As quoted in ProMED:

Regarding recent outbreaks of human metapneumovirus infection in Saskatchewan, a large number of prevalence surveys have been published for newer respiratory tract viruses in Canada. The following are abstracted from the GIDEON Database

Human metapneumovirus (HMPV)
4.1 percent of adults with community-acquired pneumonia (2005 publication)
9.5 percent of respiratory specimens from the community and 25 percent of outbreaks - median age 24 months (Calgary, 2007 publication)
14.8 percent of patients with acute respiratory tract infection (4 provinces, 2001 to 2002 influenza season)
8 percent of acute lower respiratory tract infections (Montreal, 2001)
3.9 percent of pediatric inpatients and outpatients (Alberta, 2002 to 2003)
6 percent of children below age 3 years hospitalized for acute respiratory tract infections (Quebec, 2001 to 2002)
4 percent of adults hospitalized with community-acquired pneumonia (Edmonton, 2008 publication)
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