Dengue Epidemic during COVID-19 Pandemic: Clinical and Molecular Characterization – A Study from Western Rajasthan

Abstract

The concurrent emergence of dengue fever and the COVID-19 pandemic posed significant challenges to India’s healthcare system, particularly in Western Rajasthan, a region characterized by its arid climate and unique socio-demographic conditions. This study aimed to investigate the clinical and molecular characteristics of dengue during the COVID-19 pandemic, focusing on trends, diagnostic challenges, and serotype distribution.

Conducted at Dr. S.N. Medical College, Jodhpur, in 2021, the study included 550 dengue-positive patients confirmed via rapid diagnostic tests and further analyzed using Dengue NS1 antigen and IgM antibody ELISA. Molecular characterization was performed using RT-PCR for serotyping.

The results revealed a male predominance (72.36%) and a higher incidence in the 21–30-year age group (39.09%). Urban areas accounted for 67.73% of cases, with significant NS1 and IgM positivity (p = 0.042 and p = 0.004, respectively). Most cases (86.91%) were managed outpatient, though IgM positivity was significantly higher among hospitalized patients (19.19%, p < 0.001), indicating severe or prolonged infections. Platelet counts were above 100,000/mm³ in 86.91% of cases, with only 0.37% showing critically low counts (< 20,000/mm³). Seasonal analysis showed a peak in October (n = 325), correlating with post-monsoon vector breeding. Serotyping identified DENV2 as the dominant strain (97.42%), associated with severe dengue manifestations, including Dengue Haemorrhagic Fever (DHF).

The study highlights the dual burden of dengue and COVID-19, emphasizing the need for enhanced vector control, improved diagnostic strategies and public health interventions during overlapping outbreaks. The predominance of DENV2 underscores the importance of serotype-specific surveillance and preparedness to mitigate future dengue epidemics in the region.