Acute respiratory infection by human metapneumovirus in children in southern Brazil.
BACKGROUND
Human metapneumovirus (hMPV) has been described as an etiologic agent of acute respiratory infections (ARI), mainly in pediatric patients. Viral isolation is difficult and has low sensitivity, and consequently RT-PCR assays are currently used for detection.


OBJECTIVE
Detect hMPV in ARI in hospitalized children in Southern Brazil; standardize a RT-PCR for routine hMPV diagnosis; validate a positive control for molecular tests; and perform phylogenetics analyses.


METHODS
Nasopharyngeal aspirates (NPA) from 156 hospitalized children were studied. A conserved region of the nucleoprotein gene was cloned, characterized and used to standardize an RT-PCR assay. Phylogenetic analyses were performed. Clinical data were obtained from medical records.


RESULTS
hMPV was detected in 6.4% of the samples. Dyspnea and wheezing were frequently reported symptoms and the most common diagnoses were bronchiolitis, acute respiratory insufficiency or laryngotracheobronchitis. Nucleotide sequence alignment revealed 97.7% identity with genotype A1 of hMPV. The detection limit of hMPV genomes by RT-PCR in clinical samples was 180 copies/microL.


CONCLUSIONS
This is the first report of the detection and genetic characterization of hMPV infections in children with lower ARI in Southern Brazil.
do Carmo Debur
Maria
M
Laboratório de Virologia, Hospital de Clínicas da Universidade Federal do Paraná, Brazil.
Bordignon
Juliano
J
Duarte dos Santos
Claudia Nunes
CN
Vidal
Luine Rosele
LR
Nogueira
Meri Bordignon
MB
de Almeida
Sérgio Monteiro
SM
Raboni
Sonia Mara
SM
D000208:Acute Disease; D001938:Brazil; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D029121:Metapneumovirus / Q000235:genetics / Q000302:isolation & purification*; D009305:Nasopharynx / Q000821:virology; D018184:Paramyxoviridae Infections / Q000821:virology*; D010802:Phylogeny; D015203:Reproducibility of Results; D012141:Respiratory Tract Infections / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*