ABSTRACT
Haemaphysalis longicornis, the cattle tick or bush tick, has an extended distribution throughout Asia and the Pacific region, including China, Russia, the Republic of Korea (ROK), Japan, Australia, New Zealand, and the South Pacific islands. It is an obligate ectoparasite found commonly on medium to large sized wild and domestic animals, with humans as an accidental host. Haemaphysalis longicornis transmits a number of pathogens, including severe fever with thrombocytopenia syndrome and tick-borne encephalitis viruses, bacteria, helminths, and protozoans, that impact on veterinary (wild and domestic animals) and human health. Surveys of rickettsial pathogens associated with H. longicornis from China, the ROK, and Japan have resulted in the discovery of more than 35 incompletely characterized molecular isolates of Rickettsia. In response to the increased global threat of tick-borne rickettsial diseases, H. longicornis collected in the ROK and China were assessed in our laboratory and two additional Rickettsia spp. isolates (ROK-HL727 and XinXian HL9) were identified. These agents were fully characterized by multilocus sequence typing using partial gene fragment sequences of rrs, gltA, ompA, ompB, and sca4. Phylogenetic comparisons of these Rickettsia isolates with known Rickettsia species and other molecular isolates identified from H. longicornis were performed to better understand their interrelationships. Phylogenetic analysis of the sequences from these 5 gene fragments showed that ROK-HL727 was closely related to rickettsial isolates of H. longicornis previously reported from China, the ROK and Japan, but distinct from any currently recognized Rickettsia species. It therefore qualifies genetically as a new species, introduced herein as Candidatus Rickettsia longicornii. The XinXian-HL9 isolate detected from China was determined to be genetically similar to the human pathogen Rickettsia heilongjiangensis. People living and working in areas where H. longicornis is endemic should be aware of the potential for rickettsial diseases.
Subject(s)
Ixodidae/microbiology , Rickettsiaceae/isolation & purification , Animals , China , Female , Genes, Bacterial , Ixodidae/growth & development , Larva/growth & development , Larva/microbiology , Male , Nymph/growth & development , Nymph/microbiology , Phylogeny , Republic of Korea , Rickettsiaceae/classification , Rickettsiaceae/genetics , Sequence Analysis, DNAABSTRACT
OBJECTIVE: This study aimed to investigate the subtype distribution of gp41 gene of human immunodeficiency virus-1 (HIV-1) among men who have sex with men (MSM) in Zhengzhou. METHODS: Thirty blood samples were collected from men who have sex with men infected by HIV. The complete gp41 gene was amplified by RT-PCR and nested-PCR and sequenced. All sequences were edited by Bioedit and subtyped with HIV sequence library US Los Alamos National Laboratory and online genotyping software provided by American National Center of Biotechnology Information. Phylogenetic analysis of gp41 gene was performed using the MEGA 3.1 software, and the genic dispersion rates among subtype of gp41 gene were analyzed. RESULTS: A total of eighteen gene sequences of HIV-1 gp41 gene were obtained from thirty men who have sex with men infected by HIV, which belonged to subtype CRF15-01B (50% (9/18)), CRF01-AE (22% (4/18)), CRF07-B (22% (4/18)) and B (6% (1/18)), respectively. The intersubtype HIV-1 strains aggregate with according reference strains. The genetic distance inter-subtype of subtype CRF15-01B, CRF01-AE and CRF07-B were 0.050 ± 0.007, 0.052 ± 0.009 and 0.082 ± 0.012, respectively. CONCLUSION: The prevalent subtypes of HIV-1 among among MSM in Zhengzhou was complicated and recombinant HIV-1 strains were the most prevalent strains.
Subject(s)
HIV Envelope Protein gp41/genetics , HIV Infections/epidemiology , HIV Infections/virology , HIV-1/genetics , Homosexuality, Male , Genotype , Humans , Male , Molecular Epidemiology , Phylogeny , Sequence Analysis, DNAABSTRACT
To investigate the subtype distribution of human immunodeficiency virus-1(HIV-1) infection among men who have sex with men (MSM) in Zhengzhou, Henan Province, forty blood samples were collected from HIV-1 carriers, who acknowledged to have sex with men. The complete gag gene was amplified by RT-PCR and nested-PCR and sequenced. All sequences were edited by BioEdit and subtyped by genotyping software. Phylogenetic analysis of gag gene were then performed using the MEGA 3.1 software, the gene distances were calculated by Distance program. There were three different HIV-1 subtypes including B, CRF01-AE and CRF07-BC present among twenty four MSMs in Zhengzhou. Genotyping results showed that 33.33% (8/24) were B, 41.67% (10/24) were CRF01-AE and 25% (6/24) were CRF07-BC, and subtype CRF01-AE had become the most prevalent HIV-1 subtype in Zhengzhou, Henan province. In conclusion, recombinant HIV-1 strains are circulating in Henan province and the epidemiology is complicated.
