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On January 25, 2017, a physician from ZC Hospital in Hangzhou, China, reported to the Zhejiang Provincial Center for Disease Control and Prevention that a potential HIV outbreak might have occurred during lymphocyte immunotherapy (LIT) performed at the hospital on December 30, 2016. We immediately began investigating and identified the index case-patient as an LIT patient’s husband who donated lymphocytes for his wife’s LIT and later screened HIV-reactive. Subsequent contamination by a technician resulted in the potential exposure of 34 LIT patients. Acute HIV infection was diagnosed in 5 persons. Phylogenetic analysis confirmed that the HIV-1 gag, pol, and env gene sequences from the index and outbreak-related cases had >99.5% similarity. Rapid investigation and implementation of effective control measures successfully controlled the outbreak. This incident provides evidence of a lapse in infection control causing HIV transmission, highlighting the need for stronger measures to protect patients from infectious disease exposure.

BACKGROUND:Measures to effectively expand tracing and testing to identify undiagnosed HIV infections are significant for the control of HIV/AIDS epidemic among men who have sex with men (MSM). We piloted a choice-based tracing and testing package aimed at improving partner tracing, uptake, and yield of HIV testing for sexual partners of newly diagnosed HIV-positive MSM. METHODS:This package was piloted in the cities of Hangzhou and Ningbo, Zhejiang province, China from June 2014 to June 2016. The package adopted four modes: couples' HIV counseling and testing (CHCT), information assisted partner notification (IAPN), assisted HIV self-testing (HIVST) and patient referral. Data regarding sociodemographic factors and sexual behaviors between HIV-positive MSM and their sexual partners, as well as tracing and testing outcomes of each mode, were collected. RESULTS:Among 2,495 newly diagnosed HIV-positive MSM, 446(18%) were enrolled as index cases (ICs) through two rounds of contact tracing. The ICs disclosed a total of 4,716 sexual partners, of whom 548 (12%) were reachable. The pilot study resulted in a testing uptake of 87% (478/548), and a yield of 16% (74/478) among sexual partners. The generalized linear mixed model showed that the odds of a reachable sexual partner enrolled via IAPN taking an HIV test were 290% greater than that of a partner traced via CHCT (95% CI: 1.6, 9.3). CONCLUSIONS:A choice-based tracing and testing package can feasibly expand HIV testing uptake and case finding among sexual partners of HIV-positive MSM. IAPN may be an acceptable option to reach sexual partners for whom limited contact information is available.

Abstract Background Previous studies have shown that the increased coverage of antiretroviral therapy (ART) could reduce the community viral load (CVL) and reduce the occurrence of new HIV infections. However, the impact on the reduction of HIV transmission among men who have sex with men (MSM) is much less certain. The frequency of HIV infections in MSM have been rapidly increasing in recent years in Hangzhou, China. The “Treatment as Prevention” strategy was implemented at a population-level for HIV-infected MSM from January 2014 to June 2016 in Hangzhou; it aimed to increase the ART coverage, reduce the CVL, and reduce HIV transmission. Methods We investigated a subset of MSM diagnosed with HIV pre- and post-implementation of the strategy, using random sampling methods. Viral load (VL) testing was performed for all enrolled individuals; the lower limits of detection were 20 and 50 copies/mL. The data on infections were collected from the national epidemiology database of Hangzhou. Logistic regression analyses were conducted to identify factors associated with the differences in social demographic characteristics and available VL data. Results The ART coverage increased from 60.7% (839/1383) during the pre-implementation period to 92.3% (2183/2365) during the post-implementation period in Hangzhou. A total of 940 HIV-infected MSM were selected for inclusion in this study: 490 (52.1%) and 450 (47.9%) MSM in the pre- and post-implementation periods, respectively. In total, 89.5% (841/940) of patients had data available on VL rates. The mean CVL was 579 copies/mL pre-implementation and this decreased to 33 copies/mL post-implementation (Kruskal-Wallis

