目的 了解新型冠状病毒肺炎(简称新冠肺炎)疫情和疫苗大规模应急接种对儿童家长免疫接种观念和体验的影响.方法 2021年5月6日至2021年6月20日,在广州市预防接种服务手机软件(APP)上采用问卷调查方式,对4 171名儿童家长进行在线调查.结果 1911名(45.8％)对疫情期间暂停常规免疫措施表示赞同,1 508名(36.2％)表示新冠肺炎疫情期间,即使预防接种门诊未停诊也会主动推迟儿童免疫接种;对恢复接种后,接种单位的防护措施、现场秩序和服务质量表示满意的分别为2 959名(70.9％)、2 558名(61.3％)和2 399名(57.5％);3 437名(82.4％)表示新冠肺炎疫情增强其对预防接种的重视程度,1 415名(33.9％)儿童家长表示预防接种门诊停诊减弱其对预防接种及时性的重视,1 380名(33.1％)儿童家长对"暂缓接种不会影响免疫效果"的观点表示认可.相对于学历较高(大学及以上)、幼龄和年轻儿童家长,中等学历(指大学以下)、大龄和年龄稍长儿童家长,对接种单位在疫情期间采取的暂停预防接种门诊,及恢复接种期间采取的各项防护措施满意度相对较高,认为现场秩序和接种服务质量较前提高,其对新冠肺炎疫情的敏感性更高,倾向主动推迟接种,对预防接种重要性和及时性更重视,易受新冠肺炎疫情和停诊的影响.新冠肺炎疫情和恢复接种后接种单位的控制措施,造成1 882名(45.1％)儿童存在常规疫苗脱漏,前3位原因为门诊只有预约号但预约不到、门诊减少日接种量及门诊停诊.结论 广州市儿童家长对预防接种门诊在新冠肺炎疫情期间和恢复接种后的各项防控措施满意度为中等偏上,新冠肺炎疫情和预防接种门诊停诊对广州市儿童家长的免疫观念和行为产生双向影响,部分家长增加其对免疫接种的重视程度,少部分家长减弱其对预防接种及时性的重视程度,提示接种单位需合理安排工作人员和接种时间,缓解因新冠肺炎疫情积压造成的接种压力,有针对性的进行正面宣传引导,普及预防接种正确认知,消除儿童家长疑虑.

目的 研究广州市市政供水厂出厂水中pH值、耗氧量和三氯甲烷的含量情况和变化趋势,初步探索pH值、耗氧量和三氯甲烷的相关关系.方法 2003-2018年对广州市市政供水厂的出厂水进行抽样和检测,整理并分析480份监测样品数据.结果 所有监测样品中pH值、耗氧量和三氯甲烷含量都符合《生活饮用水卫生标准》GB 5749-2006标准.出厂水中pH值和三氯甲烷均呈现上升趋势,耗氧量呈现下降趋势.pH值和三氯甲烷在不同季度之间差异有统计学意义(H=16.934,P＜0.01;H=18.075,P＜0.01),不同季度耗氧量差异无统计学意义(H=3.474,P＞0.05).pH值、耗氧量和三氯甲烷含量在丰水期和枯水期差异均无统计学意义(UpH=28.405,P＞0.05;U耗氧量=27.705,P＞0.05;U三氯甲烷=8.201,P＞0.05).pH值与耗氧量呈负相关(r=-0.519,P＜0.01),与三氯甲烷含量呈正相关(r=0.366,P＜0.01);耗氧量与三氯甲烷含量呈负相关(r=-0.432,P＜0.01).结论 建议广州市市政供水厂综合考虑pH值、耗氧量和三氯甲烷含量之间的相关性,密切关注出厂水质量,以保障饮用水安全.

