ObjectiveTo investigate a cluster epidemic of coronavirus disease 2019 （COVID-19） infections in a school in Longchuan County， Yunnan Province， and further guide the prevention and control of COVID-19 in the border area. MethodsAccording to the Protocol on Prevention and Control of Novel Coronavirus Pneumonia （8th Edition）， an epidemiological investigation was performed on all COVID-19 cases to collect the information on demographics， onset， diagnosis and treatment， prognosis， and epidemiological history. Close contacts were also tracked to determine the transmission chains. ResultsIn this cluster epidemic， a total of 37 COVID-19 cases were identified， including 32 females and 5 males aged from 13 to 25 years， who were 35 students and 2 teachers. The student cases were found in four classes of two grades. Furthermore， gene sequencing showed that all cases had been infected with delta variants， belonging to the same transmission chain that was not related to the previous epidemics in Dehong Prefecture. In additionally， a total of 2 127 close contacts were found. After 21 days of centralized quarantine for medical observation， all close contacts tested negative for SARS-CoV-2. In the COVID-19 cases， only one case remained positive for SARS-CoV-2， while the other 36 cases were successfully treated and became negative. ConclusionThis school cluster is caused by the border villagers who contacted the water polluted with SARS-CoV-2. It warrants more strict management of students from border villages and their belongings to prevent similar epidemics in school settings.

Objective:To investigate the distributions of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) genotypes among newly reported HIV/HCV co-infected Burmese patients in Dehong Dai and Jingpo Autonomous Prefecture, Yunnan Province from 2016 to 2019.Methods:A total of 1 289 newly reported HIV/HCV co-infected Burmese patients in Dehong Dai and Jingpo Autonomous Prefecture were collected through the National Acquired Immunodeficiency Syndrome Comprehensive Prevention and Control Data Information System From January 2016 to December 2019. Among them, 996 subjects with a plasma volume of ≥200 μL were selected to perform HIV and HCV genotyping. The HIV pol gene, the HCV core protein-binding envelope protein ( CE1) gene and non-structural protein 5B ( NS5 B) gene were amplified using the nested polymerase chain reaction.The phylogenetic tree was constructed by MEGA 7.0 software to classify the genotypes. Chi-square test was used for statistical analysis. Trend chi-square test was used to analyze the trend of HIV and HCV genotypes. Results:Among the 996 cases with HIV/HCV co-infection, HIV and HCV sequences from a total of 554 subjects (55.6%, 554/996) were successfully obtained, and the genotypes of HIV and HCV were diverse. HIV genotype C (40.3%, 223/554) and BC recombinant (33.6%, 186/554) were the most prevalent, followed by genotype B (6.5%, 36/554) and circulating recombinant form (CRF)01_AE (3.6%, 20/554). HCV genotype 3b was the most prevalent (31.2%, 173/554), followed by genotype 6u (19.5%, 108/554), 1a (17.5%, 97/554), 6n (11.4%, 63/554), 3a (8.7%, 48/554) and 6xg (6.3%, 35/554). The prevalence of HIV genotype C showed a downward trend ( χtrend2=7.23, P<0.001), while the prevalence of BC recombinant showed an upward trend ( χtrend2=5.97, P<0.001), and the proportion of BC recombinant was higher than genotype C in 2019 (54.9%(101/184) vs 21.7%(40/184)). However, there were no statistically significant differences in the proportions of genotype 3b, 6u and 1a from 2016 to 2019 ( χtrend2=1.43, 1.79 and 0.39, respectively, P=0.152, 0.074 and 0.695, respectively). The HIV genotype distribution among patients with different ethnic groups were significantly different ( χ2=22.06, P=0.037). Conclusions:The diversity of HIV and HCV genotypes is high and complex among HIV/HCV co-infected Burmese patients in Dehong Dai and Jingpo Autonomous Prefecture. BC recombinant shows a trend of becoming the predominant HIV genotype among these co-infected patients. Therefore, surveillance of the prevalence of HCV and HIV genotypes in Burmese population needs to be further strengthened.