Abstract Background Men who have sex with men (MSM) have become one of high-risk population for human immunodeficiency virus (HIV) infection, due to their multiple sex partners and unprotected anal intercourse. Promoting HIV testing is an effective strategy for the prevention and control of HIV infection. We assessed the factors associated with a prior HIV testing history, which could provide guidance for implementation of future HIV intervention programs. Methods A cross-sectional study was conducted in three cities of Zhejiang Province, namely, Hangzhou, Ningbo and Wenzhou, using respondent-driven sampling, between December 2013 and June 2014. A face-to-face questionnaire survey was employed to collect relevant information about HIV testing. Univariate and multivariate logistic regression analyses were used to identify the factors associated with a prior HIV testing history. Results The adjusted rate of prior HIV testing among MSM in Zhejiang Province was 55.9 %. The adjusted rates of HIV and syphilis infections among MSM in Zhejiang Province were 14.0 % and 11.4 %, respectively. A weighted multivariate analysis showed that MSM of older age were more likely to be tested, as were MSM with higher level of education, self-reported homosexuality and a higher frequency of receiving AIDS/sexually transmitted infections educational intervention in the past year. MSM with suicidal inclination and self-perceived lower possibility of HIV infection were less likely to report ever having undergone an HIV test. Conclusions The prevalence of prior HIV testing among MSM in Zhejiang Province, China is low. Effective and more frequent interventional measures should be adopted to improve risk awareness and psychosocial support for younger, less educated MSM, and to encourage more MSM to undergo HIV testing.

Men who have sex with men (MSM) are a large high-risk population for HIV infection in recent years in China. A cross-sectional survey was conducted in Hangzhou, China, to determine rates of condomless anal intercourse (CAI), recent HIV testing (in the recent year) and associated factors using respondent-driven sampling. Questionnaires using face-to-face interviews were employed to collect data on sexual risk behaviors and HIV testing. Five hundred eleven MSM were recruited, of which 459 (89.8%) had anal intercourse in the past 6 months. Of these 459 participants, 457 (99.6%) answered whether they had taken an HIV test in the recent year, so only their data were analyzed. Weighted data were analyzed using bivariate and multivariate logistic regression analysis. The CAI rate with male partners in the past 6 months was 43.7% (95% confidence interval [CI], 34.0-51.5%), while the rate of condomless vaginal intercourse (CVI) was 21.6% (95% CI, 15.6-32.3%). The prevalence of recent HIV testing was 56.8% (95% CI, 48.7-66.5%), while the prevalence of HIV and syphilis were 8.8% and 6.5%, respectively. Multivariate analysis indicated that CAI was associated with earlier homosexual debut, suicidal inclinations, childhood sexual abuse, HIV testing in the recent year, and lower estimate of HIV prevalence. Recent HIV testing was associated with homosexual debut age, engaging in CAI with male partners in the past 6 months, having oral sex in the past 6 months, self-perceived higher likelihood of HIV infection, knowing about antiretroviral therapy for HIV/AIDS, receiving AIDS/sexually transmitted infection (STI) interventions in the past year, and syphilis infection. Given high prevalence of HIV and syphilis, high levels of CAI and CVI, and low HIV testing rate, the results indicated high risk of HIV infection and transmission among MSM. HIV prevention interventions should target MSM with early homosexual debut and psychosocial health problems, while HIV/AIDS education among MSM should focus on increasing knowledge of HIV risk, estimated HIV prevalence and antiretroviral therapy, and improving risk perception of HIV acquisition.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease in China and case-fatality rate of SFTS is very high (approximately 10%). However, genetic susceptibility for SFTS virus (SFTSV) infection and fatal outcome of SFTSV infection in humans are unclear. In this study, we investigated the clinical, laboratory and epidemiological features of SFTS in a cluster of three sisters who died of SFTSV infection between late April and mid-May 2014. Before disease onset, two of the sisters (Case A and case B) had common exposure history for ticks by working together in a field to pick tea leaves from April 8 to April 12. The third sister (Case C) did not live or work together with case A and B, but had ticks in her living environment. SFTSV RNA sequences were amplified from three cases were not identical, suggesting that the three sisters were most likely infected with SFTSV through tick bite rather than through person-to-person transmission of SFTSV. The sequence of SFTSV from case C was identical to SFTSV sequences from 3 groups of ticks collected around the residential area of case C. Seroprevalence of SFTSV IgG antibody among healthy population in the area where the patients resided was 4.05% (3/74). The majority of SFTSV infections were mild cases and all three sisters died of SFTSV infection suggested that they were highly susceptible to SFTSV. Our findings indicated that genetic susceptibility was a risk factor for SFTSV infection and fatal outcome.

