Clinical significance of bispectral index monitoring in patients with acute severe carbon monoxide poisoning / 中华劳动卫生职业病杂志

Objective: To analyze the correlation of bispectral index (BIS) with the prognosis of patients with acute severe carbon monoxide poisoning (ASCMP) and its predictive value of adverse outcomes. Methods: In March 2021, 106 ASCMP patients who were treated in Harrison International Peace Hospital Affiliated to Hebei Medical University from January 2019 to December 2020 were taken as research objects. All patients underwent 24-hour BIS monitoring after admission, and were divided into good prognosis group (n=75) and poor prognosis group (n=31) according to the prognosis of the patients' cranial nerve function after 60 d. The general conditions, Acute Physiology and Chronic Health Evaluation Ⅱ (APACHEⅡ) score, Glasgow Coma Scale (GCS) score at admission and 24-hour BIS mean were compared between the two groups. Pearson correlation analysis was used to analyze the correlations between the 24-hour BIS mean and GCS score at admission, APACHEⅡ score and coma time. The receiver operating characteristic (ROC) curve was drawn to analyze the predictive value of 24-hour BIS mean, GCS score at admission, APACHEⅡ score and coma time on adverse outcome of ASCMP patients. Results: The coma time and APACHEⅡ score of the patients in the poor prognosis group were significantly higher than those in the good prognosis group, the GCS score at admission and 24-hour BIS mean were significantly lower than those in the good prognosis group (P<0.05) . Pearson correlation analysis showed that the 24-hour BIS mean was positively correlated with the GCS score at admission, and negatively correlated with the APACHEⅡ score, coma time (r=0.675, -0.700, -0.565, P<0.001) . The 24-hour BIS mean had the highest predictive value for adverse outcome of ASCMP patients, with a cut-off value of 74, the area under the curve was 0.883 (95%CI: 0.814-0.951, P<0.001) , and the sensitivity and specificity were 73.3% and 87.1%, respectively. Conclusion: The 24-hour BIS mean has a good correlation with the acute brain nerve injury, the severity of the disease and coma time of patients with ASCMP. And it has a high predictive value for the adverse outcome in patients with ASCMP.

Distribution of HIV-1 subtypes in Guangxi Zhuang Autonomous Region, 2008-2009 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the distribution of HIV-1 subtypes in Guangxi Zhuang Autonomous Region.</p><p><b>METHODS</b>294 participants who were infected by HIV-1 in 2008 - 2009 and residing in 13 cities in Guangxi were enrolled into this study. Epidemiological information showed that heterosexual transmission was the main transmitting route. 1584 bp full length gag gene, 3147 bp full length pol gene and 558 bp env (C2V3) fragments were amplified by using RT-PCR and then directly sequenced. NCBI genotyping tool and Mega 5.03 software were used to determine the HIV subtypes. Simplot and Recombinant HIV-1 Drawing Tool were used for the analysis of recombination.</p><p><b>RESULTS</b>A total of 739 sequences, including 270 gag, 246 pol and 223 env (C2V3), were successfully obtained from 294 plasma specimens. Genotypes of HIV from 272 participants were determined. CRF01_AE was found the dominant (77.6%), followed by CRF08_BC (10.7%) and CRF07_BC (7.4%). 7 unique recombinant forms, 4 subtype B (B') and 1 subtype G were also identified. No significant difference on the distribution of subtypes among different regions and ethnics was found. Among the 7 unknown recombinant forms, 6 strains were mosaic B and/or C fragments with CRF01_AE genome as the backbone, while one strain originated from CRF07_BC and CRF08_BC.</p><p><b>CONCLUSION</b>Currently, CRF01_AE was found the major subtype of HIV epidemic in Guangxi. New recombinant forms with CRF01_AE as backbones had been emerging, which called for serious attention.</p>

