Human metapneumovirus infection: An emerging problem in high-risk infants

Abstract

Viral infection is an important cause of upper and lower respiratory tract illness in infants and young children world wide, causing significant respiratory morbidity in affected children. Premature infants, especially those with bronchopulmonary dysplasia (BPD), chronic oxygen dependency and congenital heart disease are regarded as “high risk” infants because a higher proportion of such infants require hospitalization and admission to the pediatric intensive care units. Their problems often continue after discharge from hospital, as they may develop persistent symptoms such as cough and wheeze. This has significant impact on resource utilization, cost of care and quality of life for the infants and their families. A number of viruses such as respiratory syncytial virus (RSV) and adenoviruses are well recognized to be implicated in the pathogenesis of serious lower respiratory tract illness, but in a substantial number of symptomatic children, no virus can be identified. This may be due to a variety of reasons including insensitivity of the specific diagnostic tests at individual hospitals, or the medical profession’s unawareness of newly emerging pathogens. This was indeed the case when researchers in the Netherlands isolated human metapneumovirus (hMPV) from children for the first time in 2001 [1]. Since then, investigations in different coun-