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BACKGROUND: The first local outbreak of Delta Variant B.1.617.2 COVID-19 of China occurred in Guangzhou city, south China, in May 2021. This study analyzed the transmission chains and local cluster characteristics of this outbreak, intended to provide information support for the development and adjustment of local prevention and control strategies. METHODS: The transmission chains and local cluster characteristics of 161 local cases in the outbreak were described and analyzed. Incubation period, serial interval and generation time were calculated using the exact time of exposure and symptom onset date of the cases. The daily number of reported cases and the estimated generation time were used to estimate the effective reproduction number (Rt). RESULTS: We identified 7 superspreading events who had more than 5 next generation cases and their infected cases infected 70.81%(114/161) of all the cases transmission. Dining and family exposure were the main transmission routes in the outbreak, with 29.19% exposed through dining and 32.30% exposed through family places. Through further analysis of the outbreak, the estimated mean incubation period was 4.22 (95%CI: 3.66-4.94) days, the estimated mean generation time was 2.60 (95%CI: 1.96-3.11) days, and the estimated Rt was 3.29 (95%CI: 2.25-5.07). CONCLUSIONS: Classification and dynamically adjusted prevention and control measures had been carried out according to analysis of transmission chains and epidemical risk levels, including promoting nucleic acid screening at different regions and different risk levels, dividing closed-off area, controlled area according to the risk of infection, raising the requirements of leaving Guangzhou. By the above control measures, Guangzhou effectively control the outbreak within 28 days without implementing a large-scale lockdown policy.
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COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2/genética , Control de Enfermedades Transmisibles , Brotes de Enfermedades , China/epidemiologíaRESUMEN
OBJECTIVES: Scrub typhus is an increasingly serious public health problem, which is becoming the most common vector-borne disease in Guangzhou. This study aimed to analyse the correlation between scrub typhus incidence and potential factors and rank the importance of influential factors. METHODS: We collected monthly scrub typhus cases, meteorological variables, rodent density (RD), Normalised Difference Vegetation Index (NDVI), and land use type in Guangzhou from 2006 to 2019. Correlation analysis and a random forest model were used to identify the risk factors for scrub typhus and predict the importance rank of influencing factors related to scrub typhus incidence. RESULTS: The epidemiological results of the scrub typhus cases in Guangzhou between 2006 and 2019 showed that the incidence rate was on the rise. The results of correlation analysis revealed that a positive relationship between scrub typhus incidence and meteorological factors of mean temperature (Tmean ), accumulative rainfall (RF), relative humidity (RH), sunshine hours (SH), and NDVI, RD, population density, and green land coverage area (all p < 0.001). Additionally, we tested the relationship between the incidence of scrub typhus and the lagging meteorological factors through cross-correlation function, and found that incidence was positively correlated with 1-month lag Tmean , 2-month lag RF, 2-month lag RH, and 6-month lag SH (all p < 0.001). Based on the random forest model, we found that the Tmean was the most important predictor among the influential factors, followed by NDVI. CONCLUSIONS: Meteorological factors, NDVI, RD, and land use type jointly affect the incidence of scrub typhus in Guangzhou. Our results provide a better understanding of the influential factors correlated with scrub typus, which can improve our capacity for biological monitoring and help public health authorities to formulate disease control strategies.
