COMPARATIVE EVALUATION OF ELISA, PCR, AND NS1 ANTIGEN DETECTION FOR DENGUE VIRUS DIAGNOSIS

Abstract

Background: Dengue fever is a rapidly spreading mosquito-borne viral disease, posing a significant public health challenge in endemic regions like Pakistan. The disease presents with a range of clinical manifestations, from mild febrile illness to severe complications such as dengue hemorrhagic fever and dengue shock syndrome. Early and accurate diagnosis is essential for effective patient management and outbreak control. Molecular, antigen-based, and serological tests serve as primary diagnostic tools; however, their feasibility and accuracy in resource-limited settings remain areas of concern.

Objective: This study aimed to evaluate the diagnostic performance, feasibility, and cost-effectiveness of enzyme-linked immunosorbent assay (ELISA), non-structural protein 1 (NS1) antigen detection, and reverse transcription polymerase chain reaction (RT-PCR) for dengue virus detection at Chaudhry Muhammad Akram Teaching & Research Hospital, Lahore.

Methods: A cross-sectional study was conducted over six months at Chaudhry Muhammad Akram Teaching & Research Hospital. A total of 440 patients with suspected dengue fever were tested using NS1 antigen detection, IgM and IgG ELISA, and RT-PCR. Blood samples were collected, processed, and stored at -20°C. Statistical analysis was performed using SPSS software to assess the sensitivity, specificity, and diagnostic efficiency of each modality.

Results: The NS1 antigen was detected in 18 cases, primarily within the first week of illness, with platelet counts ranging from 50,000 to 150,000 cells/μL. IgM ELISA identified 44 recent infections, with platelet counts between 70,000 and 130,000 cells/μL. IgG ELISA confirmed 31 past or secondary infections, with platelet counts between 80,000 and 140,000 cells/μL. A total of 250 patients exhibited clinical symptoms suggestive of dengue but tested negative in laboratory evaluations. Additionally, 97 patients had inconclusive results.

Conclusion: This study highlights the importance of combining NS1 antigen detection, ELISA, and RT-PCR in a structured diagnostic approach for effective dengue management. Improving diagnostic capacity in resource-limited settings can enhance patient outcomes and strengthen public health surveillance.