Background: There has been a significant decline in the morbidity of almost all infectious diseases during the COVID-19 pandemic. However, while the incidence of norovirus-related acute gastroenteritis declined in Guangzhou, China during the initial period of the pandemic, incidence increased significantly once the new school year began in September 2020.Methods: Norovirus-related acute gastroenteritis clusters and outbreaks were assessed in Guangzhou from 2015 to 2020. Medians and interquartile ranges were compared between groups using the Mann–Whitney U-test, and attack rates were calculated.Results: While 78,579 cases of infectious diarrhea were reported from 2015 to 2019, with an average of 15,716 cases per year, only 12,065 cases of infectious diarrhea were reported in 2020. The numbers of sporadic cases and outbreaks reported from January to August 2020 were lower than the average numbers reported during the same time period each year from 2015 to 2019 but began to increase in September 2020. The number of cases in each reported cluster ranged from 10 to 70 in 2020, with a total of 1,280 cases and an average attack rate of 5.85%. The median number of reported cases, the cumulative number of cases, and the attack rate were higher than the average number reported each year from 2015 to 2019. The intervention time in 2020 was also higher than the average intervention time reported during 2015–2019. The main norovirus genotypes circulating in Guangzhou during 2015–2020 included genogroup 2 type 2 (GII.2) (n = 79, 26.69%), GII.17 (n = 36, 12.16%), GII.3 (n = 27, 9.12%), GII.6 (n = 8, 2.7%), GII.4 Sydney_2012 (n = 7, 2.36%), and GII.4 (n = 6, 2.03%).Conclusions: Our findings illustrate the importance of maintaining epidemiological surveillance for viral gastroenteritis during the COVID-19 pandemic. Local disease prevention and control institutions need to devote sufficient human resources to control norovirus clusters.

目的 了解广州市网络外卖食品的卫生状况.方法 根据广州市人口分布情况、地域分布等因素,采用随机抽样方法对广州市11个区网络外卖食品进行监测,共计采集2 361份食品样品.所有样品均检测沙门菌、金黄色葡萄球菌、单增李斯特菌、副溶血性弧菌、蜡样芽胞杆菌5种致病菌,依据《广州市食品安全风险监测工作手册》的方法进行.使用R软件进行数据的统计分析.结果 2017-2019年连续3年的监测,在2 361份网络外卖食品中有306份检出致病菌,总检出率12.96％.其中蜡样芽胞杆菌的检出率最高(11.27％),其次为金黄色葡萄球菌(1.31％)、单增李斯特菌(0.47％)、沙门菌(0.17％),这4种致病菌每年均有检出.其中金黄色葡萄球菌阳性株中61.29％检出带有肠毒素,增加了潜在的食源性中毒风险;而沙门菌的阳性株分属4个血清型,呈分散性污染.根据统计分析,3年致病菌检出率呈逐年下降趋势,其中2017年最高(14.84％),2019年最低(8.99％),总体夏秋季致病菌检出率高于冬春季.结论 广州市部分网络外卖食品存在致病菌污染,是食源性疾病的潜在风险因素,应继续扩大并加强对外卖食品的专项检验和监督管理.

目的 掌握广州市初中女生监护人对人乳头瘤病毒(human papilloma virus,HPV)疫苗接种意愿及影响因素,为广州市初中女生HPV疫苗免疫接种策略的制定提供参考和依据.方法 采用单纯随机抽样的方法对广州市12～14岁初中女生监护人进行问卷调查,对所得数据进行统计分析,采用Logistic回归方法分析影响广州市初中女生监护人HPV疫苗接种意愿的因素.结果 共回收有效问卷7 391份,90.22％的监护人愿意为孩子接种HPV疫苗,9.78％的监护人不愿接种.不愿接种的主要原因为:担心影响孩子生长发育(42.19％);担心疫苗安全性(41.77％);孩子年纪太小没必要接种(39.70％);对疫苗不了解(36.65％);疫苗的效果未知(31.67％)等.如果广州市开展国产2价HPV疫苗免费接种项目,74.28％的监护人表示愿意接种;3.83％的监护人表示不愿意接种;18.48％的监护人表示学校集体组织即前往接种;3.41％的监护人暂时不确定.农村及城市监护人接种意愿差异无统计学意义(x2=0.53,P＞0.05).多因素Logistic回归分析结果显示:低学历及低收入是影响疫苗接种意愿的主要因素.结论 加强对人群HPV疫苗接种知识的健康教育,消除对接种疫苗的顾虑;推进免费接种策略,推动适龄人群尽早接种疫苗,增强人群接种意识,提高HPV疫苗接种率,从而达到大幅度降低宫颈癌发病率、保护女性健康的目标.