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Tifus por Ácaros , Humanos , Tifus por Ácaros/epidemiología , Bosques Aleatorios , Temperatura , China/epidemiología , Factores de Riesgo , IncidenciaRESUMEN
BACKGROUND: Malaria was once widespread in Guangzhou, China. However, a series of control measures have succeeded in eliminating local malaria infections. Based on the analysis of the characteristics of malaria epidemics in Guangzhou, China, from 1950 to 2022, the changes and effectiveness of malaria control strategies and surveillance management in Guangzhou from 1950 to 2022 are described. METHODS: Data on malaria prevention and treatment in Guangzhou from 1950 to 2022 were collected, and descriptive epidemiological methods were used to analyse the prevalence of malaria, preventive and control measures taken, and the effectiveness of prevention and treatment in different periods. Data on malaria cases were obtained from the Guangzhou Centre for Disease Control and Prevention (CDC) and the China Communicable Disease Reporting System. RESULTS: The development of the malaria control system in Guangzhou has gone through four periods: 1. High malaria prevalence (1950-1979), 2. Intensive prevention and control stage (1980-2000), 3. Consolidating gains in malaria control (2001-2008), and 4. Preventing reestablishment of transmission (2009-2022). During Period 1, only medical institutions at all levels and the local CDCs, the Guangzhou CDC participated in the malaria prevention and control system, establishing a three-tier health system on malaria prevention and control. During Period 2, other types of organizations, including the agricultural sector, schools and village committees, the construction department and street committee, are involved in the malaria control system. During Period 3, more and more organizations are joining forces to prevent and control malaria. A well-established multisectoral malaria control mechanism and an improved post-elimination surveillance management system are in place. Between 1950 and 2022, a total of 420,670 cases of malaria were reported. During Period 1, there was an epidemic of malaria in the early 1950s, with an annual incidence rate of more than 10,000/100,000, including a high rate of 2887.98/100,000 in 1954. In Period 2 malaria was gradually brought under control, with the average annual malaria incidence rate dropping to 3.14/100,000. During Period 3, the incidence rate was kept below 1/100,000, and by 2009 local malaria infections were eliminated. CONCLUSION: For decades, Guangzhou has adopted different malaria control strategies and measures at different epidemic stages. Increased collaboration among civil organizations in Guangzhou in malaria control has led to a significant decline in the number of malaria cases and the elimination of indigenous malaria infections by 2009.The experience of Guangzhou can guide the development of malaria control strategies in other cities experiencing similar malaria epidemics.
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Epidemias , Malaria , Humanos , Agricultura , China/epidemiología , Ciudades , Malaria/epidemiología , Malaria/prevención & controlRESUMEN
In this paper, a core-shell based on the Fe3O4@SiO2@Au nanoparticle amplification technique for a surface plasmon resonance (SPR) sensor is proposed. Fe3O4@SiO2@AuNPs were used not only to amplify SPR signals, but also to rapidly separate and enrich T-2 toxin via an external magnetic field. We detected T-2 toxin using the direct competition method in order to evaluate the amplification effect of Fe3O4@SiO2@AuNPs. A T-2 toxin-protein conjugate (T2-OVA) immobilized on the surface of 3-mercaptopropionic acid-modified sensing film competed with T-2 toxin to combine with the T-2 toxin antibody-Fe3O4@SiO2@AuNPs conjugates (mAb-Fe3O4@SiO2@AuNPs) as signal amplification elements. With the decrease in T-2 toxin concentration, the SPR signal gradually increased. In other words, the SPR response was inversely proportional to T-2 toxin. The results showed that there was a good linear relationship in the range of 1 ng/mL~100 ng/mL, and the limit of detection was 0.57 ng/mL. This work also provides a new possibility to improve the sensitivity of SPR biosensors in the detection of small molecules and in disease diagnosis.
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Técnicas Biosensibles , Nanopartículas del Metal , Toxina T-2 , Resonancia por Plasmón de Superficie/métodos , Oro , Dióxido de Silicio , AnticuerposRESUMEN
BACKGROUND: We estimated the predictive effects of ART-related perceptions on the actual ART uptake behavior among ART naïve PLWH stratified by different time of HIV diagnosis under the new strategy. METHODS: A prospective cohort study was conducted among ART naïve PLWH in Guangzhou, China from June 2016 to June 2017. Cox regression model was used to evaluate the predictive effects of ART-related perceptions on ART initiation among PLWH stratified by different timepoint of HIV diagnosis (i.e., before or after the update of the new treatment policy). RESULTS: Among 411 participants, 150 and 261 were diagnosed before (pre-scaleup group) and after (post-scaleup group) the implementation of the new strategy, respectively. The ART initiation rate in the post-scaleup group (88.9%) was higher than that in the pre-scaleup group (73.3%) (p < 0.001). A significant difference of mean score was detected in each HBM construct between pre- and post-scaleup groups (p < 0.05). After adjusting for significant background variables, among all participants, only the self-efficacy [adjusted HR (HRa) = 1.23, 95% CI 1.06 to 1.43, p = 0.006], has a predictive effect on ART initiation; in pre-scaleup group, all constructs of HBM-related ART perceptions were predictors of ART initiation (HRa = 0.71 to 1.83, p < 0.05), while in post-scaleup group, no significant difference was found in each construct (p > 0.05). CONCLUSIONS: The ART initiation rate was high particularly among participants who diagnosed after the new treatment strategy. The important role of the time of HIV diagnosis on ART initiation identified in this study suggested that future implementation interventions may consider to modify the ART-related perceptions for HIV patients who diagnosed before the implementation of the new ART strategy, while expand the accessibility of ART service for those who diagnosed after the implementation of the new strategy.
