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Objective:To investigate the molecular network of HIV-1 CRF01_AE in Yunnan Province and the factors influencing it.Methods:Demographic data and plasma samples of HIV/AIDS patients in Yunnan drug resistance monitoring database from 2018 to 2021 were collected. HIV-1 pol gene fragments (protease and reverse transcriptase region) were amplified using RT-PCR and then sequenced. The optimal gene distance was selected and a molecular network was constructed based on the sequences of CRF01_AE genotype. Results:In this study, a total of 967 sequences of CRF01_AE genotype were obtained by sequencing. At the optimal gene distance threshold of 1.75%, a total of 320 sequences were involved in the network with a rate of 33.1%, and 84 clusters were identified. In the regional distribution, one cluster dominated by multiple regions, one cluster dominated by Zhaotong, one cluster dominated by Honghe and five clusters dominated by Wenshan were formed in the network. In the network, 75.8% of heterosexual men were connected with other heterosexual men and 54.1% were connected with heterosexual women. There was potential transmission among 66.7% of men who have sex with men (MSM). HIV/AIDS patients in Chuxiong, Dali, Dehong, Honghe, Lincang, Pu′er, Wenshan, Yuxi and Zhaotong were more likely to be involved in the network that those in Kunming. People who were 50 years old and above were more likely to be involved in the network than those less than 25 years old. Factors influencing HIV/AIDS patients with HIV-1 CRF01_AE infection to become high-risk transmitters in Yunnan were not found and further study on this subject was needed.Conclusions:HIV-1 CRF01_AE strains had spread actively in different regions of Yunnan Province and the transmission network was complex. Dynamic monitoring of CRF01_AE strains should be strengthened and a precise intervention for high-risk transmitters should be performed to reduce new infections.
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Objective:To analyze the variation characteristics of gag gene sequence of human immunodeficiency virus type 1 (HIV-1) epidemic strains in four major acquired immunodeficiency syndrome (AIDS) endemic areas in Yunnan Province. Methods:A total of 480 human immunodeficiency virus (HIV)/AIDS patients from designated antiviral treatment institutions in Kunming City, Dehong Dai and Jingpo Autonomous Prefecture, Hani-Yi Autonomous Prefecture of Honghe and Lincang City in Yunnan Province from January 2019 to December 2020 were randomly selected. The epidemiological information of the patients was collected. The plasma samples were collected and sent to the Yunnan Provincial Infectious Diseases Hospital for analysis. HIV-1 gag gene was amplified by nested polymerase chain reaction for genotyping.The phylogenetic tree was constructed by MEGA 6.06, and the characteristic amino acids were analyzed by VESPA online analysis tool. The gene distances of gag and matrix protein p17, capsid protein p24, nucleocapsid protein p7 and p6 protein of gag protein were calculated by Distance program. The ratio of synonymous mutation frequnency and non-synonymous mutation frequnency (Ks/Ka) was analyzed by SNAP program. Statistical comparison among multiple groups was performed using analysis of variance. Results:The gag gene sequences were successfully obtained from 404 patients.Most of these patients were men (250 cases, 61.9%), 59.7%(241/404) of patients were aged 40 to 59 years, and the main transmission route was heterosexual transmission (61.4%, 248/404). The main epidemic subtypes of HIV-1 were circulating recombinant form(CRF)08_BC (38.4%, 155/404), CRF01_AE (18.3%, 74/404), unique recombinant form (URF) (12.9%, 52/404), CRF07_BC(9.7%, 39/404), C subtype (8.4%, 34/404), other subtypes (6.9%, 28/404) and B subtype (5.4%, 22/404). Two main spreading clusters were formed by CRF08_BC in the phylogenetic tree, and there were significant differences in the distribution of characteristic amino acids of eight loci between the two spreading clusters, including No.79, 93, 121, 122, 151, 363, 395 and 396. The gag gene distances of CRF01_ AE, CRF07_ BC and CRF08_ BC were 0.090±0.004, 0.088±0.004 and 0.078±0.002, respectively, and the difference was statistically significant ( F=118.33, P<0.001). The Ks/Ka values of gag of the three subtypes were 4.003±1.309, 4.141±0.860 and 4.514±1.215, respectively, and the difference was statistically significant ( F=1.35, P<0.001). The Ks/Ka values of p17 were 2.590±0.186, 2.831±0.496 and 2.936±0.475, respectively, and the difference was statistically significant ( F=1.59, P<0.001). The Ks/Ka values of p24 were 12.579±1.116, 10.185±0.494 and 8.522±0.595, respectively, and the difference was statistically significant ( F=1.61, P<0.001). The Ks/Ka values of p7 were 10.850±0.711, 9.717±0.932 and 8.522±0.026, respectively, and the difference was statistically significant ( F=4.24, P<0.001). The Ks/Ka values of p6 were 3.122±0.134, 3.040±1.498 and 4.841±0.353, respectively, and the difference was statistically significant ( F=10.68, P<0.001). Conclusions:CRF08_ BC is the main subtype in these four areas in Yunnan Province.The different clusters of CRF08_BC result in a different pattern of amino acid composition.The variation degree of different subtype gag gene is different in each section. Surveillance of HIV variant strains should be strengthened to control the epidemics of HIV.