HIV-1 subtype and the distribution in Yunnan province / 中华流行病学杂志

Objective To understanding the genetic subtype and its population and regional distribution of HIV-1 strains circulating in Yunnan province.Methods 788 plasma specimens collected in 2008-2009 from 15 distracts of Yunnan,were enrolled.Viral RNA were extracted and subjected to RT-PCR.1584 bp full length gag gene,3147 bp full length pol gene and 558 bp env (C2V3) fragment were amplified and directly sequenced.Full length gag and pol genes were connected together as a complete genetic region (location on HXB2:790-5096) for genotyping.Results Of the 788 plasma specimens,a total number of 1728 genomic sequences including 599 gag,564 pol and 525 env (C2V3) were successfully amplified and sequenced,with genotype of 617 samples identified.The subtypes of HIV-1 strains circulated in Yunnan were with the order of constituent ratio CRF08_BC ( 50.2％ ),CRF01_AE (25.0％),unknown recombinant forms ( 10.2％ ),CRF07_BC (9.2％),subtype C (2.9％) and subtype B (B') (2.4％).The distributions of subtypes showed significant regional differences and could be roughly divided into two forms:the CRF08_BC predominant areas represented by Lincang and Kunming,and the areas with CRF08_BC together with CRF01_AE coexistence,represented by Dehong and Xishuangbanna.The unknown recombinant forms accounted for more HIV infection in ethnic minorities (17.0％) than in ethnic Han (6.7％,P＜0.01 ).The distribution of subtypes varied significantly in the two primary routes of transmission for those infected through heterosexual contact.CRF08_BC and CRF0 1_AE were the dominant subtypes,accounting for 52.7％ and 29.1％ respectively.However,in IDUs,CRF08_BC strains accounted for half of the infection,while only 4.5％ of the infections were caused by CRF01_AE,CRF07_BC while the unique recombinant forms were responsible for 15.5％ infections.Of the 63 unknown recombinant forms,most (74.6％) were B (B' ) recombinant with C,while 25％ were mosaic B and/or C fragments on the bases of CRF01_AE genome.Conclusion The subtypes of HIV-1 strains circulated in Yunnan were complicated under the significant differences of regions,ethnics or routes of transmission.

Studying on the prevalence and mutation pattern of N348I which related to the resistance of HIV-1 / 中华流行病学杂志

Objective To elucidate the prevalence and the mutation pattern of N348I that related to the resistance seen in the AIDS patients, in China. Methods Partial pol gene of HIV-1 comprising of full protease (PR) and reverse transeriptase (RT) was obtained from plasma samples of therapy-failure individuals (n=614) and therapy-naive individuals (n=619) by using reverse transcription polymerase chain reaction(RT-PCR). 1233 sequences were then submitted to the HIV-1 drug resistance database of the Stanford University to analyze the prevalence and the emergence pattern of N348I. Results The prevalence of N348I was 6.5％ in the therapy-failure patients and 0.8％ in the naive individuals, respectively. The prevalence of N348I was more popular among those patients whose ART regimens containing zidovudine (AZT or ZDV) than those without AZT in regimens( 14.1％ vs. 4.7％, x2=10.21, P＜0.01 ). N3481 always emerged, and combined with others mutations among patients of ART, whose frequencies were: 85.0％ in combination with thymidine analog mutations (TAMs) and 52.5％ with M184V/I, respectively. Conclusion N348I was somehow prevalent in the therapy-failure patients when using the first-line antiretroviral drugs,and it emerged as unique patterns. This study laid the ground in improving the techaology of drug resistance genotypes detection and providing theoretical basis to study the mechanism of resistance and the law of molecular evolution.

Screening program on novel drug resistance mutations of subtype B' in human immunodeficiency virus type 1 in China / 中华流行病学杂志

Objective To screen the level of novel drug resistance mutations in subtype B' in China. Methods 451 pol sequences collected from the previous study, which including 354 AIDS patients who had received antiretroviral treatment(ART)and 97 the untreated patients. Entire protease gene(codous 1-99)and full-length reverse transcriptase gene(codons 1-560)were included.Variation of mutations between the treated and the untreated patients with consensus/ancestral sequences were compared and the mutations with higher frequencies in the treated patients than in the untreated patients were screened before submitting the mutations to the Stanford HIV Drug Resistance Database(SHDB)(http://hivdb.stanford.edu/). Relation between the mutations and resistance preliminarily was then analyzed, according to the information including SHDB. Results Frequencies of 7 mutations at 6 positions, DI23E, V292I, K366R, T369A, T369V, A371V and 1375V, 2 at DNA polymerase domain and 5 at connection domain of reverse transcriptase(RT)were higher in the treated patients than in the untreated patients. The information of 7 mutations including the SHDB showed that 7 mutations were major variants at corresponding positions, and theirs frequencies were higher in the treated patients using some drugs, than in the untreated patients. Conclusion 7mutations being screened from the China subtype B were possibly associated with the resistance,which called for the construction of mutated viruses by site-directed mutagenesis to identify their effects on the susceptivity of different drugs.

