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BACKGROUND: The antioxidant properties of tea extracts are considered to be effective in protecting against cataracts. However, there is still insufficient epidemiological knowledge about the protective effects of different types of tea on age-related cataracts. METHODS: The data was derived from the Zhejiang Major Public Health Surveillance (ZJMPHS) Program on health and related factors in the elderly. The relationships between consumption of different types of tea and risk of age-related cataracts were assessed after adjusting for related covariates. RESULTS: The prevalence of age-related cataracts in this study population was 4.4% (409/9343). After adjustment for potential confounders, tea drinking was associated with reduced risk of age-related cataracts (adjusted odds ratio [OR] 0.65; 95% confidence interval [CI], 0.47-0.91). Compared to nondrinkers, green tea drinkers had a significantly reduced risk of cataracts (adjusted OR 0.58; 95% CI, 0.40-0.85). Average tea consumption of 14-27 cups (adjusted OR 0.55; 95% CI, 0.33-0.93) and over 28 cups (adjusted OR 0.58; 95% CI, 0.34-0.99) per week had a protective effect against cataracts in comparison to no consumption. In addition, ingesting a moderate concentration of tea significantly decreased the risk of cataract compared to no consumption (adjusted OR 0.43; 95% CI, 0.27-0.71). CONCLUSIONS: Tea ingestion was associated with reduced risk of age-related cataracts. In light of these findings, we suggest that reasonable tea consumption (ie, favoring green tea and consuming an average of over 500 mL per day at moderate concentration) should offer protection against age-related cataracts.
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Envejecimiento , Catarata/epidemiología , Té , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Vigilancia en Salud Pública , RiesgoRESUMEN
BACKGROUND: The third wave of H7N9 cases in China emerged in the second half of 2014. This study was conducted to identify the risk trends of H7N9 virus in human infections and environment contamination. METHODS: A surveillance program for H7N9 virus has been conducted in all 90 counties in Zhejiang since March 2013. All H7N9 cases were reported by hospitals through the China Information System for Disease Control and Prevention. Sampling sites for environment specimens were randomly selected by a multi-stage sampling strategy. Poultry-related workers for serological surveillance were randomly selected from the sampling sites for environmental specimens in the first quarter of each year. rRT-PCR and viral isolation were performed to identify H7N9 virus. A hemagglutination inhibition assay was conducted to detect possible H7N9 infection among poultry-related workers. RESULTS: A total of 170 H7N9 cases were identified in Zhejiang from 20 March 2013 to 28 February 2015. The proportion of rural cases increased from 42.2% (19/45) to 67.7% (21/31) with progression of the three epidemics (P < 0.05). In 32% (161/503) of towns and 16.0% (238/1488) of surveyed premises, H7N9 virus was detected in the environment. The positive rate of environmental specimens was 6.1% (868/14207). In addition, 912 poultry-related workers were recruited and 3.7% (34) of them tested positive for H7N9 antibodies. Positive detection of H7N9 virus during environmental surveillance increased from the first to third wave (P < 0.05). Almost all positive rates of environmental surveillance were higher in urban than rural in the second wave (P < 0.05), however they were higher in rural area in the third wave (P < 0.05). CONCLUSIONS: Our study highlights that the severity of poultry-related environmental contamination by H7N9 virus is intensifying. We strongly recommend that the local government stop illegal trading immediately and close live poultry markets in the territory. Poultry operations in slaughtering plants must be supervised rigorously. Prior to the closure of live poultry markets, daily cleaning and disinfecting of areas potentially contaminated by H7N9 virus, centralized collection and disposal of trash, designating certain days as market rest days, banning overnight poultry storage and other measures should be strictly carried out in both urban and rural areas.
