Respiratory infections and coinfections: geographical and population patterns.

INTRODUCTION

Acute respiratory infections are the second cause of mortality in children younger than five years, with 150.7 million episodes per year. Human orthopneumovirus (hOPV) and metapneumovirus (hMPV) are the first and second causes of bronchiolitis; type 2 human orthorubulavirus (hORUV) has been associated with pneumonia in immunocompromised patients.

OBJECTIVE

To define hOPV, hMPV and hORUV geographical distribution and circulation patterns.

METHOD: An observational, prospective cross-sectional pilot study was carried out. Two-hundred viral strains obtained from pediatric patients were genotyped by endpoint reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

One-hundred and eighty-six positive samples were typed: 84 hOPV, 43 hMPV, two hORUV and 57 co-infection specimens. Geographical distribution was plotted. hMPV, hOPV, and hORUV cumulative incidences were 0.215, 0.42, and 0.01, respectively. Cumulative incidence of hMPV-hORUV and hMPV-hOPV coinfection was 0.015 and 0.23; for hOPV-hMPV-hORUV, 0.035; and for hORUV-hOPV, 0.005. The largest number of positive cases of circulating or co-circulating viruses occurred between January and March.

CONCLUSIONS

This study successfully identified circulation and geographical distribution patterns of the different viruses, as well as of viral co-infections.