Human Bocavirus 2 in Children, South Korea

of invasive pneumococcal infections in children among 8 children's hospitals in the United States after the introduction of the 7-valent pneumococcal conjugate vaccine .dence of pneumococcal disease due to non-pneumococcal conjugate vaccine (PCV7) serotypes in the United States during the Effect of community-wide conjugate pneumococcal vaccine use in infancy on nasopharyngeal carriage through 3 years of age: a cross-sectional study in a high-risk population. To the Editor: In 2009, Kapoor et al. and Arthur et al. published reports on the prevalence of the newly identified parvovirus, human bo-cavirus 2 (HBoV-2), in fecal samples (1,2). HBoV-1 had been discovered in 2005 (3), and reports indicate its possible role in respiratory diseases such as upper respiratory tract infections , lower respiratory tract infections (LRTIs), and in exacerbation of asthma (4); in these diseases, the virus co-infects with other respiratory viruses (5). Systemic infection with HBoV-1 and possible association of this virus with other diseases such as gastroenteritis, Kawasaki disease, and hepatitis have been reported (6–8). We looked for HBoV-2 in clinical samples from children with various diseases, including acute LRTIs, Ka-wasaki disease, Henoch-Schönlein purpura, and hepatitis. During September 2008–January 2009, a total of 212 nasopharyngeal aspirates were collected from 212 children (median age 8 months, range 1–59 months) hospitalized with acute LRTIs at Sanggyepaik Hospital in Seoul, South Korea. Previously, during January 2002–June 2006, a total of 173 serum samples had been obtained from children (age range 1 month–15 years) with hepatitis (hepatitis B, 20 samples; hepatitis C, 11 samples; unknown hepatitis, 31 samples), Ka-wasaki disease (12 samples), and He-noch-Schönlein purpura (18 samples) and from healthy children (same age range, 81 samples) (9). The study was approved by the internal review board of Sanggyepaik Hospital. DNA was extracted from serum samples, and RNA and DNA were extracted from nasopharyngeal aspirates by using a QIAamp Viral RNA Mini Kit (QIAGEN, Hilden, Germa-ny) and a QIAamp DNA Blood Mini Kit (QIAGEN GmbH), respectively. All nasopharyngeal aspirates were tested by PCR for common respiratory viruses such as respiratory syncy-tial virus, influenza viruses A and B, parainfluenza virus, and adenovirus, as described previously (10). PCRs to detect HBoV-1 were performed by using primers for the nonstructural (NS) 1 and nucleocapsid protein (NP) 1 genes, as described previously (10). Additional PCRs for rhinovirus, human metapneumovirus, human coro-navirus (hCoV)-NL63, hCoV-OC43, hCoV-229E, hCoV HKU-1, WU poly-omavirus, and KU polyomavirus were performed, as described, for HBoV-2 –positive samples (10). HBoV-2 …