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Contaminación Ambiental/efectos adversos , Subtipo H7N9 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/transmisión , Gripe Humana/virología , Población Rural/estadística & datos numéricos , Animales , Anticuerpos Antivirales/sangre , China/epidemiología , Trazado de Contacto , Desinfección/métodos , Monitoreo del Ambiente , Contaminación Ambiental/prevención & control , Humanos , Gripe Aviar/epidemiología , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Gripe Humana/transmisión , Masculino , Persona de Mediana Edad , Aves de Corral , RiesgoRESUMEN
OBJECTIVE: To construct a forecasting model of influenza-like illness in Zhejiang Province. METHODS: The number of influenza-like cases and related pathogens among outpatients and emergency patients were obtained from 11 sentinel hospitals in Zhejiang Province during 2012 to 2013 (total 104 weeks), and corresponding meteorological factors were also collected. The epidemiological characteristics of influenza during the period were then analyzed. Linear correlation and rank correlation analyses were conducted to explore the association between influenza-like illness and related factors. Optimal parameters were selected by cross validation. Support vector machine was used to construct the forecasting model of influenza-like illness in Zhejiang Province and verified by the historical data. RESULTS: Correlation analysis indicated that 8 factors were associated with influenza-like illness occurred in one week. The results of cross validation showed that the optimal parameters were C=3, ε=0.009 and γ=0.4. The results of influenza-like illness forecasting model after verification revealed that support vector machine had the accuracy of 50.0% for prediction with the same level, while it reached 96.7% for prediction within the range of one level higher or lower. CONCLUSION: Support vector machine is suitable for early warning of influenza-like illness.
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Gripe Humana/epidemiología , Vigilancia de Guardia , Máquina de Vectores de Soporte , China/epidemiología , Predicción , HumanosRESUMEN
OBJECTIVE: To assess the risk of local transmission of Dengue caused by introduced cases with semi-quantitative method in 2015 in Zhejiang Province. METHODS: Risk indexes of local transmission of Dengue caused by introduced cases were reviewed. The weights of indexes were computed by analytic hierarchy process and further used to generate absolute risk values by multiplying indexes. Moreover, comprehensive indexes were computed to describe relative risk by combining analytic hierarchy process and TOPSIS methods. RESULTS: Four primary indexes and 19 secondary indexes were identified for risk assessment of local transmission of Dengue. The indexes with maximum and minimum weight were the number of immigration from countries with Dengue patients (weight value: 0.0678) and density of population (weight value: 0.0371) respectively. All CR values, statistics for measuring consistency of score matrix, were less than 0.1 (minimum: 0.000, maximum: 0.0922, average: 0.0251). The absolute risk of Zhejiang Province was within the range of 0.397-0.504 (the full score was 1.0). The risk orders of 11 municipalities sorted by relative comprehensive indexes and absolute risk values methods were similar. The three highest municipalities were Hangzhou, Wenzhou and Ningbo and the ranges of absolute risk value were 0.387-0.494, 0.404-0.511 and 0.392-0.499 respectively. CONCLUSION: The results provides scientific basis for preventing and controlling Dengue in Zhejiang Province. The indexes and weights may be used to assess risk of Dengue in future. In addition, the semi-quantitative method constructed in this study would be a significant reference for risk assessment of public health in emergencies.
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Dengue/epidemiología , Dengue/transmisión , Medición de Riesgo , China/epidemiología , HumanosRESUMEN
OBJECTIVE: To determine a dengue fever outbreak in Yiwu city, Zhejiang Province in 2009 and to trace the origin of the pathogen. METHODS: The dengue virus IgM, IgG antibodies and viral nucleic acid were detected and virus was isolated using 40 serum samples from the suspected patients. The viral RNA of the isolated virus strains was extracted and the E gene was amplified by RT-PCR. The amplicons were sequenced and the phylogenetic and homological analyses were also constructed. RESULTS: Among 40 serum samples from dengue fever suspected patients, 17 were positive from for dengue IgM (42.5%); 4 were IgG positive (10.0%); 34 samples were dengue virus RNA positive (85.0%), 28 dengue virus type 3 (D3) strains were isolated (70.0%). The complete coding region of envelope genes (E) from 13 D3 strains was all 1479 nt without any insertion or deletion, which encoded with 493 amino acids (aa). E gene from the 13 D3 strains from Zhejiang in 2009 (D3/ZJ/2009) was 100.0% identical. The strain from Saudi Arabia shared the highest similarity with the D3 strain, 99.3% and 100.0% of their E genes and deduced amino acids were identical, respectively, whereas they were 93.4% and 97.4% between D3/ZJ/2009 strain and its prototype strain (D3/H87/1956), and 93.6% and 97.4% between D3/ZJ/2009 and a D3 strain isolated in Guangxi Province in 1980. The phylogenetic tree of E genes also indicated that D3/ZJ/2009 had maximum similarity with the D3/Saudi Arabia/2004. They all belonged to the D3/GIII branch, which was originated from Indian Subcontinent. CONCLUSION: The outbreak of dengue fever in Zhejiang in 2009 was caused by type 3 dengue virus III genotype. The virus was most likely originated from Saudi Arabia.
