First outbreak of Oropouche Fever reported in a non-endemic central-western region of the Peruvian Amazon. Molecular diagnosis and clinical characteristics

Abstract

Background: Oropouche virus (OROV) is an underreported and emerging infectious disease. Its incidence is underestimated mainly due to clinical similarities with other diseases that are also caused by arboviruses present in endemic areas. We report the first outbreak of OROV in the western region of the Peruvian Amazon in the department of Huanuco, Peru. Methods & Materials: Transversal studie about a outbreak occurred in the region of Huanuco, Peru during July of 2016. Blood samples were taken from 268 patients who presented acute febrile syndrome to be later analyzed for Oropouche Virus via Polymerase Chain Reaction. Results: Of all 268 patients, 46 (17%) cases tested were positive for OROV. the most common symptom reported was headaches with a frequency of 87% (n = 40) followed by myalgias with 76% (n = 35), arthralgias with 65.2% (n = 30), retro-ocular pain 60.8% (n = 28) and hyporexia with 50% (n = 23). Concerning signs and symptoms that may suggest severe OROV infection, 4.3% (n = 2) had low platelet count, 8.6% (n = 4) had intense abdominal pain, and only 2.1% (n = 1) had a presentation with thoracic pain. Conclusion: The disease caused by the OROV is an emerging, underdiagnosed infection that requires ongoing research to determine its virulence, pathogenesis, host range and vectors involved in the urban and sylvatic cycles as well as identifying new genotypes to implement diagnostic tools with appropriate sensitivity, that can be applied to endemic regions. This study reports an outbreak of OROV in a region where it was not previously identified. Even though there have not been any mortalities reported since the initial identification of OROV, recent outbreaks demonstrate a pattern that highlights the emerging potential of the virus and shows the need to prioritize local epidemiological surveillance and the implementation of new public health policies to decrease the health implications that future outbreaks may cause in the population.