (P < 0.0076 and P < 0.00001, respectively). Clinical parameters as hypoxia have a significant association with dengue-COVID-19 overlap (P < 0.00001). Inflammatory markers such as interleukin-6, C-reactive protein, and lactate dehydrogenase have a significant association in dengue-COVID-19 overlap (P < 0.00001), respectively. In study of 600 cases of “dengue COVID 19 overlap”, post COVID lung fibrosis was documented in 92/600 cases. Serological assessment between dengue IgM/IgG antibody and COVID antibody titers has a significant association with post covid lung fibrosis (P < 0.00001). Conclusions: Dengue-COVID-19 overlap is clinical syndrome with overlapping clinical and laboratory workup of both the illnesses. High index of suspicion is must in all COVID cases in tropical settings where dengue is endemic, and all cases with leucopenia and thrombocytopenia with fever should be screened for dengue serology. False-positive dengue serology or dengue antigen cross-reactivity is known to occur in underlying COVID-19 illness, and have impact on clinical outcome as it will result in delay in COVID appropriate treatment initiation and many cases require intensive care unit treatment due to progressed COVID pneumonia.