Objective:To explore the changing trends and influencing factors of AIDS-related and non-AIDS-related deaths after receiving antiretroviral therapy (ART) among HIV-positive individuals in Dehong Dai Jingpo autonomous prefecture (Dehong) from 2010 to 2019.Methods:Based on the Chinese National treatment database, HIV patients who initiated ART from 2010 to 2019 were included in the analysis. The cumulative incidence function was used to estimate the cumulative incidence of AIDS-related death and non-AIDS-related death, respectively. The Fine-Grey model was used to compare the differences between AIDS-related and non-AIDS-related deaths and analyze its influencing factors.Results:A total of 7 068 HIV-positive individuals were included, of which 388 were AIDS-related deaths and 570 were non-AIDS-related deaths. The cumulative mortality rate at years 1, 2, 3, 4, 5, 7 and 9 after receiving ART were 2.27%, 3.46%, 4.47%, 5.03%, 5.84%, 6.61%, 7.40% for AIDS-related deaths, and 1.63%, 3.11%, 4.68%, 6.02%, 7.42%, 10.49%, 12.75% for non-AIDS-related deaths, respectively. In the Fine-Grey model, older age at ART initiation, male, unmarried, injection drug use as the transmission route, lower baseline BMI, lower baseline CD4 + T cell counts, baseline FIB-4 score >3.25, and baseline anemia were risk factors for AIDS-related death. In contrast, age at ART initiation ≥45 years, male, Dai, and Jingpo minority ethnicities, unmarried, injection drug use as the transmission route, lower baseline BMI, baseline FIB-4 score >3.25, baseline eGFR <60 ml·min -1·1.73 m -2, and baseline anemia were risk factors for non-AIDS-related deaths. Conclusions:The cumulative mortality rate was low among HIV-positive individuals after receiving ART in Dehong during 2010-2019. The mortality of non-AIDS-related deaths was higher than that of AIDS-related deaths. There were also differences in the factors influencing AIDS-related and non-AIDS-related deaths and interventions should be intensified to target the influencing factors for non-AIDS-related deaths.

Objective:To study the prevalence and correlations of HIV infection among cross-border couples in the Dehong prefecture.Methods:A cross-sectional mass screening study with questionnaire interview and HIV testing was conducted among 17 594 registered cross-border couples from May 2017 through June 2018.Results:Among 32 400 participants, the overall prevalence of HIV infection was 2.27% (736/32 400), 2.44% (375/15 372) for Chinese citizens, and 2.12% (361/17 028) for foreign spouses. Among all the 13 853 couples with both spouses receiving HIV testing, 13 415(96.84%) were seroconcordant-negative couples, 142(1.03%) were serocondordant-positive couples, and 296(2.13%) were serodiscordant couples, including 167(1.20%) couples with positive husband and negative wife and 129(0.93%) couples with positive wife and negative husband. Multiple logistic regression analyses indicated that HIV infection was associated with drug use and risky sexual behaviors for male spouses. In contrast, HIV infection was associated with risky sexual behaviors for female spouses.Conclusion:The prevalence of HIV among cross-border couples in Dehong prefecture is high, underscoring the urgent need to scale up HIV testing, prevention, and behavioral intervention.

Objective:To analyze the longitudinal characteristics of CD4 +T lymphocytes (CD4) among the adult HIV/AIDS on antiretroviral therapy (ART) and the related factors. Methods:A retrospective cohort of adult HIV/AIDS starting ART in Dehong Dai and Jingpo Autonomous Prefecture (Dehong) in 2007-2016 was followed up to December 31, 2018. Group-based trajectory models were utilized to identify CD4 subgroups based on immune recovery (whether and when CD4 reached the average level of >500 cells/μl). The demographics and information at ART baseline were described, and the related factors were analyzed with polytomous logistic regression. The SAS 9.4 software was used for statistical analysis.Results:A total of 7 605 adults with HIV/AIDS were included, of which the median ( P 25, P 75) age at ART were 36 (30,43) years old, 61.0% were male, 42.5% were Han nationality, and 60.8% with the education of primary school or below. The follow-up duration M ( P 25, P 75) was 6.1 (4.1,8.1) years. HIV/AIDS in Dehong showed four CD4 trajectory subgroups from low to high: below the average level, primary recovery to a normal level, full recovery to a moderate level, and normal steady level, accounting for 34.4%, 39.8%, 20.6%, and 5.2%, respectively. When compared with corresponding control groups, age <35 years at ART, female, education of middle school or above, sexual transmission, no opportunistic infection, CD4 ≥200 cells/μl, baseline regimen with tenofovir (TDF) and time from HIV diagnosis to ART <1 year were the related factors facilitating the higher CD4 subgroups. Conclusions:The various CD4 immune recoveries of HIV/AIDS were changing patterns after ART. Starting ART with a high CD4 level was beneficial to CD4 recovery to normal level during the follow-up period. Early initiation of ART and exceptional attention to CD4 immune recovery should be encouraged after the ART.