目的 了解广州市某区2011-2020年艾滋病疫情流行特征,为制定相应的针对性防控策略提供依据.方法 从中国疾病预防控制信息系统收集广州市某区2011-2020年累计报告的HIV/AIDS病例数据进行描述性流行病学分析,采用卡方检验分析不同年龄病例感染途径的差异.结果 广州市某区2011-2020年累计报告HIV/AIDS病例688例,其中HIV感染者454例(66.0％),AIDS病例234例(34.0％).报告病例数年均增长11.4％(-22.9％ ～80.7％),呈现先上升后平稳趋势.其中以男性(607例88.2％)、青年人群居多,15～＜25岁、25～＜35岁、35～ ＜45岁病例分别为140例(20.3％)、275例(40.0％)、142例(20.6％).文化程度以大专以上为主(272例,38.6％),检测来源主要为检测咨询(243例,占35.3％),传播途径以性传播为主(675例,98.1％),男男同性传播占58.6％ (403例),且传播途径在不同年龄组差异有统计学意义(x2=93.21,P＜0.01).结论 广州市某区近年来艾滋病疫情呈平稳上升趋势,传播途径以男男同性传播为主.应进一步扩大筛查,加强自愿咨询检测能力建设,深入开展重点人群行为干预.

目的 分析广州市2005-2020年猩红热流行特征和发病趋势,为防控提供依据.方法 运用描述性流行病学方法对广州市2005-2020年猩红热发病数据进行三间分布特征分析.结果 广州市2005-2020年1月猩红热发病呈现波动上升趋势,2020年2月后发病水平较低.每月均有猩红热病例报告,且呈现两个发病高峰,分别出现在3-6月和11月-次年1月;发病人群以3～7岁儿童为主(79.39％);男性发病水平高于女性,男女发病数性别比为1.76:1;白云区和天河区发病数和发病率较其他地区高;报告病例类型以临床诊断病例为主(95.51％).结论 广州市猩红热发病整体处于上升趋势.广州市应大力推进猩红热病原学监测,并提高确诊病例的构成比.

目的 对广州市各区市售乳粉及乳制品中蛋白质与有害因素(包括铅、总汞和总铬)进行风险监测与结果分析,为食品安全风险监测与监督提供科学依据.方法 随机抽检广州市11区市售乳粉及乳制品共十几个品种212宗乳粉及乳制品样品,按照GB 5009.5-2016《中华人民共和国国家标准》和GB 5009.268-2016《食品卫生检验方法 理化部分(一)》进行风险监测与分析.结果 广州市各区城区大型超市市售乳粉及乳制品中蛋白质平均合格率达到100.00％,农贸市场与小商铺乳粉及乳制品中蛋白质平均合格率为93.50％;而有害因素(包括铅、总汞和总铬)结果全部小于国家规定的标准值,合格率高达100.00％.结论 广州市各区市售乳粉及乳制品蛋白质的合格率总体良好,但对婴幼儿乳粉需要重点监测和加强监督.有害因素(包括铅、总汞和总铬)的含量虽然未超过国家标准,但同样需要对金属污染物含量进行定期的风险监管.

目的 分析广州市某高中流感样病例暴发疫情流行病学特征,为学校流感防控提供科学依据.方法 通过现场流行病学调查掌握和分析该起流感样病例暴发疫情病例的基本信息,采集具有典型症状病例的咽拭子进行PCR流感分型检测.结果 本起流感样病例暴发疫情累计报告流感样病例139例,其中男生65例、女生74例,男女性别比例为1∶1.14,罹患率为4.61％(139/3014),病例平均年龄为(16.5±1.6)岁;高二年级累计104例(罹患率为12.32％),高三年级22例(罹患率为3.38％),高一年级13例(罹患率为2.53％),不同年级罹患率差异有统计学意义(x2 =66.124,P＜0.01),但性别分布差异无统计学意义(x2=3.239,P=0.198);本起疫情波及40个班;班级罹患率最高为30.61％,最低为1.75％,不同班级罹患率差异有统计学意义(x2=150.317,P＜0.01);经实验室检测,13份咽拭子中12份A(H3N2)型流感病毒阳性.结论 本起疫情是一起由A(H3N2)型流感病毒所致流感样病例暴发疫情,故流感流行季学校应加强晨检和缺课监测,减少大型集体活动.