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Infecciones por VIH , Terapia Antirretroviral Altamente Activa , China/epidemiología , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Modelos de Riesgos Proporcionales , Estudios ProspectivosRESUMEN
BACKGROUND: The early initiation of antiretroviral therapy (ART) for people living with HIV (PLWH) benefits both individuals and societies. However, little is known about the intention to initiate ART among PLWH in China in the context of a scaling-up of treatment or how the recommendations of healthcare workers affect this intention. METHODS: A total of 451 ART-naïve PLWH were recruited from communities in Guangzhou, China for this study. Data were collected by trained physicians via face-to-face interviews. Logistic regression models were fitted for the data analyses. RESULTS: Of the participants, 93.8% were male, 72.7% were infected via homosexual behaviour and 68.5% reported an intention to initiate ART. In the latter category, 77.8, 41.9 and 20.0% of respondents received strong recommendations to initiate ART from healthcare workers at the Centres for Disease Control and Prevention (CDC), community healthcare centres and non-governmental organisations (NGOs), respectively. After adjusting for potential confounders, depression, anxiety and strong recommendations from healthcare workers at the CDC and NGOs correlated significantly with ART intention. In the adjusted final hierarchical logistic regression model, the duration of infection [multivariate odds ratio (ORm) = 0.30, p < 0.001], route of HIV infection (ORm = 0.18, p < 0.01), infection status of the current spouse/regular sex partner (ORm = 0.21-0.23, p < 0.01), anxiety (ORm = 2.44-2.65, p < 0.05) and strong recommendations from CDC physicians (ORm = 3.67, p < 0.01) or NGOs workers (ORm = 3.67, p < 0.01) were independently associated with the ART intention, whereas a recommendation from a community healthcare centre physician was not. CONCLUSIONS: In Guangzhou, the prevalence of ART intention was below the 90-90-90 targets. Further studies aimed at an in-depth understanding and encouragement of health care workers' perceptions regarding early ART are warranted as a means of scaling up new ART strategies.
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Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Personal de Salud , Intención , Aceptación de la Atención de Salud/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , China , Estudios Transversales , Femenino , Infecciones por VIH/psicología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Parejas Sexuales , Factores Socioeconómicos , Adulto JovenRESUMEN
OBJECTIVES: To investigate the impact of the Three Gorges Dam on the local ecological environment. We conducted a 3-year cross-sectional survey of natural focus infectious diseases in the area before and after the water level rose to 156 m to evaluate the dam's health impacts. METHODS: Direct and indirect immunofluorescence methods were applied to detect rat antigen and antibody of haemorrhagic fever with renal syndrome (HFRS). Fresh rat kidneys were inoculated in Korth's culture medium to detect Leptospira. A group of captured crabs were ground to observe the metacercariae of Paragonimus. Serum samples were collected from healthy local individuals. ELISA kits were used to detect human antibody against HFRS and paragonimiasis. Human Leptospira infections were detected by a microscopic agglutination test. RESULTS: Upstream rodent density increased significantly with Rattus flavipectus and Apodemus agrarius as the major pathophoric genera. The infection rate of human HFRS and Leptospira in the upstream human population samples was significantly higher than in the downstream samples and correlated with the increase in rodent density. Paragonimus infection rates remained at a low level during the study. Culex pipiens fatigan and Armigeres obturbans were the dominant species of mosquito. CONCLUSIONS: The creation of the Three Gorges Dam changed the proliferation of intermediary agents of diseases, but not notably. However, the ecological effects on the environment may require a prolonged period of time to manifest themselves; thus, long-term and effective surveillance of vectors and related diseases needs to be established.