Allele-specific real-time PCR testing for minor HIV-1 drug resistance mutations: assay preparation and application to reveal dynamic of mutations in vivo / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It is very important for the clinical management to test for minor HIV-1 resistance mutations accurately and sensitively. The conventional genotypic assays of HIV drug resistance detection based on sequencing can only discriminate the mutations which present in more than 20% - 30%. The aim of this study was to evaluate allele-specific real-time PCR (ASPCR) to detect the resistance-related mutations located at positions 103, 184 and 215.</p><p><b>METHODS</b>We developed the allele-specific PCR assay, using the most common drug resistance mutations in Chinese AIDS patients, K103N, M184V/I, T215F/Y as a model system. The standards were constructed by cloning the wild-type and mutant DNA fragments into the T-vector. We designed specific primers to discriminate mutant templates in the real-time PCR using SYBR green as a fluorescence reporter. And then we evaluated the ASPCR assay and tested 140 clinical samples using this method.</p><p><b>RESULTS</b>The sensitivities of ASPCR assay were 0.04% for K103N, 0.30% for M184I, 0.40% for M184V, 0.03% for T215F and 0.02% for T215Y. The intra-assay and inter-assay coefficients of variation were less than 0.42. One hundred and forty plasma samples were tested by ASPCR and dynamic resistance curves of ten patients were obtained.</p><p><b>CONCLUSIONS</b>Drug resistance emerged half a year after the start of antiretroviral therapy. The mutation of T215Y emerged 1 to 1.5 years after starting treatment and then increased rapidly. The ASPCR assay we developed was a sensitive, accurate and rapid method to detect the minor HIV-1 variants and it can provide earlier and more drug-resistance information for HIV research and AIDS antiretroviral therapy.</p>

Evaluation on HIV antibody testing strategy currently used in China / 中华流行病学杂志

Objective To evaluate the yield of HIV antibody testing strategy currently used on different populations, in China. Methods (1) The following samples were collected and tested according to the currently used HIV antibody testing strategy in China. 103 133 samples from the general populations (outpatients, new recruits and blood donors), 1276 people under high risk (spouses of the HIV infected individuals, intravenous drug users) and 2323 biochemical or immunological abnormal samples. (2) Retrospective analysis was done on data from the HIV testing among outpatients in General Hospital of People's Armed Police Forces, from Jan., 2002 to Dec.,2008 and in three provincial central HIV test and confirmatory laboratories. Results (1) The yields of HIV antibody screening were significantly different in different populations. The probability of screening reactive to be true positive was 50% in high risk population, significantly higher than in the general population. The probability of screening reactive to be true positive was 19.58% in the confirmatory laboratory mainly towards the general population, but significantly lower than results from the confirmatory laboratories done on the high risk population. (2) From 2002 to 2008, in the General Hospital of People's Armed Police Forces, the probability of screening reactive to be true positive in the clinical HIV test was increasing from 3.7% to 16.0%, where as the efficiency of the repeat screening testing decreased from 92.6% to 61.5%. Conclusion The predictive value of HIV antibody screening reactive was significantly greater in high risk population than in general population. The precision of HIV antibody initial screening was substantially increased with the improvement of HIV antibody test kits and of quality control in the HIV test laboratories in recent years. It is suggested that different HIV test strategies to be implemented in different populations.

