An outbreak of Norwalk-like gastroenteritis associated with contaminated drinking water at a caravan park

Abstract: During the 1989 Christmas holiday period, a large outbreak of gastroenteritis occurred among persons staying at a caravan park in southern New South Wales. Review of local hospital records found that 77 per cent of patients presenting with infective diarrhoea between 29 December and 3 January had stayed at the caravan park. In a retrospective cohort study we compared rates of illness among caravan park patrons exposed to different water sources. Stools were tested for pathogens and convalescent sera for viral antibodies. Rain and reticulated river water sampled from the caravan park were tested for bacteria and viruses. Of 351 persons interviewed at the caravan park, 305 (87 per cent) reported an illness characterised by diarrhoea, vomiting and abdominal pain. Of 196 persons who used reticulated river water for drinking or ablutions, 175 (89 per cent) became ill compared with 47 of 72 persons (65 per cent) who did not use this water (relative risk 1.4, 95 per cent confidence interval 1.2 to 1.6). The outbreak was probably caused by a 27–28 nm small round structured virus found in the stool from one ill person. High levels of faecal coliforms in the reticulated river water and enterovirus in sediment samples suggest that the outbreak was caused by sewage contaminating the reticulated river water through a break in the pipe directly over the underground water tanks. To prevent such outbreaks, poor water and sewerage system layouts should be avoided and nonpotable water should be clearly labelled. Where feasible, all camping-ground water should stem from town supplies.     

Psychiatric diagnoses of medical service users: evidence from the Epidemiologic Catchment Area Program.

Based on data from the five sites of the National Institute of Mental Health-sponsored Epidemiologic Catchment Area (ECA) Program, this paper examines the prevalence of psychiatric disorder among recent medical service users versus nonusers, with a particular focus on affective disorders, substance abuse/dependence, and phobias. The rate of current Diagnostic Interview Schedule (DIS) disorders among medical users in all five ECA sites is 21.7 per cent (slightly higher than general population rates) versus 16.7 per cent among nonusers; there is generally no difference between users and nonusers with past DIS diagnoses. Affective disorders were among the most common mental disorders of medical service users, especially among females, with little variation between sites: females: users: 6.9 per cent to 9.3 per cent, nonusers: 3.4 per cent to 6.4 per cent, and males: users: 3.3 per cent to 6.5 per cent, nonusers: 1.2 per cent to 4.1 per cent. Rates of phobias among persons using medical services are also higher than among nonusers. Substance abuse disorders are at least as common among persons who use medical services (8 per cent to 14 per cent of male users) as among those who do not (9 per cent to 11 per cent of male nonusers). The high rates of affective disorders among women and of substance abuse among male medical service users underscore the need to increase the ability of general medical practitioners to recognize and manage or refer these conditions.     

Treated incidence of mental disorders in a prepaid group practice setting.

We followed a cohort of 7,666 individuals enrolled continuously for five years in a prepaid group practice in Columbia, Maryland. Incidence rates of all diagnosed mental disorders were estimated at approximately 3.7 per cent, lower for adolescents and children (about 3 per cent), higher for adult males aged 20-49 (4.3 per cent), and highest for adult females (5.8 per cent). Diagnoses are primarily for acute mental disorders and show a tendency to recur at fairly high rates.     

Characteristics of sheltered homeless families.

To describe the characteristics of homeless families, we interviewed 80 homeless mothers and 151 children living in 14 family shelters in Massachusetts (two-thirds of the shelters in the state). Ninety-four per cent of the families were headed by women, 91 per cent were on AFDC (aid to families with dependent children), with twice as many as the state average having been on AFDC for at least two years; most had long histories of residential instability. Although 60 per cent had completed high school, only a third had worked for longer than one month. One-third of the mothers reported having been abused during their childhood, and two-thirds had experienced a major family disruption. At the time of the interview, almost two-thirds either lacked or had minimal supportive relationships and one-fourth of these named their child as the major support. Eighteen mothers were involved with the Department of Social Services because of probable child abuse or neglect. Seventy-one per cent of the mothers had personality disorders. In contrast to many adult homeless individuals, however, deinstitutionalized persons or those suffering from psychoses were not overrepresented. About 50 percent of the homeless children were found to have developmental lags, anxiety, depression, and learning difficulties, and about half required further psychiatric evaluation. Two-thirds described housing and social welfare agencies as not helpful. Given the many serious problems of the mothers and the difficulties already manifested by their children, comprehensive psychosocial and economic interventions must be made to interrupt a cycle of extreme instability and family breakdown.     

