A case series of suspected dengue-like illness in Pakistan

Dengue is an arbovirus endemic to Pakistan, with frequent outbreaks reported nationwide. We report a case series of 11 patients who presented during an outbreak of dengue-like illness in Karachi between November and December 2021. Although initial dengue testing was negative in most patients, further molecular testing identified Zika virus in two patients, including one patient with dengue and Zika virus co-infection. Neither patient had a recent travel history; however, absence of travel history alone does not establish local transmission. This case series highlights the diagnostic challenge of distinguishing Zika virus and dengue virus infection in patients presenting with dengue-like illness and supports consideration of broader molecular testing during unexplained arboviral outbreaks. Keywords: Arboviruses, Coinfection, Dengue, Outbreaks, Zika virus.