Subtype and characterization of gag gene of HIV-1 strains prevalent in some areas of China / 军事医学科学院院刊

Objective:To investigate the subtype distribution of HIV-1 strains prevalent in four areas of China,and to study the characteristics of gag gene variation and changes in antigen epitopes under the host immune pressures. Methods:The plasma of HIV-1 infected people from Henan, Guangdong, Sichuan and Beijing in China were collected. Virion RNA was extracted directly from plasma after the virion was condensed. The gag gene was amplified by RT-PCR and nested-PCR.Sequences were subtyped by Genotyping Tool software, and phylogenetic analysis of gag gene were performed using the MEGA 4.1 software.The gene distances intra each subtype were calculated by Distance program. The Ks/Ka ratios were calculated using SNAP program. The variation analysis of CTL antigen epitopes restricted by main HLA-Ⅰ specificities in China was performed.Results:Six subtypes or circulating recombinant forms(CRFs)of HIV-1,including B',CRF07_BC,CRF01_AE,B,CRF08_BC and CRF02_AG,were identified in four areas of China.The gene distances intra each subtype were CRF01_AE>B>CRF08_BC> CRF07_BC>B' listed in order of size, meanwhile the order of Ks/Ka ratios was CRF01_AE>B>CRF08_BC>B'>CRF07_BC. Far more diversity of antigen epitopes in P17 region was observed than that in P24.Epitope mutations intra subtypes were CRF01_AE>B>B'>CRF07_BC listed in order of size. Conclusion:Itseems that CRF01_AE is under the strongest immune pressures,and displays the most diversity of gene and variation of epitopes intra subtypes prevalent in China, followed by subtype B, B' and CRF07_BC. The discrepancy of epitope mutations intra the subtypes is significant.

Competitive capacity of HIV-1 strains carrying M184I or Y181I drug-resistant mutations / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Virus with nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse transcriptase inhibitors (NNRTIs) resistant mutations show different evolution tendencies when the anti-viral therapies are interrupted. Understanding the replication fitness of drug-resistant virus is important for the study of the prevalence of drug-resistance. For this purpose, we characterized the replication capacity of HIV-1 virus carrying lamivudine (3TC) or nevirapine (NVP) resistant mutations.</p><p><b>METHODS</b>3TC and NVP resistant variants were induced in vitro by selecting wild type virus in the presence of drugs. For the competitive replication assay, drug-resistant variants were cocultured with wild-type virus in the presence or absence of drugs. The ratios of the viral species were determined over time by using a real-time RT-PCR-based assay.</p><p><b>RESULTS</b>3TC-resistant (M184I mutation) and NVP-resistant (Y181I mutation) virus should be selected in vitro in two different ways. The competitive replication assay showed that the ratio of virus carrying a M184I mutation increased from 98.8%, while the wild type virus decreased to 1.2% after 4 passages in the presence of 3TC; the percentage of virus carrying the Y181I mutation increased to 90.5%, while wild type virus decreased to 9.5% in the presence of NVP. In the absence of drugs, the ratio of virus carrying the M184I mutation decreased to 5.3%, while wild type virus increased to 94.7%; the ratio of virus carrying Y181I increased to 75%, while wild type virus decreased to 25% after 4 passages.</p><p><b>CONCLUSIONS</b>The NVP-resistant virus is fitter than wild type virus even in the absence of NVP that may be the reason that NNRTIs-resistant virus is spreading quickly.</p>

Study on the indeterminate results of characterization and verification of HIV antibody from Western blot test / 中华流行病学杂志

