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

Abstract

Introduction: Oropouche fever is an under-reported and emerging infectious disease caused by Oropouche virus (OROV). Its incidence is under-estimated mainly due to clinical similarities with other endemic arboviral diseases and the lack of specific diagnostic tests. We report the first outbreak of Oropouche fever in a western region of the Peruvian Amazon in Huanuco, Peru. Methods: A transversal study was carried out during an outbreak in the western Region of Huanuco, Peru between January and July of 2016. Blood samples of 268 patients with acute febrile syndrome were collected and analyzed for OROV via RT-PCR and genetic sequencing. Results: Of all 268 patients, 46 (17%) cases tested positive for OROV. The most common symptoms reported were headache with a frequency of 87% (n = 40) followed by myalgia with 76% (n = 35), arthralgia with 65.2% (n = 30), retro-ocular pain 60.8% (n = 28) and hyporexia with 50% (n = 23). Some patients showed a clinical presentation suggestive of severe OROV infection, of which 4.3% (n = 2) had low platelet count, 8.6% (n = 4) had intense abdominal pain, and 2.1% (n = 1) had a presentation with thoracic pain. Conclusion: This study reports an outbreak of OROV in a region where this virus was not previously identified. The disease caused by OROV is an emerging, underdiagnosed infection that requires further 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 sensitive and specific diagnostic tools that can be applied to endemic regions.

Oropouche infection a neglected arbovirus in patients with acute febrile illness from the Peruvian coast

“…Amplification by PCR assay for the detection of OROV was carried out using the primers described by Moreli et al [14], and PCR conditions described by Silva-Caso et al [9].…”

“…In Peru situation is similar, studies have reported the presence of the four serotypes of DENV in the Peruvian coast, being the serotype DENV 2 the most frequent during the period from May to August (i.e., in 2016), as well as the Zika virus (ZIKV) and the Chikungunya virus (CHIKV) [7]. In the last 3 years, the presence of the Oropouche virus (OROV) has been reported, reemerging in some areas such as Madre de Dios or recently appearing in other areas such as Huánuco [8,9]. Our study describes the presence of OROV, an emerging pathogenic arbovirus in the north coast of Peru and its main clinical characteristics.…”

Unidentified dengue serotypes in DENV positive samples and detection of other pathogens responsible for an acute febrile illness outbreak 2016 in Cajamarca, Peru

“…In Peru, the increasing prevalence of DENV has caused different outbreaks, reaching up to 35,000 confirmed cases per year, and largely affecting the southern region of Cajamarca [ 12 ]. However, in recent years other emerging viral pathogens have gained attention due to their increasing detection in Peru and Latin America, such as Zika, Chikungunya and Oropuche virus, with epidemiological implications still unknown in our population [ 4 , 7 , 13 ].…”

A Silent Public Health Threat: Emergence of Mayaro Virus and Co-infection with Dengue in Peru

“…However, Semliki group alphaviruses have been implicated in causing arthralgias [15] and persistent incapacitating joint pain due to MAYV infection has been previously reported in a series of imported cases [16][17][18]. Accurate clinical differentiation between arbovirus and MAYV is a challenge for clinicians in endemic areas [21]; however, without sensitive and speci c diagnostic tools, a precise etiological diagnosis cannot be easily achieved [14,22].…”