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Virus del Dengue/aislamiento & purificación , Dengue/epidemiología , Dengue/virología , Brotes de Enfermedades , Adolescente , Adulto , Anciano de 80 o más Años , China/epidemiología , Virus del Dengue/clasificación , Virus del Dengue/genética , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Breastfeeding is related to maternal health. However, the association of women's breastfeeding duration with cognitive function in their later life is limited and inconsistent. The aim of this study was to accurately evaluate the association in Chinese postmenopausal women. We analyzed the data from Zhejiang Ageing and Health Cohort Study including 5487 postmenopausal women. Cognitive impairment was assessed via the Mini-Mental State Examination. Data on breastfeeding duration was collected in the reproductive history section within the questionnaire. Generalized additive models (GAMs) and logistic regression models, controlled for an extensive range of potential confounders, were generated to examine the associations. A U-shaped association was identified between breastfeeding duration and cognitive impairment based on GAM. The nadir with lowest odds of cognitive impairment was ascertained by quadratic model as 12 months. The logistic models showed that compared with women breastfeeding 12 months per child, the fully adjusted odds ratios (ORs) were 1.50 (95% Confidence Interval (CI): 1.20-1.88), 1.58 (95% CI: 1.29-1.93), 1.33 (95% CI: 1.06-1.68), 2.08 (95% CI: 1.64-2.65) for those averagely breastfeeding <6, 6-<12,>12-18,>18 months, respectively. Furthermore, we did not observe significant effect modification of the association. Future longitudinal studies are needed to confirm the association.
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Lactancia Materna , Disfunción Cognitiva/fisiopatología , Posmenopausia/fisiología , Adulto , Anciano , China/epidemiología , Cognición/fisiología , Disfunción Cognitiva/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Factores de Riesgo , Factores Socioeconómicos , Factores de TiempoRESUMEN
OBJECTIVE: To analyse the independent and combined associations of postlunch napping duration and night-time sleep duration with risk of cognitive impairment among Chinese elderly. DESIGN: A cross-sectional study. SETTING: We analysed the data from Zhejiang Ageing and Health Cohort, a population-based survey of seven counties located in Zhejiang province in eastern China. PARTICIPANTS: 10 740 participants aged 60 years or older were included in final analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: Cognitive impairment was assessed through Mini-Mental State Examination. Data on sleep-related characteristics was collected in the behavioural habits section within the questionnaire. RESULTS: Relative to participants with 1-30 min of postlunch napping, those who did not nap and who napped longer had significantly higher risks for cognitive impairment. OR of cognitive impairment were 1.41 (95% CI 1.14 to 1.75) for participants with longer night-time sleep duration (≥9 hours), compared with those sleeping 7-8.9 hours. In addition, combined effects were further identified. Participants with both longer night-time sleep duration (≥9 hours) and longer postlunch napping duration (>60 min) (OR=2.01, 95% CI 1.30 to 3.13), as well as those with both longer night-time sleep duration (≥9 hours) and appropriate postlunch napping duration (1-30 min) (OR=2.01, 95% CI 1.20 to 3.38), showed significantly higher risk of cognitive impairment than those with sleeping 7-8 hours and napping 1-30 min. Meanwhile, a 34% increase in odds of cognitive impairment was observed in participants with both shorter night-time sleep duration (5-6.9 hours) and no napping. CONCLUSION: Both postlunch napping duration and night-time sleep duration were independently and jointly associated with cognitive impairment, which needs verification in prospective studies.
