Detection of chikungunya infection in a dengue-endemic region: A case report of NS1-negative patient managed initially as dengue

This case report examines the diagnostic challenges in distinguishing chikungunya fever from dengue fever in a 25-year-old male living in a dengue-endemic area. This patient presented with high-grade fever, severe arthralgia, and myalgia, exhibiting symptoms which are common to both diseases. At the initial stage, despite being negative for dengue nonstructural protein 1(NS1) antigen test, the patient was managed as having dengue fever. However, the persistence of symptoms led to additional testing, and the results of chikungunya-specific polymerase chain reaction (PCR) testing became positive, confirming the diagnosis of chikungunya virus infection. The patient was subsequently managed for chikungunya. This case emphasizes the significance of maintaining a heightened suspicion for chikungunya, especially in instances with negative dengue NS1 antigen tests.