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Vectores de Enfermedades/clasificación , Fiebre Hemorrágica con Síndrome Renal/sangre , Leptospirosis/sangre , Paragonimiasis/sangre , Ríos/microbiología , Adolescente , Adulto , Distribución por Edad , Anciano , Animales , Braquiuros , Niño , Preescolar , China/epidemiología , Culicidae , Reservorios de Enfermedades , Enfermedades Endémicas/estadística & datos numéricos , Ambiente , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente Directa/métodos , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Fiebre Hemorrágica con Síndrome Renal/epidemiología , Fiebre Hemorrágica con Síndrome Renal/inmunología , Humanos , Lactante , Leptospirosis/epidemiología , Leptospirosis/inmunología , Ratones , Persona de Mediana Edad , Paragonimiasis/epidemiología , Paragonimiasis/inmunología , Ratas , Adulto JovenRESUMEN
BACKGROUND: China experiencing an increasing HIV epidemic among men who have sex with men (MSM), and unprotected anal intercourse (UAI) has played a key role in this process. The aims of this study were to examine the trend of UAI and to explore the factors correlated with UAI among MSM in Guangzhou, China. METHODS: Data from 2008 to 2013 were retrieved from the annual serological and behavioral surveys system. We collected information on demographic, HIV related sexual behavior with men and women, access to HIV prevention services, and symptoms of sexually transmitted infections. Chi-square test was used to examine the similarity of the participants during the study period. Univariate and multivariate logistic regression were conducted to test the factors associated with UAI. Trend test was used to check the change of UAI in different characteristic stratums during the study period. RESULTS: In total, 58.4% (range from 54.5% to 62.0%) of the participants reported that they engaged in UAI in the past six months. Participants who aged less than 20 [Adjusted Odds Ratio (AOR): 2.22, 95% Confidential Interval (CI): 1.07-4.61], only attended elementary school (or less) (AOR: 1.41, 95% CI: 1.04-1.90), cohabiting with male partner (AOR: 2.15, 95% CI: 1.66-2.79), divorced or widowed (AOR: 2.80, 95% CI: 1.54-5.07), did not test for HIV in the past year (AOR: 1.36, 95% CI: 1.12-1.65), and had 10 or more partners in the past six months (AOR: 1.85, 95% CI: 1.18-2.91) had higher odds of UAI. However, the proportions of UAI were stable in different stratums during the study period. CONCLUSIONS: The proportion of MSM engaged in UAI was consistently high during the study period. Effective intervention strategies, which include but not limit to risk reduction counseling and testing services, are urgently needed to bring down the risk behaviors of the MSM in Guangzhou, in order to control HIV/STIs epidemic in this specific population.
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Homosexualidad Masculina/estadística & datos numéricos , Sexo Inseguro/estadística & datos numéricos , Adolescente , Adulto , Anciano , China , Estudios Transversales , Encuestas Epidemiológicas , Homosexualidad Masculina/psicología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Sexo Inseguro/psicología , Adulto JovenRESUMEN
Although methadone maintenance treatment (MMT) is an important means of HIV control, MMT clinics commonly have high attrition rates. The randomized controlled trial investigated the relative efficacy of adding a psycho-social intervention to the standard-of-care MMT in reducing attrition and non-attendance among first-time newly admitted MMT users in China (n = 288). Social workers implemented this three-phase intervention that was based on a behavioral maintenance theory. It also involved participants' family members and rectified some MMT-related misconceptions. As compared to the control group, the intervention group showed significantly lower likelihood of attrition (HR = 0.55, 95% confidence interval 0.39-0.80), lower estimated probability of attrition at Month 12 (0.35 vs. 0.55), and higher median number of days of attendance (Month 6: 147 vs. 91 days, p < 0.001; end-date: 225 vs. 142 days, p < 0.001). Further psycho-social services and translational research are warranted.
