[Key clinical manifestations to differentiate Oropouche fever from dengue and other arboviral diseases: a living systematic reviewRevisão sistemática viva das manifestações clínicas da febre do Oropouche: características-chave para diferenciá-la da dengue e de outras arboviroses].

Objectives: To assess the frequency of symptoms in patients with Oropouche fever and compare them with those observed in patients with dengue and other arboviral diseases.

Methods: A systematic review was conducted following the MOOSE and PRISMA reporting guidelines. The review included studies on acute clinical manifestations in patients with Oropouche fever. Searches were conducted in PubMed, Virtual Health Library, Cochrane Library, and Google Scholar up to September 2024. The symptoms of Oropouche fever were compared to those of dengue and other arboviral diseases. Certainty of evidence was assessed using the GRADE approach.

Results: A total of 23 studies covering 3648 patients with Oropouche fever were included. The most frequent symptoms in patients with Oropouche virus infection were fever (97%) and headache (86%). There was no difference in frequency of fever or headache between patients with Oropouche and dengue. However, odynophagia (28%) and abdominal pain (15%) were more frequent in Oropouche than in dengue, with odds ratios (ORs) of 3.20 and 2.50, respectively. Myalgia (69%) and arthralgia (57%) were less frequent in Oropouche fever than in dengue.

Conclusions: Fever and headache are common in Oropouche virus infection, but do not help discriminate it from dengue. However, odynophagia and abdominal pain are more frequent in patients with Oropouche fever, while myalgia, arthralgia, and rash are more prevalent in dengue. These findings may aid in differential diagnosis in areas of arboviral co-circulation. Further studies on the recurrence and duration of symptoms are needed to improve diagnostic strategies.