ABSTRACT
Objective@#To investigate the molecular evolution characteristics of human coronavirus (HCoV) subtypes in patients with fever and respiratory tract infection in Guangzhou from 2010 to 2012.@*Methods@#Partial fragments of NP, RdRp and S genes of HCoV-OC43, HCoV-229E and HCoV-NL63 positive samples were amplified by RT-PCR and sequencing. Bioinformatics software, including Bio-edit, Mega4.0 and Clustal1.83 were used for comparison and analysis of NP, RDRp and S gene sequences. Molecular evolutionary tree of different gene regions of HCoV-OC43, HCoV-229E and HCoV-NL63 were built.@*Results@#No remarkable variation or recombinant strain of HCoV-OC43, HCoV-229E and HCoV-NL63 was found in Guangzhou during 2010—2012. The HCoV-OC43 substrains were genetically closest to the strains found in Belgium and Hong Kong (GenBank accession number JN129834 and AY903460). HCoV-229E substrains were genetically closest to those found in Amsterdam (GenBank accession number JX503060) and HCoV-NL63 most genetically close to those in Amsterdam and Beijing (GenBank accession number JX104161 and DQ445911). The NP and RDRp genes of all subtypes were highly conserved, while S gene was more variable.@*Conclusions@#There were at least 3 substrains of HCoV-OC43, HCoV-229E and HCoV-NL63 epidemic in Guangzhou during 2010—2012, and no remarkable variation or recombinant viral strain was found. The NP and RDRp genes of all subtypes were highly conserved and can be used in virus detection, while S gene was more variable and suitable for phylogenetic and variation study.
ABSTRACT
Objective To sequence and analyze the complete genome of two human coronavirus NL63 (HCoV-NL63) strains collected from Beijing Children Hospital .Methods Eighteen pairs of primers were designed according to the gene sequences of HCoV-NL63 reference strain ( HCoV-NL63_Amsterdam 1) and used to amplify the target fragments covering the complete genome of HCoV-NL63 strains.Rapid ampli-fication of cDNA ends ( RACE) and RT-PCR assays were used to amplify the full length genome of HCoV-NL63 strains.Phylogenetic analysis was conducted by using Mega 5.0 software.Results The complete ge-nome sequences of the two HCoV-NL63 strains were 27 538 bp in length, showing a homology of 99.1%in nucleotide sequences .There were 15 consecutive bases deleted from 1a region.The systematic phylogenetic analysis demonstrated that four genotypes of NL 63 virus including A , B, C and D have been identified , and two domestic strains were belonged to the new genotype D .Conclusion The complete genome sequences of two domestic HCoV-NL63 isolates were identified for the first time .This study provided evidence for further investigation on molecular epidemiology of HCoV-NL63 in China .
ABSTRACT
The incidence and clinical features of human coronaviruses (HCoVs) among Brazilian patients with respiratory illness are not well known. We investigated the prevalence of HCoVs among Brazilian outpatients and hospitalised patients with respiratory illnesses during 2009 and 2010. To identify the HCoVs, pancoronavirus and species-specific reverse-transcriptase polymerase chain reaction assays were performed. Five of 394 samples were positive for HCoVs (1.2%): 1/182 (0.5%) outpatients and 4/212 (1.8%) hospitalised patients. The OC43 and NL63 HCoVs were identified. Two patients were admitted to the intensive care unit. Underlying chronic disease was reported in cases and one diabetic adult died. HCoVs can cause lower respiratory infections and hospitalisation. Patients with pre-existing conditions and respiratory infections should be evaluated for HCoV infections.