Objective:To investigate the incidence of anemia and risk factors in HIV/AIDS patients with access to antiretroviral therapy (ART) during 2004-2018 in Dehong Jingpo and Dai Autonomous Prefecture (Dehong).Methods:A retrospective cohort study was conducted in HIV/AIDS patients receiving ART in Dehong during 2004-2018 based on the data extracted from the National HIV/AIDS antiretroviral therapy database. Cox proportional risk model was used to analyze the factors associated with the incidences of anemia and moderate or severe anemia in the HIV/AIDS patients. And the piecewise linear mixed-effects model was used to depict the trajectory of hemoglobin changes over time after initiating ART according to baseline level.Results:A total of 8 044 HIV/AIDS patients were included, in whom 6 337 (78.8%) were without anemia at baseline survey and had a median follow up time of 4.43 ( P 25, P 75: 1.50, 6.71) years. The median follow up time for 1 291 new anemia cases and 293 new moderate or severe anemia cases was 0.16 ( P 25, P 75: 0.07, 1.99) years and 0.48 ( P 25, P 75:0.09, 2.97) years, respectively. The incidence rate of anemia and moderate or severe anemia was 4.40 per 100 person-years and 0.41 per 100 person-years respectively. In multivariable Cox regression analysis, older age, being female, being in Dai and Jingpo ethnic group, baseline BMI <18.5 kg/m 2, baseline CD4 +T lymphocyte cell counts (CD4) <200 cells/μl, and zidovudine (AZT) -based initial treatment regimen were factors significantly and positively associated with incidence of anemia after treatment. Factors as being female, being in Dai ethnic group, baseline BMI <18.5 kg/m 2, mild baseline anemia, and AZT-based initial treatment regimen were significantly and positively associated with incidence of moderate or severe anemia after treatment. Conclusion:The risk for anemia was higher in HIV/AIDS patients with specific characteristics, such as age ≥60 years , being female, being in Dai and Jingpo ethnic groups, lower BMI, CD4 <200 cells/μl, and treatment of AZT, after initiation of ART in Dehong during 2004-2018. Additional efforts are needed to strengthen the screening, prevention and treatment of anemia in this population.

Objective: To study the prevalence and correlates of diabetes among HIV/AIDS who were on antiretroviral therapy (ART) in Dehong Dai and Jingpo autonomous prefectures (Dehong), Yunnan province. Methods: The database of HIV/AIDS receiving ART in Dehong was downloaded by using the basic information system of AIDS prevention and control in China. In this cross-sectional study, HIV/AIDS patients who were currently on ART and aged 18 years or above, were consecutively recruited, between July 2017 and June 2018, in Dehong. All the subjects underwent hemoglobin A1c (HbA1c) testing. Patient with diabetes was defined as meeting any of these indicators (HbA1c ≥6.5%, baseline FPG ≥7.0 mmol/L, FPG ≥7.0 mmol/L in the most recent visit). Both univariate and multivariate logistic regression analysis were carried on to evaluate the correlates of diabetes among the HIV/AIDS patients. Results: In total of 4 376 HIV/AIDS patients were included for analysis, with the average age as (43.7±10.1) years, proportion of males as 53.8% (2 356/4 376) and the HCV positive rate as 24.1% (1 055/4 376). The mean years was (8.9±3.8) years after the HIV diagnosis was made, and the mean duration on treatment was (6.8±2.9) years. The prevalence of diabetes was 11.4% (500/4 376). Through multivariate logistic regression analysis, data showed that the risk factors of diabetes of HIV/AIDS on ART were: aged 40 years or above, being male, HCV positive, baseline body mass index ≥24.0 kg/m², elevated TG ≥1.70 mmol/L in the most recent visit and baseline antiretroviral regimens under Efavirenz (EFV). Conclusions Prevalence rate of diabetes appeared higher in HIV/AIDS patients who were on ART in Dehong. Prevention and control measures should be targeted on HIV/AIDS patients who were with risk factors of diabetes as being elderly, male, HCV positive, overweight and higher TG. Further esearch is needed to evaluate the association between the use of EFV and diabetes.

Objective: To understand the distribution of HIV-1 genotypes and the status of drug resistance among people living with HIV who had prepared to initiate antiretroviral therapy (ART) in Dehong Dai and Jingpo autonomous prefecture (Dehong). Methods: A total of 170 adults with HIV were recruited in Dehong from January to June 2017, before initiating ART. HIV-1 pol genes were amplified and used to analyze the HIV-1 genotypes and drug resistance. Results: A total of 147 samples were successfully sequenced. Based on the phylogenetic analysis, 12 HIV-1 genotypes were found among the subjects, including three predominant genotypes such as subtype C (29.9%, 44/147), unique recombinant forms (URFs) (27.2%, 40/147) and CRF01_AE (19.7%, 29/147). Circulating recombinant forms (CRFs) which were newly identified in this area in recent years were also found among these subjects, including CRF62_BC, CRF64_BC, CRF86_BC and CRF96_cpx. The distribution of HIV-1 genotypes between heterosexual transmission or intravenous drug use, showed statistical difference. Surveillance drug resistance mutations (SDRMs) were found among 8.8% (13/147) of the subjects. Proportion of drug resistant strains among injecting drug users (25.0%, 8/32) was higher than that among those heterosexual transmitted individuals (4.6%, 5/109, χ²=10.166, P=0.002). Conclusions Among people living with HIV-1 who had prepared to initiate ART, their HIV-1 genetics were highly complicated, with moderate prevalence rate of HIV-1 drug-resistant strains.

