Human parvovirus B19 genotype 1 in suspected dengue patients of Tefé, Amazonas State, Brazil.

Human parvovirus B19 (B19V) is a common pathogen, which on infection causes variety of clinical conditions from benign self-limiting exanthematous disease and other similar pathologies to fetal death.We collected 341 serum samples between the first and fourth day after the onset of symptoms from all patients suspected of dengue fever who were attended at Regional Hospital of Tefé. Initially, patients were screened for malaria by blood smear test and negative samples were sent to Fundação de Medicina Tropical Doutor Heitor Vieira Dourado (FMT-HVD) situated in Manaus (AM) for dengue testing using semi-nested multiplex PCR. Further, we investigated 44 malaria and dengue-negative samples of children for B19V DNA by nested-PCR. Positive samples were analyzed by BLAST against entire public non-redundant nucleotide database and genotyped by phylogenetic analyses using neighbor-joining clustering method.Eight samples (18.2%) were found to be PCR positive. Fever, headache, ocular pain, and/or muscle pain were reported as the most frequent symptoms by the patients and none were diagnosed with rash at the time of sample collection. Phylogenetic analysis of major capsid protein 2 (VP2) and VP3 coding region showed high similarity with B19V genotype 1.Our results reveal the spread of B19V genotype 1 in Tefé. Moreover, our results emphasize the significance of laboratorial differential diagnosis using molecular techniques in patients with acute febrile, and thereby aid the health surveillance system in improving patient care even in the remote areas of Amazon.