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Objective To investigate the influence factors of mortality among human immunodeficiency virus (HIV)-infected children under highly active antiretroviral therapy (HAART).Methods Retrospective cohort study of 652 children initiated HAART from 2005 to 2014 was conducted,and enrolled patients were followed-up until December,2015.Survival data was analyzed using Kaplan-Meier method and Cox regression model was used to identify independent predictors of mortality among these children on HARRT.Chi-square test and Fisher's exact test were used for comparison between groups.Results Overall,26 of the children died over a follow-up period of 3 116.24 child-years,with a mortality rate of 0.83 per 100 child-years.Twelve (46％)of deaths occurred during the first six months after starting HAART.Cox regression analysis of variables showed that the World Health Organization (WHO) clinical stages Ⅲ/Ⅳ (hazard rate [HR] =10.717,95％confidence interal [95％ CI]:4.189-4.749,P =0.000),baseline hemoglobin ＜ 80 g/L (HR =14.768,95 ％ CI:5.721-38.125,P =0.000),tuberculosis co-infection (HR =4.794,95％ CI:2.105-10.918,P =0.000),baseline CD4+T lymphocyte ＜ 50 cells/μL (HR =4.219,95％ CI:1.524-11.680,P =0.006),weight-for-age z-score ＜-2 (HR =2.983,95 ％ CI:1.094-8.135,P =0.033) were independently associated with death,whereas the age ＜ 7 year-old at HAART initiation was protectire (HR =0.293,95％ CI:0.126-0.684,P =0.005).Conclusions The mortality of children receiving HAART is strongly associated with WHO stages Ⅲ/Ⅳ,hemoglobin ＜ 80 g/L,weight-for-age z-score ＜-2,tuberculosis co-infection and older age at treatment.
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Objective To analyze the genetic structure and recombination characteristics of a new-ly discovered HIV-1 unique recombinant strain in Yunnan Province. Methods During a test for drug-resist-ant HIV genotypes in Yunnan Province in 2016, a recombinant fragment was found in the pol region of a HIV-1 strain isolated from a patient. Two overlapping segments of the HIV-1 genome were amplified by RT-PCR, and then the products were sequenced. Recombination analysis was performed using RIP, jpHMM and SimPlot3. 5 software. A phylogenetic tree was constructed for homology analysis by Neighbor-joining method using MEGA6. 06 software. Results A nearly full-length HIV-1 gene sequence with 8590 bp in length was obtained. Breakpoint analysis indicated that the sequence consisted of CRF01_AE and fragments of B and C subtypes. CRF01_AE was used as the backbone with B and C subtype fragments inserted. The positions were 791 to 1171 for CRF01_AE, 1172 to 2652 for C subtype fragment, 2653 to 2977 for B subtype frag-ment, and 2978 to 9380 for CRF01_AE using HIV-1 HXB2 as the reference strain. Conclusions Some new strains formed by cross-recombination of CRF01_AE and B and C subtypes were discovered in Yunnan Province in recent years. It was found that the recombination pattern of the newly discovered strain was com-plex, suggesting that close attention should be paid to the changes in epidemic trends, which was of great im-portance to understand the current prevalence and epidemic trends of HIV-1.
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Objective To evaluate the long-term efficacy of antiretroviral therapy and drug resistance among human immunodeficiency virus-1(HIV-1)-infected children in Yunnan.Methods In this retrospective study,CD4+T cell counts,HIV viral loads and genetic drug resistance results were obtained from HIV-1-infected children who were treated with antiretroviral treatment between January 2004 to July 2015.Results A total of 1 078 HIV/acquired immune deficiency syndrome(AIDS)children were treated with antiviral therapy.Before treatment,the average CD4+cell number was(466.8 ± 397.2)cells/μL. The percentages of children with CD4+cell count >750 cells/μL after 1-year,3-year,5-year and 8-year treatment were 54.31%,62.87%,68.46% and 74.19%,respectively.Virological failure occurred in 150 HIV/AIDS children(13.9%),and the virological failure rate was 4.3/100 child-years.Among those 150 patients with virological failure,104 cases(69.33%)exhibited genetic resistance to antiretroviral drugs.The prevalent mutations associated with drug resistance were M 184V/I(75.0% [78/104]), K103N(43.3%[45/104]),G190A(29.8%[31/104]),Y181C(22.1%[23/104]),T215Y/F(20.2%[21/104]).Conclusions After long-term antiretroviral treatment,most of the HIV-infected children have restored the immunity and suppressed HIV viral replication successfully.HIV resistance is the main cause of virological failure.Drug resistance mutations mainly occur in nucleoside reverse transcriptase inhibitor and non-nucleoside reverse transcriptase inhibitor,and the resistance rate of proteinase inhibitor is low.Early genetic resistance testing and switch to second-line therapy will improve the treatment outcome.
