Tularemia in Bursa, Turkey: 205 cases in ten years

Tularemia is a zoonotic disease caused by the coccobacillus F. tularensis. Small epidemics and sporadic cases were seen around Bursa since November 1988. In this study, a total of 205 cases of tularemia were observed. All the cases were diagnosed on clinical, bacteriological and serological grounds. The epidemics were thought to be waterborne. The majority of the patients were young and female. In most of the cases the disease presented itself in oropharyngeal form (83%). Analysing sera from the patients with microagglutination method demonstrated that titers were 1:160 in approximately 85% of the cases, including the ones in subclinical form. Five of ten patients from who the bacteria was isolated were seronegative. Streptomycin was given to the most of the patients by combining with tetracycline, doxycycline or chloramphenicol. The early administration of these antibiotics (before the third week of disease) was found to be much more effective to resolve the infection. As a result, the main mode of transmission of F. tularensis is waterborne in our region. In our region, tularemia should be considered in differential diagnosis for the cases with fever, tonsillopharyngitis and cervical lymphadenopathy to make an early diagnosis and to design relevant treatment.     

新疆水源性隐孢子虫的检测

目的检测新疆15个城市自来水和河水隐孢子虫污染情况。方法采集水样,分别应用改良美国环保局(EPA)1622法及巢式PCR(nested-PCR)方法进行检测。1)改良EPA1622法:水样经微孔滤膜抽滤、淘洗,磁抗体分离法分离纯化后免疫荧光染色鉴定。2)Nested-PCR法:用试剂盒提取纯化的隐孢子虫卵囊基因组DNA,针对隐孢子虫小亚单位核糖体RNA(18SrRNA)部分基因,依据文献设计并合成引物,用巢式PCR扩增,产物纯化后经SspⅠ及VspⅠ单酶切,并进行RFLP分析。结果2种方法检测新疆15个地区的自来水隐孢子虫卵囊均为阴性,改良EPA1622法检测乌鲁木齐市、昌吉市、伊宁市和吐鲁番市的河水隐孢子虫卵囊阳性。巢式PCR检测乌鲁木齐市和伊宁市水样,均扩增出约830 bp的特异片段,RFLP初步鉴定为小鼠隐孢子虫基因;昌吉市和吐鲁番市河水水样PCR检测阴性。结论新疆乌鲁木齐市、伊宁市河水检出隐孢子虫,初步鉴定为小鼠隐孢子虫。而当地的饮用水未受污染。     

Recreational exposure to microcystins during algal blooms in two California lakes

We conducted a study of recreational exposure to microcystins among 81 children and adults planning recreational activities on either of three California reservoirs, two with significant, ongoing blooms of toxin-producing cyanobacteria, including Microcystis aeruginosa (Bloom Lakes), and one without a toxin-producing algal bloom (Control Lake). We analyzed water samples for algal taxonomy, microcystin concentrations, and potential respiratory viruses (adenoviruses and enteroviruses). We measured microcystins in personal air samples, nasal swabs, and blood samples. We interviewed study participants for demographic and health symptoms information. We found highly variable microcystin concentrations in Bloom Lakes (<10 μg/L to >500 μg/L); microcystin was not detected in the Control Lake. We did not detect adenoviruses or enteroviruses in any of the lakes. Low microcystin concentrations were found in personal air samples (<0.1 ng/m³ [limit of detection]-2.89 ng/m³) and nasal swabs (<0.1 ng [limit of detection]-5 ng). Microcystin concentrations in the water-soluble fraction of all plasma samples were below the limit of detection (1.0 μg/L). Our findings indicate that recreational activities in water bodies that experience toxin-producing cyanobacterial blooms can generate aerosolized cyanotoxins, making inhalation a potential route of exposure. Future studies should include collecting nasal swabs to assess upper respiratory tract deposition of toxin-containing aerosols droplets.     

2009年成都市水性疾病及哨点监测结果分析

目的了解成都市介水传染病流行状况和特征,做好水性疾病预警,同时掌握其分布规律和流行趋势,探讨水性疾病的控制策略。方法收集成都市2009年经水传播的肠道传染病及哨点医院症状监测结果,数据用χ^2检验进行统计学分析。结果成都市水性疾病构成主要以其他感染性腹泻和细菌性痢疾为主,两者占总发病数的93.01%,除1～3月发病率较低外,其他月份发病率均较高,但无统计学差异（5～12月发病率P〉0.05）;发病人群以5岁以下散居儿童为主,哨点医院进行症状监测年发生率与成都市水性疾病年发生率相比无显著性差异（P〉0.05）。结论 5岁以下散居儿童为水性疾病的高危人群,水性疾病的控制可以其他感染性腹泻和细菌性痢疾为主进行相关性研究,而选择合适的医院门诊作为监测水性疾病的哨点,是一种切实可行的监测模式。     

POU水过滤器对军团菌属及其他水源性病原菌的清除功效

目的在上海地区自来水水质条件下,评估POU水过滤器在临床实际使用中清除军团菌属及其他病原菌的功效。方法在医院移植监护病房的3个水龙头上分别安装POU水过滤器(Aquasafe AQ14F1S,孔径0.2μm,颇尔公司)和前置过滤装置(孔径:1.2μm,以去除自来水中的颗粒状杂质),每2周更换1次,共18周;每3～4 d检测水样,包括打开水龙头立即采集的POU过滤水,打开水龙头冲洗30 s的POU过滤水,未经过滤的自来水,经前置过滤器过滤的自来水;4种样本均用标准培养方法计数异养菌总数、军团菌属、分枝杆菌属、铜绿假单胞菌和丝状真菌的数量,并采用单因素方差分析进行数据统计和分析。结果共采集229份水样,100份未过滤水中19份分离到各种血清型的军团菌属;自来水中军团菌属、分枝杆菌属、铜绿假单胞菌和丝状真菌的平均浓度分别为:1.0×103、4.9×1023、5 CFU/L和26.5 CFU/L;所有经POU过滤的水样中均未发现军团菌属、分枝杆菌属、铜绿假单胞菌和丝状真菌;POU水过滤器对异养菌的清除率>90%,自来水样本与预过滤水样本中细菌浓度差异无统计学意义。结论 POU水过滤器可彻底清除嗜肺军团菌、分枝杆菌属、铜绿假单胞菌和丝状真菌,有利于降低获得性医院感染的潜在危险。     