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Dependencia de Heroína/tratamiento farmacológico , Cumplimiento de la Medicación , Metadona/uso terapéutico , Narcóticos/uso terapéutico , Tratamiento de Sustitución de Opiáceos/métodos , Educación del Paciente como Asunto/métodos , Adulto , China , Femenino , Infecciones por VIH/prevención & control , Dependencia de Heroína/psicología , Humanos , Masculino , Resultado del TratamientoRESUMEN
Background: Leptospirosis, which is an easily overlooked zoonotic disease, was once widespread in Guangzhou, China. However, due to the implementation of control measures, the number of cases is decreasing. Based on the characteristics of leptospirosis cases in Guangzhou, China, between 1955 and 2020, we describe the changes and achievements in prevention and control management strategies over that period. Methods: The development of the leptospirosis control system in Guangzhou occurred over three periods: Period I: 1955-1978; Period II: 1979-2000; and Period III: 2001-2020. Data about leptospirosis cases were obtained from the Guangzhou Center for Disease Control and Prevention (CDC) and national health departments. The demographic characteristics of leptospirosis patients were analyzed using descriptive statistics. Results: During Period I, only the Guangzhou CDC and medical institutions at every level participated in the leptospirosis control system. During Period II, additional types of organizations, including local CDCs, countryside committees, community committees, and the Patriotic Health Movement Commission, were involved in the control system. Additionally, strong links were established between different organizations. After entering Period III, an increasing number of departments joined the cooperation, and the management of human patients was expanded to include the management of host animals, and thus, the prevalence of leptospirosis was monitored and controlled in various ways. The leptospirosis control system in Guangzhou has been further improved. From 1955 to 2020, a total of 2501 leptospirosis cases were recorded in Guangzhou, and the number of cases decreased significantly over time, from 1608 (Period I) to 744 (Period II) and then to 149 (Period III). Conclusion: The improvements of the leptospirosis control system in Guangzhou that occurred over decades were associated with a marked decrease in the number of leptospirosis cases. Guangzhou's experience can provide guidance for other countries or cities around the world facing similar challenges.
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Since the global outbreak of coronavirus disease 2019 (COVID-19), it has spread rapidly around the world. The nucleocapsid (N) protein is one of the most abundant SARS-CoV-2 proteins. Therefore, a sensitive and effective detection method for SARS-CoV-2 N protein is the focus of research. Here, we developed a surface plasmon resonance (SPR) biosensor based on the dual signal-amplification strategy of Au@Ag@Au nanoparticles (NPs) and graphene oxide (GO). Additionally, a sandwich immunoassay was utilized to sensitively and efficiently detect SARS-CoV-2 N protein. On the one hand, Au@Ag@Au NPs have a high refractive index and the capability to electromagnetically couple with the plasma waves propagating on the surface of gold film, which are harnessed for amplifying the SPR response signal. On the other hand, GO, which has the large specific surface area and the abundant oxygen-containing functional groups, could provide unique light absorption bands that can enhance plasmonic coupling to further amplify the SPR response signal. The proposed biosensor could efficiently detect SARS-CoV-2 N protein for 15 min and the detection limit for SARS-CoV-2 N protein was 0.083 ng/mL, with a linear range of 0.1 ng/mL~1000 ng/mL. This novel method can meet the analytical requirements of artificial saliva simulated samples, and the developed biosensor had a good anti-interference capability.
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Técnicas Biosensibles , COVID-19 , Nanopartículas del Metal , Humanos , Resonancia por Plasmón de Superficie/métodos , Técnicas Biosensibles/métodos , SARS-CoV-2 , Oro , Inmunoensayo/métodos , COVID-19/diagnósticoRESUMEN
OBJECTIVE: To investigate the effectiveness of psychosocial services provided by social workers in reducing dropout rate and increasing treatment dosage in methadone maintenance treatment (MMT) users. METHODS: From May in 2009 to April in 2010, 300 MMT users were recruited from three MMT clinics in Guangzhou, and were randomly allocated into the intervention group and the control groups. The control group (152 cases) received standard MMT services while the intervention group (148 cases) received additional services provided by social workers. Methadone dosage, dropout rate, perceptions toward MMT etc. were compared between the two groups. RESULTS: The 1-month dropout rate of the control and intervention groups were 19.7% (30/152) and 6.8% (10/148) (P < 0.05) respectively; the 6-month dropout rate of the control and intervention groups were 75.5% (115/152) and 50.7% (75/148) (P < 0.05) respectively. The intervention group had higher average treatment dosage than the control group ((56.0 ± 21.2) vs (64.4 ± 23.1) ml/d, (58.0 ± 24.0) vs (66.1 ± 26.6) ml/d, P < 0.05). At 1-month and 6-month, the intervention group had higher scores of MMT-related perception ((1.26 ± 0.68) vs (1.84 ± 0.95), (1.55 ± 0.83) vs (2.44 ± 1.23), P < 0.05), self-efficacy of maintenance ((3.68 ± 1.33) vs (4.20 ± 1.05), (3.80 ± 1.38) vs (4.43 ± 0.79), P < 0.05) and satisfaction toward MMT((4.08 ± 0.54) vs (4.15 ± 0.60), (4.01 ± 0.67) vs (4.31 ± 0.64), P < 0.05) as compared to the control group. The reverse was true for the score of negative experiences ((1.05 ± 0.86) vs (0.96 ± 0.92), (1.46 ± 0.87) vs (1.11 ± 1.07), P < 0.05). CONCLUSION: The psychosocial interventions provided by social workers were effective in reducing dropout rate, increasing treatment dosage and improving cognitions of MMT users.