目的 了解陆丰市高中学生艾滋病知识、态度、行为情况及影响因素,为学校艾滋病宣传教育及疫情防控提供科学依据,同时为今后的宣传教育效果评估提供基础数据.方法 采取多阶段整群抽样方法,采用自行设计的调查问卷,利用微信扫码功能进行线上自主匿名填写问卷.影响因素单因素分析采用x2检验,多因素分析采用非条件Logistic回归分析.结果 陆丰市高中学生的艾滋病相关知识综合知晓率为27.4％,其中"国八条"的知晓率为40.3％;多因素回归分析结果显示,男生、大年龄组、高年级、父亲学历为大专及以上,学习成绩自评中等及以上,性取向为同性恋或双性恋,同意婚前性行为,参加过学校的相关宣传教育活动为艾滋病知识知晓的促进因素;获得艾滋病相关知识的途径中最高为通过网络,为3076人(78.5％);对艾滋病相关知识的需求中最高为艾滋病传播途径和预防措施,为3514人(89.8％);获得艾滋病相关知识途径的意愿中最高为通过课堂教育,为3164人(80.8％).结论 陆丰市高中学生艾滋病相关知识的知晓率低,防艾基础薄弱,亟需提高学生的知晓率,降低高危行为的发生率.

Objective:To provide scientific basis for the prevention and control of school norovirus infection outbreaks by analyzing the epidemiological characteristics of 12 norovirus infection outbreaks in schools at Liwan District, Guangzhou.Methods:Using descriptive analysis methods, the data on the outbreaks of norovirus infection at Liwan District from January 2004 to January 2021 were collected and analyzed.Results:A total of 12 outbreaks of norovirus infection in schools were reported, with a total of 371 cases, including 366 students and 5 teachers. The total attack rate was 2.99% (371/12 426), and all of which were mild cases, with a male to female ratio of 1.26∶1. They were 2～44 years old. The 12 outbreaks all occurred in autumn, winter, or spring, from October to April. Most outbreaks occurred in January, accounting for 33.33% (4/12). Seven outbreaks occurred in the urban primary schools (58.33%). And the overall attack rate of the urban primary schools was the highest, and was statistically different from those in the other places ( χ2=261.77, P＜0.01). A total of 10 outbreaks of human-to-human transmission (contact or aerosol) accounted for 83.33%, and 2 outbreaks of food-borne transmission accounted for 16.67%. Among them, 7 outbreaks occurred because the vomit in the first case was not cleaned up in time or was not disinfected properly, and 2 food-borne transmission outbreaks were caused by kitchen workers' asymptomatic infections. The main clinical symptoms were vomiting; the proportion of vomiting cases was the highest, and the median of the 12 epidemics was 91.83%. The cases under 13 years old mainly had vomiting, and the ones over 13 years old diarrhea. There were 11 outbreaks of pathogen GⅡ genotype (91.67%), and 1 outbreak of GI type (8.33%). Conclusions:Since 2020, the number of school norovirus outbreaks at Liwan District has increased significantly. School norovirus outbreaks at Liwan District have occurred in autumn, winter, or spring. GⅡ is the main genotype. Urban primary schools are the main sites. Some epidemic reports are not timely. It is recommended to strengthen the health monitoring of teachers, students, and kitchen workers, to implement early detection, isolation, report, and dealing with the outbreak, to improve the ability and efficiency of identifying risk factors for the epidemic, to take rapid and accurate prevention and control measures for the prevention and control of school norovirus outbreaks.