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Ritmo Circadiano , Disfunción Cognitiva/etiología , Almuerzo , Sueño , Anciano , Anciano de 80 o más Años , China , Estudios de Cohortes , Femenino , Humanos , Masculino , Pruebas de Estado Mental y Demencia , Persona de Mediana Edad , Vigilancia de la Población , Factores de Riesgo , Factores de TiempoRESUMEN
BACKGROUND: Epidemiological studies suggest that higher tea consumption was associated with lower risk of depressive symptoms, but this has not been found consistently. Moreover, the effect of different types of tea on depressive symptoms needs to be further explored. This study aimed to examine the association between tea consumption and depressive symptoms in Chinese elderly. METHODS: We analyzed the baseline data from Zhejiang Major Public Health Surveillance Program including 9371 participants. Depressive symptoms was assessed through the application of Patient Health Questionnaire-9 scale (PHQ-9). Logistic regression models, controlled for an extensive range of potential confounders, were generated to evaluate the association between tea consumption and risk of depressive symptoms. RESULTS: The black tea drinkers had a significantly decreased risk of depressive symptoms (p<0.01), whereas no association was found in green tea drinkers. Compared with non-drinkers, the adjusted ORs (95% CIs) were 0.48 (0.23, 0.99) and 0.35 (0.17, 0.72) for participants consuming <3 cups and ≥3 cups of black tea per day, respectively (P for trend: <0.01). A linear association between concentration of black tea and depressive symptoms was also confirmed in our study. LIMITATIONS: Cross-sectional data could not make a causation conclusion, and the observed association in our study could not be ascribed to any specific component in tea. CONCLUSIONS: Our results indicated that higher black tea consumption was associated with a lower prevalence of depressive symptoms in the elderly.
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Bebidas/estadística & datos numéricos , Depresión/epidemiología , Depresión/prevención & control , Té , Anciano , Pueblo Asiatico/estadística & datos numéricos , China/epidemiología , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Prevalencia , Factores de RiesgoRESUMEN
BACKGROUND: Epidemiological studies suggest that proxies of higher lifetime estrogen exposure are associated with better cognitive function in postmenopausal women, but this has not been found consistently. OBJECTIVE: To determine whether reproductive history, an important modifier of estrogen exposure across the lifetime, is associated with risk of cognitive impairment in postmenopausal women. METHODS: We analyzed the baseline data from Zhejiang Major Public Health Surveillance Program (ZPHS) including 4,796 postmenopausal women. Cognitive impairment was assessed through the application of Mini-Mental State Examination questionnaire. Logistic regression models, controlled for an extensive range of potential confounders, were generated to examine the associations between women's reproductive history and risk of cognitive impairment in their later life. RESULTS: The length of reproductive period was inversely associated with risk of cognitive impairment (pâ=â0.001). Odds ratio (OR) of cognitive impairment were 1.316 (95% CI 1.095â¼1.582) for women with 5 or more times of full-term pregnancies, compared with those with 1â¼4 times of full-term pregnancies. Women without incomplete pregnancy had a significant higher risk of cognitive impairment (ORâ=â1.194, 95% CI 1.000â¼1.429), compared with the reference (1â¼2 times of incomplete pregnancies). Oral contraceptive use (ORâ=â0.489, 95% CI 0.263â¼0.910) and intrauterine device (IUD) use (ORâ=â0.684, 95% CI 0.575â¼0.815) were associated with significantly reduced risk of cognitive impairment. CONCLUSION: Our results indicated that shorter reproductive period, higher number of full-term pregnancies and no incomplete pregnancy history were associated with an increased risk of cognitive impairment. In contrast, oral contraceptive and IUD use corresponded to reduced risk of cognitive impairment.