饮用水常规指示菌与介水传染病相关性研究

目的研究GB 5749—2006《生活饮用水卫生标准》中常规监测指示菌与介水传染病之间的相关性。方法从公共卫生科学数据中心获取2014年全国介水传染病发病数据和饮用水常规指示菌监测数据;采用主成分分析对全国22个省市常规指示菌合格率作排名和分级;对常规指示菌与介水传染病及常规指示菌间的相关性采用Spearman偏相关分析。结果在22个省市饮用水常规指示菌合格率分级中,黑龙江省、江苏省、北京市和河北省等级较高。枯水期间除总大肠菌群水平与副伤寒发病率呈正相关(P0.05)外,其他指示菌与疾病之间均无显著相关性;4种常规指示菌间均两两呈正相关(P0.05)。丰水期间除总大肠菌群水平与伤寒、副伤寒发病率呈正相关(P0.05)外,其他指示菌与疾病之间无显著相关性;除大肠埃希菌与菌落总数无显著相关性外,其他常规指示菌间两两呈正相关。结论 GB 5749—2006中的常规指示菌与介水传染病相关性并不显著,建议进一步进行常规指示菌与介水传染病相关性的定量研究及探寻新型指示菌。     

Quantifying tap-to-household water quality deterioration in urban communities in Vellore,India: The impact of spatial assumptions

Municipal water sources in India have been found to be highly contaminated, with further water quality deterioration occurring during household storage. Quantifying water quality deterioration requires knowledge about the exact source tap and length of water storage at the household, which is not usually known. This study presents a methodology to link source and household stored water, and explores the effects of spatial assumptions on the association between tap-to-household water quality deterioration and enteric infections in two semi-urban slums of Vellore, India. To determine a possible water source for each household sample, we paired household and tap samples collected on the same day using three spatial approaches implemented in GIS: minimum Euclidean distance; minimum network distance; and inverse network-distance weighted average. Logistic and Poisson regression models were used to determine associations between water quality deterioration and household-level characteristics, and between diarrheal cases and water quality deterioration. On average, 60% of households had higher fecal coliform concentrations in household samples than at source taps. Only the weighted average approach detected a higher risk of water quality deterioration for households that do not purify water and that have animals in the home (RR = 1.50 [1.03, 2.18], p = 0.033); and showed that households with water quality deterioration were more likely to report diarrheal cases (OR = 3.08 [1.21, 8.18], p = 0.02). Studies to assess contamination between source and household are rare due to methodological challenges and high costs associated with collecting paired samples. Our study demonstrated it is possible to derive useful spatial links between samples post hoc; and that the pairing approach affects the conclusions related to associations between enteric infections and water quality deterioration.     

Improved health outcomes in urban slums through infrastructure upgrading

The world is rapidly urbanizing with over half the population now living in urban areas. As the urban population grows, so does the proportion of these persons living in slums where conditions are deplorable. These conditions concentrate health hazards leading to higher rates of morbidity and mortality. This growing problem creates a unique challenge for policymakers and public health practitioners. While the Millennium Development Goals (MDGs) aim to address these conditions and standards for water and sanitation as well as pertinent health outcomes, little evidence on interventions exists to guide policymakers. Upgrades in slum household water and sanitation systems have not yet been rigorously evaluated to demonstrate whether there is a direct link to improved health outcomes. This study aims to show that slum upgrading as carried out in Ahmedabad, India, led to a significant decline in waterborne illness incidence. We employ a quasi-experimental regression model using health insurance claims (for 2001–2008) as a proxy for passive surveillance of disease incidence. We found that slum upgrading reduced a claimant’s likelihood of claiming for waterborne illness from 32% to 14% and from 25% to 10% excluding mosquito-related illnesses. This study shows that upgrades in slum household infrastructure can lead to improved health outcomes and help achieve the MDGs. It also provides guidance on how upgrading in this context using microfinance and a public–private partnership can provide an avenue to affect positive change.     

Trends in recent waterborne and foodborne disease outbreaks in South Korea, 2015–2019

ObjectivesThis study analyzed trends in foodborne and waterborne diseases in South Korea between 2015 and 2019.MethodsThe data consisted of information on outbreaks of waterborne and foodborne infectious diseases reported through the Korea Centers for Disease Control and Prevention (KCDC) system. We analyzed the trends and epidemiological aspects of outbreaks by month, place of occurrence, and causative pathogens in this observational study.ResultsThe number of outbreaks has steadily increased over the last 5 years, but the number of cases per outbreak has followed a decreasing trend. Incidence at daycare centers and preschools has been steadily increasing over consecutive years.ConclusionThe steady number of patients and decreasing number of cases per outbreak, even as the number of outbreaks has been increasing, suggest that the KCDC’s professional management system is operating effectively. It is necessary to continue improving the objectivity and efficiency of the management system and to carefully examine the increasing number of outbreaks in smaller-scale group catering facilities, such as daycare centers and preschools. Outbreaks can be prevented by closely examining those caused by unidentified pathogens and group outbreaks caused by other diseases, identifying problems, and supplementing the management system.