title: Summary of human infection with highly pathogenic avian influenza A (H5N1) virus reported to WHO, January 2003-March 2009: cluster-associated cases.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D006801:Humans; D007223:Infant; D053124:Influenza A Virus, H5N1 Subtype; D007251:Influenza, Human / Q000453:epidemiology* / Q000401:mortality; D008875:Middle Aged; D012111:Residence Characteristics; D012621:Seasons; D013997:Time Factors; D014944:World Health Organization; D055815:Young Adult