Definition: In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
Input: The human metapneumovirus (hMPV) is a newly described member of the Paramyxoviridae family belonging to the Metapneumovirus genus. Since its initial description in 2001, hMPV has been reported in most parts of the world and isolated from the respiratory tract of subjects from all age groups. Despite the fact that prospective and case-control studies have been limited, the epidemiology and clinical manifestations associated with hMPV have been found to be reminiscent of those of the human respiratory syncytial virus, with most severe respiratory tract infections occurring in infants, elderly subjects, and immunocompromised hosts. Additional research is needed to define the pathogenesis of this viral infection and the host's specific immune response. Acute respiratory tract infections (ARTIs) are a major cause of morbidity and mortality worldwide. A variety of viruses, including the influenza viruses, human respiratory syncytial virus (hRSV), parainfluenza viruses, adenoviruses, rhinoviruses, and coronaviruses, have been associated with clinical syndromes ranging from mild illnesses, such as the common cold, to more severe devastating conditions, such as pneumonia. However, ∼50% of the cases of community-acquired pneumonia in adults and 15%-35% of cases of bronchiolitis and pneumonia in pediatric patients are still without a known etiology [1-3]. Along with inadequate diagnostic methods, this observation also suggests that other respiratory tract infectious agents may exist and remain to be identified. A new respiratory virus, the human metapneumovirus (hMPV) was first isolated in 2001 from nasopharyngeal aspirates (NPAs) obtained from young children in The Netherlands [4] . On the basis of morphological, biochemical, and genetic features, hMPV was tentatively classified with avian metapneumovirus (APV), the causative agent of an upper respiratory tract disease in turkeys and other birds [5], in the Metapneumovirus genus. The latter, together with the Pneumovirus genus (containing hRSV as the type species), is Note added in proof. Human metapneumovirus was recently isolated from previously virus-negative nasal wash specimens from 49 (20%) of 248 young children consulting at the Vanderbilt Clinic (Nashville, TN) for lower respiratory tract illnesses [44] . Extrapolation of these results to the entire cohort of patients observed at this institution over a 25-year period (1976-2001) suggests that the prevalence of human metapneumovirus infection was ∼12% in all outpatient children with lower respiratory tract diseases.

Human Metapneumovirus: A New Player among Respiratory Viruses