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Metadona/uso terapéutico , Tratamiento de Sustitución de Opiáceos , Servicio Social , Adulto , Femenino , Dependencia de Heroína/tratamiento farmacológico , Humanos , Masculino , Metadona/administración & dosificación , Cooperación del Paciente , Centros de Tratamiento de Abuso de Sustancias , Resultado del TratamientoRESUMEN
The SARS-CoV-2 B.1.617.2 (Delta) variant flared up in late May in Guangzhou, China. Transmission characteristics of Delta variant were analysed for 153 confirmed cases and two complete transmission chains with seven generations were fully presented. A rapid transmission occurred in five generations within 10 days. The basic reproduction number (R0) was 3.60 (95% confidence interval: 2.50-5.30). After redefining the concept of close contact, the proportion of confirmed cases discovered from close contacts increased from 43% to 100%. With the usage of a yellow health code, the potential exposed individuals were self-motivated to take a nucleic acid test and regained public access with a negative testing result. Facing the massive requirement of screening, novel facilities like makeshift inflatable laboratories were promptly set up as a vital supplement and 17 cases were found, with 1 pre-symptomatic. The dynamic adjustment of these three interventions resulted in the decline of Rt from 5.00 to 1.00 within 9 days. By breaking the transmission chain and eliminating the transmission source through extending the scope of the close-contact tracing, health-code usage and mass testing, the Guangzhou Delta epidemic was effectively contained.
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A respondent-driven sampling survey was conducted to investigate HIV related serological and behavioral characteristics of men who have sex with men (MSM) in Guangzhou, China, and to identify associated factors potentially driving the epidemic. Respondent-Driven Sampling Analysis Tool and SPSS were used to generate adjusted estimates and to explore associated factors. Three hundred seventy-nine eligible participants were recruited. The adjusted prevalence of HIV and current syphilis infection are 5.2% and 17.5% respectively. 60.3% have unprotected anal sex in the past 6 months. Unprotected anal sex, having receptive anal sex and current syphilis infection are significant factors associated with HIV infection. The potential for a rapid rise of HIV and syphilis infections among MSM in Guangzhou exists. Targeted interventions with voluntary counseling and testing (VCT) and sexually transmitted infection (STI) services are needed to address the epidemic, with a focus on such subgroups as those of with current syphilis, and non-official Guangzhou residence status.
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Infecciones por VIH/epidemiología , Homosexualidad Masculina/estadística & datos numéricos , Asunción de Riesgos , Sífilis/epidemiología , Adulto , China/epidemiología , Estudios de Seguimiento , Infecciones por VIH/transmisión , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Parejas Sexuales , Factores Socioeconómicos , Encuestas y Cuestionarios , Sífilis/transmisión , Sexo Inseguro/estadística & datos numéricos , Adulto JovenRESUMEN
BACKGROUND: We conducted molecular analyses to confirm four clustering HIV-1 infections (Patient A, B, C & D) in Guangzhou, China. These cases were identified by epidemiological investigation and suspected to acquire the infection through a common heterosexual transmission chain. METHODS: Env C2V3V4 region, gag p17/p24 junction and partial pol gene of HIV-1 genome from serum specimens of these infected cases were amplified by reverse transcription polymerase chain reaction (RT-PCR) and nucleotide sequenced. RESULTS: Phylogenetic analyses indicated that their viral nucleotide sequences were significantly clustered together (bootstrap value is 99%, 98% and 100% in env, gag and pol tree respectively). Evolutionary distance analysis indicated that their genetic diversities of env, gag and pol genes were significantly lower than non-clustered controls, as measured by unpaired t-test (env gene comparison: p < 0.005; gag gene comparison: p < 0.005; pol gene comparison: p < 0.005). CONCLUSION: Epidemiological results and molecular analyses consistently illustrated these four cases represented a transmission chain which dispersed in the locality through heterosexual contact involving commercial sex worker.