Objective: To obtain HIV incidence among injection drug users (IDU) and female sex workers (FSW) in Dehong Prefecture, Yunnan Province during 2009-2017. Methods: We recruited drug users and female sex workers from all sentinel surveillance sites across Dehong Prefecture during 2009-2017. A total of 10 480 IDU and 18 126 FSW in Dehong Prefecture were recruited by fingerprint technique. Data about drug uses, commercial sexual behavior, sociodemographic characteristics was collected by structured questionnaire. HIV-positive patients who were long-term infected or with CD4⁺ T cell count was ≤200 were not included for further HIV incidence testing. Also, those who self-identified as on antiretroviral treatment (ART) or AIDS cases were also excluded. A total of 841 and 157 plasma specimens from IDU and FSW that met the inclusion criterion were finally included, respectively. Limiting antigen avidity enzyme immunoassay(LAg-Avidity EIA) were performed to calculate the HIV incidence among these two sub-populations. Results: A total of 3 444 IDU were HIV-positive, among which 884 (25.7%) were Burmese with age of (30.4±7.7), and 2 560 were Chinese with age of (36.6±7.3). Among 228 HIV-positive FSW, 109 (47.8%) were Burmese with age of (27.1±6.3), 119 (52.5%) were Chinese with age of (29.9±11.1). For IDU, the estimated HIV incidence among Burmese in 2009-2010, 2011-2012, 2013-2014, 2015-2017 was 4.20% (95%CI: -0.55%-8.95%), 7.75% (95%CI: 2.95%-12.55%), 11.79% (95%CI: 5.38%-18.20%), 10.30% (95%CI: 5.67%-14.94%), respectively, while Chinese were 3.11% (95%CI: 1.59%-4.64%), 0.03% (95%CI: -0.03%-0.08%), 1.55% (95%CI: 0.54%-2.57%), 0.58% (95%CI: -0.06%-1.04%), respectively. In 2009-2011, 2012-2014, 2015-2017, estimated HIV incidence among Burmese FSW was 0.22% (95%CI: -0.21%-0.64%), 1.24%(95%CI: 0.15%-2.32%), 0.55%(95%CI: 0.01%-1.08%). Whereas, estimated HIV incidence among Chinese FSW was 0.62% (95%CI: 0.25%-0.98%), 0.11% (95%CI: -0.04%-0.26%), 0.22% (95%CI: 0-0.44%). Conclusion HIV incidences among Chinese IDU and FSW are on the downward trend, while Burmese IDU and FSW seem to be gaining momentum.

Objective: To study the prevalence and correlates of unprotected sexual intercourse within HIV serodiscordant couples in Dehong prefecture, Yunnan Province, China, in 2014. Methods: This study was based on the follow-up investigation of "the AIDS cohort of seronegative spouses of HIV-infected individuals in Dehong prefecture" in 2014. The 1 520 participants were HIV seronegative spouses from all five counties/cities of Dehong prefecture who voluntarily participated in the cohort. Inclusion criteria included: having a HIV-positive spouse; ≥16 years of age; having had sexual intercourse with spouse in the past year; and being a resident of Dehong prefecture. Information on HIV-positive spouses were also collected through the local AIDS epidemic database. Chi square analysis was performed to compare differences in the rates of unprotected sexual intercourse between participants with different characteristics and lifestyle choices. Multivariable logistic regression model analysis was performed to determine correlates with unprotected sexual intercourse. Results: The 1 520 participants had a mean age of 38.7±9.4, compared with 39.7±8.9 for their HIV-positive spouses. Among the HIV-positive spouses, 77.8% (1 183/1 520) had been infected for more than 3 years, and 87.6% (1 332/1 520) had received antiretroviral therapy. The prevalence of unprotected sexual intercourse within serodiscordant couples over the past 12 months was 16.1% (244/1 520). The prevalence of unprotected sexual intercourse correlated with the level of education of HIV-negative spouses (illiterate vs. middle school and above, OR=1.58, P=0.044), the number of years since diagnosis of HIV-positive spouses (short vs. long, OR=1.6, P=0.006), antiretroviral therapy of HIV-positive spouses (no vs. yes, OR=2.78, P<0.001), the frequency of sexual intercourse per month (high vs. low, OR=1.66, P=0.019), and whether the couple had children (no vs. yes, OR=1.72, P=0.007). Conclusion The prevalence of unprotected sexual intercourse within serodiscordant couples in Dehong prefecture was relatively high in 2014. Factors found to correlate with the occurrence of unprotected sexual intercourse within these couples included illiteracy of HIV-negative spouses, short time since diagnosis of HIV-positive spouses and lack of antiretroviral therapy, high frequency of sexual intercourse and no children.