目的 利用GM(1,1)、ARIMA和BP神经网络模型探索肾综合征出血热(hemorrhagic fever with renal syndrome,HFRS)预测预警的最优模型,为广州市的HFRS防控预测预警提供科学建议.方法 系统收集广州市2006-2019年HFRS发病数据,采用GM(1,1)、ARIMA和BP神经网络模型以及混合模型对2006-2016年发病率进行拟合建立HFRS预测已经模型,并对2017-2019年发病率进行预测,通过平均相对误差选取最佳预测预警模型.结果 2006-2019年广州市共报告HFRS病例2 453例,年均发病率1.373/10万,2013年发病率最高,为1.794/10万,2019年发病率最低,为0.954/10万.1-4月共报告1 106例病例,占病例总数的45.08％.ARMIA(0,1,1)(0,1,1)12模型预测的平均相对误差最小为27.75％,GM(1,1)、BP神经网络、BP-GM和BP-ARIMA模型预测的平均相对误差分别为33.280％、27.750％、29.670％、46.210％和46.600％.结论 基于月度数据进行建模的ARIMA模型识别异常值的能力更好,且预测的平均相对误差率最小.

目的 了解2011-2020年广州市荔湾区登革热流行病学特征,为制定控制措施提供依据.方法 从"中国疾病预防控制信息系统"收集2011-2020年广州市荔湾区登革热发病资料,采用描述流行病学方法对登革热的流行病学特征进行分析.结果 2011-2020年广州市荔湾区共报告登革热病例6063例,其中本地病例6021例、输入病例42例,年平均发病率为46.62/10万.最早报告的登革热病例均为输入病例,报告高峰为6-8月,占40.48％(17/42);本地病例报告高峰为9-10月,占85.20％(5130/6021).男女病例比为1∶1.07;年龄分布以20～岁组为主,共4213例,占69.49％;职业分布为家务及待业1275例(占21.03％)、商业服务1189例(占19.61％)、离退人员891例(占14.70％)、其他2708例(占44.66％).42例输入病例中来源于东南亚国家34例,其他地区国家8例.输入病例中均检出4个型别的登革病毒,本地病例中检出3个型别的登革病毒,未检出Ⅳ型.结论 2011-2020年广州市荔湾区登革热仍属于输入疫情引发本地传播的流行模式.输入病例早期及时发现、核酸排查、隔离治疗,为减少登革热本地病例发生的主要措施.

目的 了解广州市生活饮用水水质卫生状况,为保证饮水水质安全提供科学依据.方法 按照《生活饮用水标准检验方法》(GB/T 5750-2006)对2018年广州市市政供水、乡镇水厂、农村饮水安全工程和分散式供水的水质进行监测,依据《生活饮用水卫生标准》(GB 5749-2006)对监测结果进行评价,比较不同类型饮用水的水质卫生状况.结果 2018年广州市市政供水、乡镇水厂、农村饮水安全工程和分散式供水的出厂水合格率分别为100.00％、96.88％、14.29％和7.69％,市政供水和乡镇水厂出厂水合格率均高于农村饮水安全工程和分散式供水,差异均有统计学意义(x2市政vs农村=80.384,x2乡镇vs农村=118.760,x市政vs分散=72.839,x2乡镇vs分散=102.749,P＜0.01).农村饮水安全工程和分散式供水的主要不合格项目是微生物指标和pH值.管网末梢水的合格率为94.41％,二次供水合格率为84.30％,主要不合格项目为游离余氯、菌落总数、浑浊度和肉眼可见物.结论 广州市农村饮水安全工程和分散式供水的水质卫生状况较差,应加强对农村供水的水质监管和安全卫生管理.