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Infecciones por VIH/epidemiología , Infecciones por VIH/transmisión , VIH-1/clasificación , VIH-1/genética , China/epidemiología , Análisis por Conglomerados , Femenino , Genotipo , Infecciones por VIH/virología , VIH-1/aislamiento & purificación , Heterosexualidad , Humanos , Masculino , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , ARN Viral/sangre , Análisis de Secuencia de ADN , Homología de Secuencia , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genéticaRESUMEN
INTRODUCTION: Previous studies have reported a possibly increasing HIV prevalence among men who have sex with men (MSM) in China. However there have been limited systematic analyses of existing surveillance data to learn the trend of HIV prevalence and factors driving the trend. The aims of this study were to examine the trend of HIV prevalence among MSM in Guangzhou and to explore the role of unprotected anal intercourse (UAI) in the trend. METHODS: Snow-ball sampling was applied in the subject recruitment for the annual serological and behavioral surveys among MSM from 2008 to 2013. Data collected in the behavioral survey include demographic information, HIV related sexual behavior with men and women, access to HIV prevention services, and symptoms of sexually transmitted infections. Chi-square test was used to analyze the trend of HIV prevalence. Multivariate logistic regression was conducted to test the factors associated with HIV infection. RESULTS: HIV prevalence increased significantly from 5.0% in 2008 to 11.4% in 2013 while syphilis prevalence decreased from 17.4% to 3.3% in the same period. UAI rates were high and stable in every single year, ranging from 54.5% to 62.0%. Those who were having UAI (ORâ=â1.80, 95% confidence interval (CI): 1.26-2.58), being migrants, having more than 10 partners, and infected with syphilis had higher risk for HIV infection. CONCLUSIONS: HIV epidemic is expanding in Guangzhou. The persistently high UAI may have played a major role in the increasing trend of HIV prevalence. Targeted prevention program should be conducted among MSM who are migrants, low educational level, syphilis infected, or having multiple partners to encourage HIV test and change UAI behavior. The general high UAI calls for tailored intervention program to promote healthy culture and form a safe sex social norm in the MSM community.
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Infecciones por VIH/epidemiología , Homosexualidad Masculina , Conducta Sexual , Sífilis/epidemiología , Adulto , China , Coito , Femenino , Infecciones por VIH/microbiología , Infecciones por VIH/patología , Seropositividad para VIH , Humanos , Masculino , Sífilis/microbiología , Sífilis/patología , Sexo InseguroRESUMEN
OBJECTIVE: To explore the feasibility of offering HIV counseling and testing in community health centers (CHCs) and to provide evidence for the HIV/AIDS response in China. METHODS: Forty-two CHCs were selected from the eight cities that participated in the study. Rapid testing was mainly provided to: clients seeking HIV testing and counseling (HTC); outpatients with high-risk behavior of contracting HIV; inpatients and outpatients of key departments. Aggregate administrative data were collected in CHCs and general hospitals and differences between the two categories were compared. RESULTS: There were 23,609 patients who underwent HIV testing, accounting for 0.37% of all estimated clinic visits at the 42 sites (0.03%-4.35% by site). Overall, positive screening prevalence was 0.41% (95% confidence interval [CI] 0.33%-0.49%, range 0.00%-0.98%), which is higher than in general hospitals (0.17%). The identification efficiency was 0.22% (95% CI: 0.16%-0.27%) in pilot CHCs, 3.5 times higher than in general hospitals (0.06%) (Chi square test = 95.196, p<0.001). The percentage of those receiving confirmatory tests among those who screened positive was slightly lower in CHCs (73.7%) than in general hospitals (80.1%) (Chi-square test = 17.472, p<0.001). Composition of clients mobilized for testing was consistent with the usage of basic public health and medical services in CHCs. The rate of patients testing HIV positive was higher among patients from key CHC departments (0.68%) than among high-risk Voluntary Counseling and Testing (VCT) clients (0.56%), those participating in outreach activities (0.41%), pregnant women (0.05%), and surgical patients (0.00%). CONCLUSION: This project demonstrates that providing HIV testing services for patients who exhibit high risk behavior has a high HIV case detection rate and that CHCs have the capacity to integrate HTC into routine work. It provides concrete evidence supporting the involvement of CHCs in the expansion of HIV/AIDS testing and case finding.