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Objective To investigate the subtypes distribution of human immunodeficiency virus (HIV)-1 epidemic strains and the characteristics of amino acid variation in different areas of Yunnan Province.Methods Totally 800 HIV/AIDS plasma specimens and epidemiological information were collected between 2012 and 2015 from 14 areas of Yunnan.Viral RNA was extracted and amplified using RT polymerase chain reaction (PCR).4.5 kb 5'halves fragments were obtained and directly sequenced.Subtypes of strains were identified by Genotyping,MEGA 6.06 and BLAST.Grouping was analyzed by location and subtype.Entropy software was used to analyze the difference of amino acid sequences between different groups according to the sampling location and subtypes to analyze the regional distribution and genetic variation of HIV-1 subtypes in Yunnan Province.Results Of the 800 plasma specimens,a total of 446 genomic sequences from 12 areas were successfully amplified and sequenced.After genotypes were identified,the subtypes of HIV-1 strains prevalent in Yunnan were CRF08_BC (58.3％),CRF01_AE (19.3％),CRF07_BC (11.6％),unknown recombinant forms (7.1％),B(B') (1.7％) and C (1.3％).The geographical distribution in Yunnan was analyzed.The CRF01_AE predominated in Dehong,Xishuangbarma and Wenshan.The CRF08_BC predominated in Lincang,Honghe and Puer (more than 70.0％) and CRF08_BC was prevalent in the other areas.But CRF07_BC in Kunming,Yuxi and Dali accounted for more than 20 ％.The constitutions of amino acid of three majors CRF08_BC,CRF01 _AE and CRF07_BC were different on 17,14 and 18 amino acid sites with statistical differences in the eastern and western regions of Yunnan Province (均P ＜ 0.05).Conclusions HIV-1 strains transmit and vary genetically in the province widely.The amino acid mutation sites of eastern and western strains are different.This difference represents that the same subtype strains in different geographical distribution vary on different genetic background and are selected by immune responses.The epidemic trends need to be closely monitored.
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Objective To investigate the variations in the pol region of HIV-1 strain in treatment failed patients in Yunnan province's Dehong prefecture and Kunming. Methods Blood samples were collected from 139 patients who experienced treatment failure ( HAART treatment ＞ 1 years and HIV-1 RNA Viral load ＞ 1 000 copies/ml). HIV-1 RNA was extracted from plasma, and nested-PCR was performed for amplification of PR and RT genes on the HIV-1 pol region. The PCR products were then sequenced and submitted to Stanford HIV Drug Resistance Database for comparison. The evolution tree was built up with MEGA 4. 1 system, combined with patients' demographics. Results The most prevalent mutation in Kunming patients were T215F/N/Y/I, M41L/M, and T69G/N/I/S/A/D, the mutation rates were 39%(24/62), 27% (17/62) and 27% (17/62) , respectively, which were higher than the corresponding mutations in the Dehong prefecture [16% ( 11/69), 13% (9/69) and 9% (6/69)]. The rate differences were statistically significant ( x2 = 8.646, 4.242 and 7. 909, all P ＜ 0.05 ). The most common HIV-1 pol region subtype in the Dehong patients were CRF01_AE subtype (32%, 22/69), followed by C subtype (25% ,17/69), and B subtype ( 19%, 13/69). Major subtypes in Kunming patients were 08_BC (60%,37/62 ), CRF01_AE subtype(21% , 13/62 ) and 07_BC ( 15% ,9/62). Conclusions Partial differences of the point mutations of the HIV-1 strain pol region and frequency of their occurrences exist among Dehong and Kunming patients, HIV-1 strains in Dehong prefecture for the NNRTIs mutations at the T215 Y/N/T, M41L and T69G/N/I/S/A/D are significantly higher than those in Kunming. Six isoforms are found respectively:CRF01_AE, B, C, BC, 08_BC and 07_BC from the epidemic strains of HIV-1 pol region subtype in Dehong and Kunming areas.