BACKGROUND: Human infection with a novel avian-origin influenza A (H7N9) virus occurred continuously in China during the first half of 2013, with high infectivity and pathogenicity to humans. In this study, we investigated the origin of internal genes of the novel H7N9 virus and analyzed the relationship between internal genes and infectivity of the virus. METHODOLOGY AND PRINCIPAL FINDINGS: We tested the environmental specimens using real-time RT-PCR assays and isolated five H9N2 viruses from specimens that were positive for both H7 and H9. Results of recombination and phylogeny analysis, performed based on the entire sequences of 221 influenza viruses, showed that one of the Zhejiang avian H9N2 isolates, A/environment/Zhejiang/16/2013, shared the highest identities on the internal genes with the novel H7N9 virus A/Anhui/1/2013, ranging from 98.98% to 100%. Zhejiang avian H9N2 isolates were all reassortant viruses, by acquiring NS gene from A/chicken/Dawang/1/2011-like viruses and other five internal genes from A/brambling/Beijing/16/2012-like viruses. Compared to A/Anhui/1/2013 (H7N9), the homology on the NS gene was 99.16% with A/chicken/Dawang/1/2011, whereas only 94.27-97.61% with A/bramnling/Beijing/16/2012-like viruses. Analysis on the relationship between internal genes and the infectivity of novel H7N9 viruses were performed by comparing amino acid sequences with the HPAI H5N1 viruses, the H9N2 and the earlier H7N9 avian influenza viruses. There were nine amino acids on the internal genes found to be possibly associated with the infectivity of the novel H7N9 viruses. CONCLUSIONS: These findings indicate that the internal genes, sharing the highest similarities with A/environment/Zhejiang/16/2013-like (H9N2) viruses, may affect the infectivity of the novel H7N9 viruses.

BACKGROUND: While human cases of highly pathogenic avian influenza A (H5N1) virus infection continue to increase globally, available clinical data on H5N1 cases are limited. We conducted a retrospective study of 26 confirmed human H5N1 cases identified through surveillance in China from October 2005 through April 2008. METHODOLOGY/PRINCIPAL FINDINGS: Data were collected from hospital medical records of H5N1 cases and analyzed. The median age was 29 years (range 6-62) and 58% were female. Many H5N1 cases reported fever (92%) and cough (58%) at illness onset, and had lower respiratory findings of tachypnea and dyspnea at admission. All cases progressed rapidly to bilateral pneumonia. Clinical complications included acute respiratory distress syndrome (ARDS, 81%), cardiac failure (50%), elevated aminotransaminases (43%), and renal dysfunction (17%). Fatal cases had a lower median nadir platelet count (64.5 x 10(9) cells/L vs 93.0 x 10(9) cells/L, p = 0.02), higher median peak lactic dehydrogenase (LDH) level (1982.5 U/L vs 1230.0 U/L, p = 0.001), higher percentage of ARDS (94% [n = 16] vs 56% [n = 5], p = 0.034) and more frequent cardiac failure (71% [n = 12] vs 11% [n = 1], p = 0.011) than nonfatal cases. A higher proportion of patients who received antiviral drugs survived compared to untreated (67% [8/12] vs 7% [1/14], p = 0.003). CONCLUSIONS/SIGNIFICANCE: The clinical course of Chinese H5N1 cases is characterized by fever and cough initially, with rapid progression to lower respiratory disease. Decreased platelet count, elevated LDH level, ARDS and cardiac failure were associated with fatal outcomes. Clinical management of H5N1 cases should be standardized in China to include early antiviral treatment for suspected H5N1 cases.