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Serodiagnóstico del SIDA/métodos , Serodiagnóstico del SIDA/estadística & datos numéricos , Ciudades/estadística & datos numéricos , Centros Comunitarios de Salud/estadística & datos numéricos , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Adulto , China/epidemiología , Consejo/estadística & datos numéricos , Femenino , Hospitales Generales/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto JovenRESUMEN
AIMS: To investigate the incidence of dropout and the prevalence of poor adherence among newly admitted first-time clients of methadone maintenance treatment (MMT) clinics, and the associations between MMT-related misconceptions and these two treatment outcomes. DESIGN: A cohort study (maximum follow-up period = 17.6 months) was conducted. SETTING: Three of the nine MMT clinics in Guangzhou, China participated in the study. PARTICIPANTS: The sample included 158 newly admitted first-time MMT clients. MEASUREMENTS: Information collected included background characteristics, history of drug use, MMT-related misconceptions, dropout during the entire study period and poor adherence within the first 6 months since admission to MMT. FINDINGS: Of all newly admitted MMT clients, 98.2% possessed at least one and 50.6% possessed all four types of MMT-related misconception; 51.3% had dropped out before the completion of the study [95% confidence interval (CI): 43.5-59.1%] and 62% exhibited poor adherence within the first 6 months since admission (95% CI: 54.2-69.6%). Adjusting for significant background variables, the number of misconceived responses predicted significantly both dropout [hazard ratio (HR) = 3.80 for two to three misconceived items, HR = 7.13 for four misconceived items, with zero to one misconceived item being the reference] and poor adherence within the first 6 months [relative risk (RR) = 4.13 for two to three misconceived items; RR = 4.40 for four misconceived items, with zero to one misconceived item being the reference. CONCLUSIONS: Among opiate addicts in China prescribed methadone maintenance therapy for the first time, misconceptions about this medication are prevalent and are associated with poor adherence to the medication regimen and a high a rate of dropout from the treatment programme.
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Cumplimiento de la Medicación/psicología , Metadona/uso terapéutico , Narcóticos/uso terapéutico , Tratamiento de Sustitución de Opiáceos/psicología , Trastornos Relacionados con Opioides/rehabilitación , Malentendido Terapéutico/psicología , Adulto , Anciano , Actitud Frente a la Salud , China/epidemiología , Femenino , Humanos , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Persona de Mediana Edad , Trastornos Relacionados con Opioides/epidemiología , Pacientes Desistentes del Tratamiento/psicología , Pacientes Desistentes del Tratamiento/estadística & datos numéricos , Estudios ProspectivosRESUMEN
The methadone maintenance treatment (MMT) program is scaling up in China, but little is known about drug users' cognitions of MMT. To investigate the prevalence and associated factors of MMT-related misconceptions, a totally of 300 newly admitted MMT users were interviewed in three MMT clinics in Guangzhou. Four statements were used to assess MMT-related misconceptions. The results showed that the majority of participants misconceived that MMT is intended primarily for detoxification (92.3%), that one could be completely detoxified and quit using methadone after using it for 2-3months (64.2%), that MMT is not a long-term or even lifetime treatment (77.9%); and that one should attempt to reduce its treatment dosage as methadone is harmful to one's health (84.3%); 48.5% of the respondents possessed all four types of misconceptions. Prior experience of methadone use in voluntary drug detoxification centers (OR=1.82 to 2.55, p<0.05) was associated with some misconception items, whilst being introduced by some peer drug users or community members to use MMT (versus not being introduced by anyone; OR=0.38 to 0.50, p<0.05), having taken up HIV voluntary counseling and testing prior to admission (OR=0.52, p<0.05), and a higher HIV-related knowledge level (OR=0.38, p<0.05) were associated with lower likelihoods for possessing some of the misconceptions. The findings suggested that MMT-related misconceptions were very prevalent among newly recruited MMT users in China. Misconceptions are potential factors causing drop-outs. Interventions targeting such misconceptions are greatly warranted.