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Trastornos del Conocimiento/diagnóstico , Estrógenos/sangre , Posmenopausia/psicología , Historia Reproductiva , Anciano , Anciano de 80 o más Años , China , Cognición , Anticonceptivos Orales , Estudios Transversales , Femenino , Humanos , Dispositivos Intrauterinos , Modelos Logísticos , Persona de Mediana Edad , Pruebas Neuropsicológicas , Oportunidad Relativa , Escalas de Valoración PsiquiátricaRESUMEN
OBJECTIVE: To understand the clinical and epidemiological characteristics of hand-foot-and-mouth disease (HFMD) deceased cases. METHOD: Information of demographics, diagnosis and treatment, clinical symptoms and signs, laboratory test results, and epidemiological contact history of 72 HFMD cases who died between May 2008 and September 2011, in Zhejiang Province, were collected and analyzed. RESULT: The average age of the 72 cases was 1.8 years, 45 were males, accounting for 62.5%, 63 (87.5%) of the cases were scattered children. Eighteen counties reported 2 or more deaths, accounting for 46.1% (18/39) among the counties where the deaths were reported. The deaths occurred mainly in April to August, the peak occurred in May and June. Fever (98.4%, 63/64) and rash (95.1%, 58/61) were the most common symptoms, but the rash was not obvious at the first diagnosis. Fever occurred before the rash (79.0%, 49/62), persisted for 4 days in average. Vomiting (71.9%, 46/64), dyspnea (65.6%, 42/64), cyanosis (53.1%, 34/64) and impaired consciousness (51.6%, 33/64) were often seen among the cases; 53.1% (34/64) cases went to see the doctor on the first day, but 82.5%(52/63)cases were misdiagnosed. Time to diagnosis of HFMD was in average 3 days. About 3 to 4 days after the onset, the disease deteriorated sharply, deaths occurred within 1 day after admission in 78.9%(45/57)of the deceased cases; 85.0% (34/40) cases had high white blood cells level, mainly neutrophils increased, the ratio of neutrophil was more than 70% in 55.6% (15/27) of cases. Enterovirus 71 (EV71) infection was found in 93.3% (56/60) cases, the deceased cases often died of pulmonary hemorrhage (42.9%, 21/49) and encephalitis (34.7%, 17/49). The sanitary conditions of the cases' family were poor (65.5%, 36/55), but 73.3% (33/45) cases had no exposure history. CONCLUSION: The HFMD deceased cases were mostly younger aged boys, scattered children, nonlocal-residents, and had poor sanitation. They were often infected with EV71, had high fever but had no typical rash, no clear exposure history, they had increased leukocyte, and were often misdiagnosed. Three or 4 days after onset, the disease deteriorated abruptly, most cases died within 1 week after onset. To decrease the HFMD mortality, early detection of severe cases should be stressed, and relative measures should be taken. The guardian should be aware of having good sanitary situation and healthy habits.
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Enterovirus Humano A/aislamiento & purificación , Enfermedad de Boca, Mano y Pie/epidemiología , Animales , Preescolar , China/epidemiología , Brotes de Enfermedades , Heces/virología , Femenino , Fiebre/etiología , Fiebre/patología , Enfermedad de Boca, Mano y Pie/mortalidad , Enfermedad de Boca, Mano y Pie/patología , Humanos , Lactante , Masculino , Estudios Retrospectivos , Distribución por SexoRESUMEN
BACKGROUND: The first outbreak of H5N1 highly-pathogenic avian influenza (HPAI) virus associated with several human deaths occurred in 1997 in Hong-Kong, China. While H5N1 virus infection in poultry workers has been studied in some detail, little is known about the environmental risk factors of the H5 avian influenza virus infection in China. METHODS: A cross-sectional study was performed to evaluate the environmental load of H5 viruses in poultry-contaminated environments and to explore potential risk factors associated with infection in poultry workers between October 2010 and March 2012. Serum and environmental samples were collected in Zhejiang province, China. The hemagglutination inhibition (HI) assay was used to analyze human sera for antibodies against H5N1 virus [A/Hubei/1/2010 (H5N1) and A/Anhui/1/2005 (H5N1)]. All participants were interviewed with a standardized questionnaire to collect information on exposure to poultry. H5 Avian influenza virus in the environmental samples was detected by real time RT-PCR. RESULTS: One hundred and five of 3,453 environmental samples (3.0%) tested positive for H5 avian influenza virus. Fifty-five of 1,169 subjects (4.7%) tested seropositive for anti-H5N1 antibodies. A statistically significant difference in H5 virus detection rate was found among the different environments sampled (<0.001), with the highest showed in live bird markets (68.6%). Detection rate varied according to the source of samples, sewage (9.5%), drinking water (19.0%), feces (19.0%), cage surface (25.7%), and slaughtering chopping boards (15.2%), respectively. Direct or close contact with poultry (OR =5.20, 95% CI, 1.53-17.74) and breeding numerous poultry (OR =3.77, 95% CI, 1.72-8.73) were significantly associated with seroprevalence of antibodies to avian influenza virus A (H5N1). CONCLUSIONS: The number of birds bred more than 1,000 and direct or close contact with poultry in the workplace or the environment would be a potential risk of H5N1 infection.
