Prevalence of human coronaviruses in adults with acute respiratory tract infections in Beijing, China

Abstract

Human coronaviruses (HCoVs) are a common etiological agent of acute respiratory tract infections. HCoV infections, especially those caused by the two HCoVs identified most recently, NL63 and HKU-1, have not been characterized fully. To evaluate the prevalence and clinical presentations of HKU1 and NL63 in adults with acute respiratory tract infections, an investigation of HCoV infections in Beijing, China from 2005 to 2009 was performed by using reverse transcriptase PCR assays and sequencing analysis. Among 8,396 respiratory specimens studied, 87 (1%) clinical samples were positive for HCoVs, of which 50 samples (0.6% of the total) were positive for HCoV-OC43, 15 (0.2%) for HCoV-229E, 14 (0.2%) for HCoV-HKU1, and 8 (0.1%) for HCoV-NL63. The prevalence of HCoV infection in adults exhibited distinct seasonal fluctuations during the study period. In addition, patients positive for HCoV-229E infections were more likely to be co-infected with other respiratory viruses. Enterovirus, rhinovirus, and parainfluenza virus type 3 were the most common viruses found in patients with HCoV infections. The demographic and clinical data present in this study of HCoV infections in adults with acute respiratory tract infections should improve our understanding of the pathogenesis of HCoVs.

Figure 1

Number and detection rate of human coronavirus positive respiratory samples during the study period. The bar graph indicates the number of OC43, 229E, NL63, and HKU1 positive cases, and the line graph indicates the total detection rate of human coronavirus in each month.

Figure 2

Phylogenetic analysis of human coronavirus based on the partial sequence of the gene ORF 1ab. Phylogenetic trees were constructed based on nucleotide sequences of PCR products corresponding to the partial pol gene of OC43, 229E, NL63, and HKU1, analyzed by MEGA4.0 software using the distance method and the neighbor‐joining algorithm with Kimura 2 parameters. Each strain from this study is indicated by a specific identification code (PUMCH) followed by the patient number and GenBank accession number. The GenBank accession numbers of the reference sequences of OC43, 229E, NL63, HKU1A and B were NC005147, NC002645, NC005831, NC006577, and AY884001, respectively. Scale bar indicates nucleotide substitutions per site.