Maguari Virus Associated with Human Disease

Abstract

Despite the lack of evidence for symptomatic human infection with Maguari virus (MAGV), its close relation to Cache Valley virus (CVV), which does infect humans, remains a concern. We sequenced the complete genome of a MAGV-like isolate (OBS6657) obtained from a febrile patient in Pucallpa, Ucayali, Peru, in 1998. To facilitate its classification, we generated additional full-length sequences for the MAGV prototype strain, 3 additional MAGV-like isolates, and the closely related CVV (7 strains), Tlacotalpan (1 strain), Playas (3 strains), and Fort Sherman (1 strain) viruses. The OBS6657 isolate is similar to the MAGV prototype, whereas 2 of the other MAGV-like isolates are located on a distinct branch and most likely warrant classification as a separate virus species and 1 is, in fact, a misclassified CVV strain. Our findings provide clear evidence that MAGV can cause human disease.

Keywords: Argentina; Brazil; Cache Valley virus; Central America; Colombia; Ecuador; Fort Sherman virus; French Guiana; Maguari virus; Mexico; Panama; Paraguay; Peru; Playas virus; South America; Tlacotalpan virus; United States; arboviruses; bunyavirus; disease; human infection; mosquitoes; orthobunyavirus; phylogeny; vector-borne infections; viruses.

Figure 1

Geographic locations from which virus strains used in study of human infection with MAGV were isolated. Red star indicates the location of the MAGV-like isolate OBS6657; circles indicate source locations for other isolates used in this study. CVV, Cache Valley virus; FSV, Fort Sherman virus; MAGV, Maguari virus; PLAV, Playas virus; TLAV, Tlacotalpan virus.

Figure 2

Phylogenetic relationship of MAGV-like isolate OBS6657 to other MAGV and CVV isolates and reference orthobunyaviruses. Maximum-likelihood trees (Jones, Taylor, and Thornton model, gamma-distributed) were constructed on the basis of the amino acid sequences of the nucleoprotein (A), glycoprotein (B), and polymerase (C). Bootstrap values based on 1,000 replicates are indicated for values >60. Sequences generated in this study are shown in red bold. Human isolates within the CVV, MAGV, and Córdoba virus clades are underlined, and the OBS6657 isolate is indicated with a red star. Scale bars indicate nucleotide substitutions per site. CVV, Cache Valley virus; CODV, Córdoba virus; MAGV, Maguari virus.