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OBJECTIVE: To analyze and evaluate the application of China Infectious Diseases Automated-alert and Response System(CIDARS)in Zhejiang province. METHODS: Data through the monitoring program in 2012 was analyzed descriptively and compared with the incidence data in the same period as well information related to public health emergency events. RESULTS: A total of 14 292 signals were generated on 28 kinds of infectious diseases in the system, in Zhejiang province. 100% of the signals had been responded and the median time to response was 0.81 hours. 123 signals (0.86%)were preliminarily verified as suspected outbreaks and 33 outbreaks were finally confirmed by further field investigation, with a positive ratio of 0.23% . Information related to regional distribution showed significant differences which reflecting a positive correlation between the numbers of diseases and the time of early-warning(r = 0. 97, P < 0.01). Distribution of information related to different types of diseases was also significantly different, showing a positive correlation between the prevalent strength of the disease and the amount of information in a specific area(r = 0.80, P < 0.01). CONCLUSION: CIDARS had a good performance which could be used to assist the local public health institutions on early detection of possible outbreaks at the early stage. However, the effectiveness was different for different regions and diseases.
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Control de Enfermedades Transmisibles/métodos , Brotes de Enfermedades/prevención & control , Vigilancia de la Población/métodos , China/epidemiología , Enfermedades Transmisibles/epidemiología , Humanos , Incidencia , Salud PúblicaRESUMEN
OBJECTIVE: To study a local hospital reported acute gastroenteritis in a boarding school on its source of infection, mode of transmission and risk factors of the infection. METHODS: A suspected case was defined as who had developed diarrhea (≥ 3 times/day) or vomiting among teachers or students of the school, during April 19 - 30, 2010. A confirmed case was from a probable case plus tested positive for norovirus in stool specimens by using RT-PCR. Stool specimens of cases and environmental specimens were collected for laboratory diagnosis. In a case-control study, we compared exposures to sources of bottled water, consumption of bottled water, and hygienic habits of 220 probable or confirmed cases from April 21 - 23 in the peak of the outbreak, together with another 220 controls, with frequency-matched by school grade. RESULTS: 20.3% of the 1536 students but none of the teachers developed the disease. 98.6% of the cases (n = 217) and 85.5% (n = 188) of the controls had drunk bottled water in the classroom (OR(M-H) = 12.3, 95%CI: 3.7 - 40.9). 47.9% (n = 104) of the cases and 41.5% (n = 78) of the controls had drunk unboiled bottled water in classroom (OR(M-H) = 3.8, 95%CI: 1.5 - 9.6). 47.9% (n = 104) of the cases and 48.4% (n = 91) of the controls had drunk bottled mixed water (boiled and unboiled) in the classroom (OR(M-H) = 2.8, 95%CI: 1.1 - 7.0). Stool specimens from 3 cases and one bottle of uncovered bottled water in classroom showed positive of having norovirus genotype II. Coliforms was cultured much higher rates than standard deviations in the bottled water. The factory making the bottled water was not licensed or having strict disinfection facilities. CONCLUSION: Bottled spring water contaminated by norovirus was responsible for this outbreak.