The half-open multi-depot vehicle routing problem (HOMDVRP) is a typical decision optimization problem in the field of collaborative logistics that considers resource sharing. This study aims to develop an effective meta-heuristic algorithm for solving the HOMDVRP. Firstly, a mixed-integer programming model of HOMDVRP is established to minimize the total travel distance of the vehicles. After that, a novel hybrid adaptive simulated annealing and tempering algorithm (HASATA) is proposed based on the features of HOMDVRP. The proposed algorithm combines the strengths of the simulated annealing algorithm and the large-neighborhood search algorithm to balance the algorithm’s searching capabilities in both breadth and depth. Meanwhile, an adaptive Markov chain length mechanism and a tempering mechanism are designed to improve the algorithm’s computational efficiency and convergence ability. Finally, simulation experiments are conducted to verify the effectiveness of the proposed model and the computational performance of the proposed algorithm. Four comparison algorithms are selected and analyzed using 24 groups of problem instances. The comparison results show that the proposed HASATA can solve the HOMDVRP more efficiently and obtain a solution with better optimization performance and satisfactory stability.

Automatic guided vehicles (AGVs) in the horizontal area play a crucial role in determining the operational efficiency of automated container terminals (ACTs). To improve the operational efficiency of an ACT, it is essential to decrease the impact of battery capacity limitations on AGV scheduling. To address this problem, this paper introduces battery swapping and opportunity charging modes into the AGV system and proposes a new AGV scheduling problem considering the hybrid mode. Firstly, this study describes the AGV scheduling problem of the automated container terminals considering both loading and unloading tasks under the hybrid mode of battery swapping and charging. Thereafter, a mixed-integer programming model is established to minimize the sum of energy costs and delay costs. Secondly, an effective adaptive large neighborhood search algorithm is proposed to solve the problem, in which the initial solution construction, destroy operators, and repair operators are designed according to the hybrid mode. Finally, numerical experiments are conducted to analyze the effectiveness of the model and the optimization performance of the algorithm. The results demonstrate that the hybrid mode of battery swapping and charging can effectively reduce the number of battery swapping times and scheduling costs compared to the existing mode.

This paper addresses the robust job-shop scheduling problems (RJSSP) with stochastic deteriorating processing times by considering the resilience of the production schedule. To deal with the disturbances caused by the processing time variations, the expected deviation between the realized makespan and the initial makespan is adopted to measure the robustness of a schedule. A surrogate model for robust scheduling is proposed, which can optimize both the schedule performance and robustness of RJSSP. Specifically, the computational burden of simulation is considered a deficiency for robustness evaluation under the disturbance of stochastic processing times. Therefore, a resilience-based surrogate robustness measure (SRM-R) is provided for the robustness estimation in the surrogate model. The proposed SRM-R considers the production resilience and can utilize the available information on stochastic deteriorating processing times and slack times in the schedule structure by analyzing the disturbance propagation of the correlated operations in the schedule. Finally, a multi-objective hybrid estimation of distribution algorithm is employed to obtain the Pareto optimal solutions of RJSSP. The simulation experiment results show that the presented SRM-R is effective and can provide the Pareto solutions with a lower computational burden. Furthermore, an RJSSP case derived from the manufacturing environment demonstrates that the proposed approach can generate satisfactory robust solutions with significantly improved computational efficiency.