Rotavirus is considered as the most important viral agent of acute gastroenteritis in children less than 5 years old worldwide. Nosocomial rotavirus infection seems to be responsible for around 25% of all rotavirus-related hospitalizations. Nosocomial rotavirus gastroenteritis is important because it significantly prolongs hospital stay and increases the social and economic burden of the hospitalization. Recently, there were sporadic diarrhea cases in the department of pediatrics of a hospital in Guangzhou, southern China. In order to find out the causative agent, sources, and risk factors, we used the retrospective investigation method to collect the diarrhea situation of hospitalized cases in recent one month. As a result, a total of 6 children with diarrhea and positive for rotavirus in feces were found in pediatric inpatients in the past month, among which three cases had been discharged and three cases were in hospital. Five of 6 children were found vaccinated with only one dose Lanzhou lamb rotavirus vaccine (LLR) two years ago. The hospital quickly opened up isolation wards for three positive children. These children were not hospitalized for gastrointestinal diseases, and common infectious diseases were excluded before admission. According to the investigation, children in different wards often visit each other during hospitalization, which may lead to cross infection. We carried out monitoring and sampling of hospital environment, all children and medical staff in pediatric inpatient department. The samples were sent to Guangzhou Center for Disease Control and prevention for nucleic acid detection of common enteroviruses using RTPCR, including Norovirus, Adenovirus, Astrovirus and Rotavirus. The test results showed that the smear samples of bed handrail and toilet in the ward of the three discharged child and three rectal swab samples from hospitalized children tested positive for Rotavirus. Then, we continued to expand the sampling range and the smear samples of three wards environment tested positive for Rotavirus, including the air outlet and return air outlet of air conditioner, door handles and bed rails, toilets and mops in the isolation area. All the samples from medical staffs were tested negative for Rotavirus. Three samples from cases were genotyped for both VP7 and VP4. Phylogenetic analysis indicated that the Rotavirus strains detected in three samples were all Rotavirus G8P[8] (Figures 1 and 2). This study reports a hospital acquired rotavirus acute gastroenteritis event in a pediatric unit. We speculate that it may be caused by close contact between children and failure of disinfection since we still detected positive for rotavirus in the environment after the implementation of routine disinfection in the hospital. Frequent visits between different wards may play a role in increasing the chance of rotavirus transmission. Rotavirus, a double-stranded RNA virus belongs to the family Reoviridae, and children infected with rotavirus may experience severe watery diarrhea (often with vomiting), mild-to-moderate fever, and abdominal pain. Previous studies showed that the five genotypes G1P[8], G2P[4], G3P [8], G4P[8], and G9P[8] Group A rotavirus cause up to 75% of human Group Rotavirus infections worldwide, which is similar to the study in China. Rotavirus genotype G8 infection is common in bovines but rarely occurs in humans; however, the G8 strains have been reported frequently among children in African countries. The result indicated that the G8 strains might be recently introduced into China. The effectiveness of current rotavirus vaccines not against the unusual G8P[8] subtype, for which was virtually not targeted in the vaccines. The emerging strain and incomplete vaccination may explain the failure of vaccination protection. However, epidemiological surveillance data on G8P[8] in crowd settings such as schools and health-care facilities is scarce in China. Continuing etiological surveillance is required to monitor the circulating strains and the virulence in humans. Be alert to the epidemic caused by the new rotavirus subtype in COVID-19’s prevention and control. The improvement of the whole course immunization coverage rate of rotavirus vaccine should be enhanced meanwhile.

As a continuous antenna, the leaky coaxial cable (LCX) is widely used in wireless communication of closed or semi-closed areas such as the subway, mine, tunnel, etc. Usually, LCX networks are required in coal mines. Its channel characteristics are of great significance to mobile communication and mine safety. This paper presents an effective channel modeling and optimization method that combines the state transition and the particle swarm optimization (PSO) algorithms for the LCX network. First, a channel model can be established with a few parameters based on the state transition method, which can describe the complex transfer function of the LCX network; then, taking the transfer characteristics of the LCX network as the optimization objective, which should be consistent with the measured results. And the established objective function is optimized and designed with the PSO algorithm. Finally, the proposed method is validated by comparing the measured results and the model-based simulations on two test LCX networks. The experimental results show that the absolute error between the proposed model and the measurement model is less than that of other models at any frequency point. The proposed model can accurately obtain all responses between point-to-point channels at one time. It will help to accurately obtain the performance of different LCX networks and help to detect and locate faults in future studies.