Objective To study the serological characterization of indeterminate Western blot(WB)results of HIV antibody and to find a new way to verify the HIV antibody indeterminate results and provide references for editing"National Guideline for Detection of HIV/AIDS".Methods All of the 42 subjects who were confirmed as indeterminate HIV antibody in People'Libaretion Amry HIV Confirmation Laboratory from 2005 to 2006,were collected.Line immunoassay.HIV viral load test and HIV-1 p24 were tested and followed up for 3-6 months'to compare the changes of WB bands patterns.Results (1)For the 42 individuals with indeterminate HIV antibody.a total of 8 different patterns of bands were found in WB test including 45.2% of them were p24 monoband,30.9% were gp160 monoband,11.9% were gp160 with p24,2.4%(only one case)were gp160gp120 ±,gp41p24,p24p17,gp41 or gp120respectively.It was noticed that the most patterns of common bands with indeterminate results were p24 monoband.gpl60 monoband and gpl60 with p24.which composed 88.0% of the whole indeterminate WB band patterns.(2)Twenty three cases had been followed up for more than 3 months with 22 giving no WB band image change and were confirmed as HIV sero-negative.The other one with case gp160 and p24 had developed to more bands in the period of 77 days follow-up with more bands,including gpl60,gp120,p66,p31,p24 and p17,showed up and was confirmed as HIV primary infection.(3)Line immunoassay was applied to all of those 23 cases who had been followed up and the results showed that only one serological change was found and the case was confirmed to be HIV-positive.Among the other 22 cases without serological changes.16 cases were proved to be HIV-negative,6 cases were still indeterminate.The specificitv was 72.7%.P24 antigen test showed negative in all the 23 cases,including the case which later was confirmed as HIV-positive.Of all the 23 originally indeterminate cases,viral loads were tested in 7 eases.Positive result was found in the case which was proved later to be HIV-positive.No viral loads were detected in the other 6 cases(＜LDL).Conclusion The most common band patterns of indeterminate HIV antibody were mainly p24 monoband,gp160 monoband or with p24.Most of them (95.6%)were not infected by HIV,the bands showed up in WB test and demonstrated as non-specific reactions.Line immunoassay could determine about 70% of the indeterminate reactions.Results from viral load test also suggested that it was an efficient method to discriminate indeterminate results.With these two techniques,HIV serology could be diagnosed without 3 months'follow-up in primary infection which gave indeterminate WB results.

Research on the selective kinetics of HIV-1 nucleoside reverse transcriptase inhibitor drug resistance-associated mutations among 4 AIDS patients receiving highly active antiretroviral therapy / 中华流行病学杂志

<p><b>OBJECTIVE</b>To elucidate the molecular evolutional characteristics of HIV-1 nucleoside reverse transcriptase inhibitor (NRTI) drug resistance-associated mutations in patients with AIDS receiving highly active antiretroviral therapy.</p><p><b>METHODS</b>We selected 4 AIDS patients receiving highly active antiretroviral therapy (HAART) with good adherence under a HIV-1 drug resistance cohort from a rural region in central China. Those people carried susceptible virus at the beginning of treatment and gradually came to produce virus resistant to NRTIs during the process of antiretroviral therapy (ART). Reverse transcriptase (RT) genes from each patient's peripheral blood samples (from 3 to 33 months after withdrawal) were cloned and sequenced in succession.</p><p><b>RESULTS</b>We sequenced a total number of 855 clones and obtained the HIV-1 NRTI drug resistance-associated mutations patterns of the 4 patients. Typical resistance mutations of thymidine analogue mutations (TAMs) pattern 1, such as L210W, T215Y and M41L, were generated in patient 'A'. TAMs pattern 2, including D67N, K70R and K219Q mutations, was discovered in patient 'B'. Interestingly, in patient 'C', some clones comprising not only TAMs pattern 1 mutations (T215Y) but also TAMs pattern 2 mutations (K70R, D67N).</p><p><b>CONCLUSION</b>The four patients show different pathways on HIV-1 NRTI drug resistance-associated mutations, including TAMs pattern 1, TAMs pattern 2 and the fusion pattern of TAMs-1 & TAMs-2. We also noticed that the tendency of gradual accumulation was obvious and those mutations detected earlier tended to be the predominant strains.</p>

Study on the difference of the APOBEC3G mRNA levels among HIV long-term nonprogressors, slow progressors, people at high risks and normal people / 中华流行病学杂志