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Infecciones por Caliciviridae/epidemiología , Brotes de Enfermedades , Agua Potable/virología , Gastroenteritis/epidemiología , Adolescente , Niño , China/epidemiología , Femenino , Gastroenteritis/virología , Humanos , Masculino , Norovirus , Prevalencia , Instituciones Académicas , Microbiología del AguaRESUMEN
OBJECTIVE: To evaluate the epidemiological and serological efficacy after 10 years of vaccination against hemorrhagic fever with renal syndrome (HFRS) vaccines in Zhejiang province. METHODS: One county was randomly chosen as the research unit with all the healthy people between 16 and 60 years old were equally divided into study and control groups. The study group was vaccinated. Immunofluorescent antibody assay was used to test specific IgG antibody and Mcro-CPE method was used to test the titer of neutralizing antibody. RESULTS: Two weeks after the full-course immunization, the seroconversion rate became 100% (67/67, with 95% CI as 96.3%-100%) by immunofluorescent antibody test (IgG) and 44.4% (8/18 with 95% CI as 22.0%-69.0%) by neutralization test with GMT titers as 72.1 and 4.6 respectively. Booster immunization was provided one year later. Time span as two weeks prior to, one year, one and half years, two years, three years and five years after booster immunization, the rates of seroconversion on immunofluorescent antibody using IFAT method, were 28.6%, 83.3%, 75.0%, 53.1%, 22.6%, 10.0% and 55.0% respectively, and rates of seroconversion of neutralizing antibody by Mcro-CPE method were 14.8%, 55.6%, 35.0%, 31.3%, 26.0%, 10.0% and 50.0% respectively. Nine years after the reinforcement, the rates of seroconversion of immunofluorescent antibody by IFAT method was only 7.1%. The vaccinated group had no patient seen but the control group appeared 34 patients including 3 deaths. According to the ten-year observation, the vaccine seemed effective with the protection rate in population reached 100%. CONCLUSION: HFRS vaccine was effective on epidemiological, social and economical efficacy.
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Fiebre Hemorrágica con Síndrome Renal/epidemiología , Fiebre Hemorrágica con Síndrome Renal/prevención & control , Vacunación/métodos , Adolescente , Adulto , Animales , Femenino , Fiebre Hemorrágica con Síndrome Renal/inmunología , Humanos , Inmunización Secundaria/métodos , Masculino , Persona de Mediana Edad , Ratas , Vacunas Virales/administración & dosificación , Vacunas Virales/uso terapéutico , Adulto JovenRESUMEN
OBJECTIVE: To determine the risk factors involved in the typhoon episodes and to put forward and evaluate the intervention measures. METHODS: We defined a confirmed injury case as: 'a person with fall,scalpel and stab, collision, drowning, injuries and trauma due to flying debris and building collapse, asphyxiation due to entrapment in collapsed buildings by typhoon from 0 am,August 12 to 6 pm, August 14 2004' and a death case as: 'a person with fall, scalpel and stab, collision, drowning, injuries and trauma due to flying debris and building collapse, asphyxiation due to entrapment in collapsed buildings by typhoon from 0 am, August 12 to 12 am, August 18 2004'. We investigated all hospitalized injured cases in ten hospitals and telephoned to those who were not hospitalized and the cases of death. We did case-control study with 1 pair versus 2 cases. 74 cases were selected in ten hospitals. The controls were neighbors of the controls matched by occupation, sex, village, and within 5 years of age without injury in this typhoon. We asked the cases and the controls on their alertness regarding typhoon and what actions taken when typhoon arrived. RESULTS: There were 392 injury cases in all ten hospitals and 50 death cases. The attack rate of injury was 27.3 per 100 000. The fatal rate was 11.3% with the death rate 3.1 per 100 000. We investigated 209 injury cases and 31 death cases. The number of cases who were injured from 1 to 6 hours before typhoon landing accounted for 64.6% (155) of all cases. The peak of epidemic curve was 4 hours before the landing of typhoon. Data on the analysis of 74 cases and 148 controls revealed that 42% (31) of the cases were outside their homes before and during typhoon compared to 15% (22) of the controls (OR = 3.9, 95% CI: 1.9-7.7). Compared with 20% (30) control persons (OR = 17,95% CI: 4.2-68). 28% (21) cases did not receive the alert of typhoon before it arrived compared with 18% (27) control persons (OR = 3.3, 95% CI:1.3-8.6). 53% (39) of the cases did not pay attention to the alert of typhoon before typhoon arrived. CONCLUSION: Staying outdoor, not receiving or did not take seriously about the alert of typhoon seemed to be the risk factors of injury by the typhoon episode, suggesting that the government should increase the emergency preparedness and to raise the awareness on risks associated with typhoon.