目的 分析总结广州市荔湾区2015-2020年流行性感冒(流感)流行特征,为全区流感防控提供科学依据.方法 使用中国疾病预防控制信息系统导出广州市荔湾区流感监测相关数据,使用描述性流行病学方法分析荔湾区流感流行特征.结果 广州市荔湾区2015-2020年累计报告流感样病例15 090例,其中男性8 062例、女性7 028例,男女性别比例为1.15∶1;2019年报告病例数为历年最多(7 562例),占2015-2020年报告病例总数的50.11％;2019年12月报告发病率为近5年最高(218.144 3/10万);各年龄中0～4岁组报告流感样病例数各年均为最高,其次为5～9岁组;各年龄组中男性病例数均多于女性,20～29岁组、30～39岁组、40～49岁组、50～59岁组则为女性病例多于男性;各年报告病例数均为男性多于女性;2015-2020年流感病疾病构成比例分别为8.80％、12.84％、13.28％、22.55％,46.40％、30.07％;2015-2020年累计报告流感样病例暴发疫情20起;病原学监测显示,总体阳性率为8.85％(554/6 258),阳性毒株主要为A(H1N1)型208份、A(H3N2)型169份、B(Victoria)型90份、B(Yamagata)型87份.结论 广州市荔湾区流感感染主要人群为0～9岁婴幼儿和儿童,呈季节性流行,主要为春季和冬季,不同病毒亚型交替流行.

目的 分析2010-2019年广州郊区6区登革热本地疫情流行趋势,为制订防控策略提供依据.方法 通过国家传染病监测信息报告管理系统收集病例信息,对每个登革热本地病例和暴发疫情开展现场流行病学调查并完成调查处置报告.对收集的疫情资料进行描述性分析,并对2010-2013年和2015-2019年疫情资料分组,对比发病水平、波及范围、疫情强度、病毒型别等方面的变化趋势.结果 相比2010-2013年,2015-2019年广州市郊区登革热总体疫情规模呈上升趋势,病例数上升7.82倍;本地疫情波及范围从2010-2013年的26个街镇扩大到2015-2019年的60个街镇;疫情强度从2010-2013年的部分散发和个别暴发进展为2015-2019年的普遍散发和部分暴发甚至较大暴发,此外,重症死亡病例增多,本地疫情每年的病毒型别也从1种进展为至少2种.结论 近年来,广州郊区登革热疫情强度明显上升,已成为广州登革热高风险区域,需加强郊区的登革热防控以遏制疫情的扩散.

目的 了解医院洁净手术部空气消毒现况和日常管理情况,揭示洁净技术维护与空气消毒质量之间的关联,为规范开展洁净手术室维护提供依据.方法 通过问卷调查与现场采样检测相结合的方式对广州市12家三甲医院进行研究,通过关联规则分析探讨空气检测质量与消毒技术配备和维护之间的关系,通过聚类分析对调查医院进行风险分类.结果 12家医院共抽检洁净手术室19间,中心区平均合格率75.2％;周边区平均合格率64.2％;关联规则发现最终确定14条规则,院感人员配备充足、洁净技术按照规范标准进行维护与中心手术区浮游菌检测合格存在关联.层次聚类结果显示,在距离为4的情况下可将12家医院分类三类.结论 洁净手术室中心区和周边区均存在不同程度的污染,日常运行维护与手术室空气污染之间存在关联.

目的 通过优化衍生条件,建立基于气相色谱串联三重四极杆质谱联用仪(GC-MS/MS)测定蔬菜中二硫代氨基甲酸酯(盐)类农药残留的方法.方法 样品匀浆,经40％氯化亚锡-盐酸溶液(SnCl2-HC1)衍生后,用正己烷萃取,再用GC-MS/MS测定正己烷中的CS2的量,并测定标准系列溶液,绘制标曲;同时用福美双标准液测试转化率.结果 方法浓度为0.02～10 mg/L,线性相关系数为0.9999,精密度为1.82％～3.86％,回收率为98.2％～108.4％,检出限为0.001 mg/kg,且福美双的转化率为90.4％～107.6％.对广州市212份蔬菜样品进行检测,超标率仅为0.5％.结论 该方法有优秀的宽线性、较好的精密度和准确度.广州市蔬菜样品中二硫代氨基甲酸酯(盐)类农药带来的食品安全风险极低.