Objective To examine the APOBEC3G(hA3G)mRNA levels of four different groups in the human immunodeficiency virus(HIV)prevalent areas in central China and to analyze the relationship between hA3G mRNA levels and HIV disease progression.Methods We collected peripheral blood and isolated the peripheral boold monouuclear cells(PBMCs),and then cryo-preserved the PBMCs in liquid nitrogen.Prior to the total extraction of RNA,PBMCs were resuscitated and mRNA were reverse Transcripted to cDNA in vitro.Real-time polymerase chain reaction(PCR)was used to test hA3G mRNA levels of different groups.Results There were 13 HIV long term non-progressors with the mean CD+4 T lymphocyte count as(716±169)per μl and the mean affection time as(12.5±2.3)years.There were 48HIV slow progressors with the mean CD+4 T lymphocyte count as(233±144)per μl and the mean affection time as(10.7±2.2)years.The hA3G mRNA level of HIV long term nonprogressors was higher than that of normal people while the hA3G mRNA level of HIV slow progressors was higher than that of normal people and high risk people.There were no correlations between CD+4 T lymphocyte count and hA3G mRNA levels of HIV long term nonprogressors as well as in HIV slow progressors.Conclusion There was difference found in the hA3G mRNA levels of four groups in the HIV popular area in central China while no correlation between CD+4 T lymphocyte count and hA3G mRNA levels of HIV long term nonprogressors as well as in HIV slow progressors were found.

Study on the antiviral therapy program among people with human immunodeficiency virus in Guangxi Zhuang Authority / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the reconstitution of immune function and viral suppression condition and to analyze the occurrence of drug resistance HIV-1 variants and its prevalence after using HAART in Guangxi Autonomy Region.</p><p><b>METHODS</b>From July 2004 to October 2005, 133 HIV infected individuals who had received HAART for more than three months were recruited, and 58 infected persons with no antiviral therapy were selected as controls. Questionnaire was used to collect information about the adherence of HAART therapy. Immune reconstruction and viral suppress conditions were obtained by CD4+ counts and viral load and RT-PCR were used to amplify the PR and RT regions of HIV-1 genome while HIV-1 drug resistance rates were analyzed to show the occurrence and prevalence in both treated and naive patients.</p><p><b>RESULTS</b>In terms of CD4+ T cell counts: 70.69% of the treated patients showed obvious increase and 23.28% had no apparent change but 6.03% of them went down. 70.48% of the patients who had received antiviral therapy more than 3 months had their viral load lower than the low detectable limitation. When comparing the log of viral load between treated and untreated cohort, the mean value of the treated was obviously less than the untreated (P < 0.05). However,the result of drug resistance showed no obvious difference between the treated and untreated groups.</p><p><b>CONCLUSION</b>The antiviral therapy being used in Guangxi region, had achieved obvious effect on the reconstruction of immune system and the suppression of viral replication in vivo under good adherence while the occurrence of drug-resistant HIV strain did not show obvious difference between treated and naive patient groups.</p>

Phenotypic resistance of resistant strains of HIV type-1 subtype B in China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>This study was aim to explore the characteristics of phenotypic resistance of resistant strains of HIV type-1 (HIV-1) subtype B and to compare the concordance between the phenotypic resistance and genotypic resistance.</p><p><b>METHODS</b>The genotypic resistance assay for the HIV-1 clinical isolates was performed. One isolate without resistance mutation was chosen as a drug-sensitive reference strain and seven subtype B isolates with resistance mutations were phenotypically tested. Fifty percent inhibitory concentrations (IC50) between resistant and sensitive viruses were compared. The resistance extent was determined by the folds of the increased IC50. The concordance between the phenotypic resistance and genotypic resistance was also analyzed.</p><p><b>RESULTS</b>IC50 of resistant isolates were 0.0006 - 0.1300 micromol/L for zidovudine (AZT), 0.0016 - 0.0390 micromol/L for lamivudine (3TC), 0.0104 - 0.4234 micromol/L for nevirapine (NVP), and 0.0163 - 0.1142 micromol/L for indinavir (IDV), respectively. Genotypic and phenotypic resistance assays indicated that the resistant strains were intermediately and highly resistant to nucleotide analog reverse transcriptase inhibitors and non-nucleotide analog reverse transcriptase inhibitors. The phenotypic assay was consistent with the genotypic assay. For measuring the potential resistance, the genotypic assay was more sensitive than the phenotypic. In evaluating the resistance to protease inhibitors, these two assays were discrepant.</p><p><b>CONCLUSIONS</b>Both the phenotypic and genotypic assays indicate that the resistant viruses exist in HIV-infected patients in China who have received treatment. Phenotypic and genotypic assays have high concordance, and the genotypic assay could replace the phenotypic assay to predict the HIV-1 resistance.</p>

Cohort study on human immunodeficiency virus discordant couples in the countryside of central China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To establish a cohort of human immunodeficiency virus (HIV) discordant couples for follow-up studies and to collect data on frequency of HIV heterosexual transmission and related factors.</p><p><b>METHODS</b>A total of 52 HIV discordant couples were identified by face to face interview and serological testing, in which the HIV negative individuals had no HIV infection behaviors including injecting drug use, blood transfusion or having sexual partners other than his/her own wife/husband. Three times of follows-up studies were carried out in 0.5 year, 1 year and 2.5 years to collect information on their sexual practices and condom use through face to face interview together with 20 ml whole blood collected to test HIV antibody, CD4+ T cell count and viral load.</p><p><b>RESULTS</b>(1) In the period of 2.5 years follow-up, no HIV seroconversion and HIV transmission was found. (2) The frequencies of sexual intercourse between once per month to once per week were 65.4%, 72.9%, 71.7% and 80.0% at the time of cohort setup: 0.5 year, 1 year and 2.5 years of follow-up respectively. The rates of "occasional use" to "never use" condoms were 76.9%, 66.6%, 69.1% and 60.0% at the time of cohort setup as: 0.5 year, 1 year and 2.5 years of follow-up, respectively. No significant difference between different times of follow-up for sexual intercourse or condom use. (3) 85.4%, 66.6% and 60.0% of the HIV positive individuals kept their CD4+ T cell count stabilized or raised during the 0.5 year, 1 year and 2.5 years follow-up period, respectively. However, 66.7% of them showed stable or declined viral load in the period of 2.5 years follow-up. It appeared that stable or raised CD4+ T cell and the stable/declined viral load happened simultaneously.</p><p><b>CONCLUSION</b>No transmission was identified in this study. The stabilized CD4+ T cell count and viral load might be account for the reason of no transmission while the biological factors from host and virus related with transmission need to be further studied.</p>

Study on factors associated with heterosexual-transmission of human immunodeficiency virus in central China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the factors of the human immunodeficiency virus (HIV) associated with sexual-transmission in central China.</p><p><b>METHODS</b>(1) Cross-sectional study: couples that one was HIV positive were selected in Henan and Hebei province of China. The couples must be 20 - 50 years old with normal function on sexual intercourse. Cordant couples that subsequently infected partners were at risk of infection solely through sexual contact with the HIV-seropositive partner and the discordant couples that the seronegative partners were at risk of infection solely through sexual contact with the HIV-seropositive partner, were selected. Plasma viral load, CD4 cell count were tested. (2) Case-control study was used to compare 7 sexual transmitted cases and 56 nontransmitted controls with respect to the frequency of sexual intercourse, plasma viral load and CD4 cell count.</p><p><b>RESULTS</b>(1) A total of 87 couples that at least one partner was HIV positive were recruited include 56 discordant couples and 7 cordant couples with whom sexual transmission had happened. The rate of sexual transmission was 11.1% among those at the risk of sexual transmission. (2) Of the discordant couples, male positive rate 25%, female positive was 75%. (3) The risk for transmission was higher in those couples with the frequency of unprotected vaginal sexual intercourse (> or = 4 times per month) than the reference group (< 4 times per month) (Fisher's exact test, P = 0.047, OR = 8.0). Median plasma viral load was significantly higher in the antecedent infected partners of cordant couples than the positive partner of discordant couples (378,285.71 vs 136,578.57 copies/ml, t = 3.591, P < 0.01). The odds ratio was 22.0 for plasma viral load > or = 100,000 copies/ml compared with the reference group of < 100 000 copies/ml (Fisher's exact test, P = 0.016). The CD4 cell count and CD4/CD8 of the transmitted group were significantly lower than that of the nontransmitted (t = 2.767, P < 0.05; t = 6.06, P < 0.05).</p><p><b>CONCLUSIONS</b>The frequencies of heterosexual-transmission in central China were relatively low. The risk of heterosexual transmission was related to the frequency of sexual intercourse. Higher plasma viral load and lower CD4 count was strongly correlated with high risk of heterosexual transmission.</p>