Prevalence of mood disorders according to dsm-iii-r criteria in the community elderly residents in Japan

The prevalence rates of mood disorders according to the DSM- III -R criteria in the community elderly were investigated with structured interviews conducted by psychiatrists. The subjects were 1,965 randomly selected residents aged 65 years or more who lived in Nagai City, Japan. In the first phase, a questionnaire including the short form of the Geriatric Depression Scale (GDS) was distributed to all subjects. In the second phase, all persons scoring 6 points or more on the GDS and approximately half as many of these persons randomly selected from the remaining respondents scoring 5 points or less were examined by psychiatrists using the A and D modules of the Structured Clinical Interview for DSM-III-R. The 1-month prevalence rates of major depression and bipolar disorder were estimated to be 0.9% and 0.0%, and the current prevalence of dysthymia was estimated to be 0.5%. By using additional unstructured clinical interviews, we also found the prevalence rates of adjustment disorder with depressed mood and other types of depression to be 3.8% and 2.5%. For these categories of depression, prevalence rates did not differ significantly by sex or age group, except that the prevalence of adjustment disorder with depressed mood was significantly higher in women than in men.     

Estimating HIV incidence rates from age prevalence data in epidemic situations.

We present a method of estimating HIV incidence rates in epidemic situations from data on age-specific prevalence and changes in the overall prevalence over time. The method is applied to women attending antenatal clinics in Hlabisa, a rural district of KwaZulu/Natal, South Africa, where transmission of HIV is overwhelmingly through heterosexual contact. A model which gives age-specific prevalence rates in the presence of a progressing epidemic is fitted to prevalence data for 1998 using maximum likelihood methods and used to derive the age-specific incidence. Error estimates are obtained using a Monte Carlo procedure. Although the method is quite general some simplifying assumptions are made concerning the form of the risk function and sensitivity analyses are performed to explore the importance of these assumptions. The analysis shows that in 1998 the annual incidence of infection per susceptible woman increased from 5.4 per cent (3.3-8.5 per cent; here and elsewhere ranges give 95 per cent confidence limits) at age 15 years to 24.5 per cent (20.6-29.1 per cent) at age 22 years and declined to 1.3 per cent (0.5-2.9 per cent) at age 50 years; standardized to a uniform age distribution, the overall incidence per susceptible woman aged 15 to 59 was 11.4 per cent (10.0-13.1 per cent); per women in the population it was 8.4 per cent (7.3-9.5 per cent). Standardized to the age distribution of the female population the average incidence per woman was 9.6 per cent (8.4-11.0 per cent); standardized to the age distribution of women attending antenatal clinics, it was 11.3 per cent (9.8-13.3 per cent). The estimated incidence depends on the values used for the epidemic growth rate and the AIDS related mortality. To ensure that, for this population, errors in these two parameters change the age specific estimates of the annual incidence by less than the standard deviation of the estimates of the age specific incidence, the AIDS related mortality should be known to within +/-50 per cent and the epidemic growth rate to within +/-25 per cent, both of which conditions are met. In the absence of cohort studies to measure the incidence of HIV infection directly, useful estimates of the age-specific incidence can be obtained from cross-sectional, age-specific prevalence data and repeat cross-sectional data on the overall prevalence of HIV infection. Several assumptions were made because of the lack of data but sensitivity analyses show that they are unlikely to affect the overall estimates significantly. These estimates are important in assessing the magnitude of the public health problem, for designing vaccine trials and for evaluating the impact of interventions.     

Annual report of the National Influenza Surveillance Scheme, 2001.

Surveillance of influenza in Australia in 2001 was based on data from national and state-based sentinel practice consultations for influenza-like illness, laboratory isolations of influenza virus and absenteeism rates from a national employer. In 2001, laboratory-confirmed influenza became a notifiable disease and was reported to the National Notifiable Diseases Surveillance System (NNDSS). Influenza A was the dominant type, 81 per cent of which were subtype H1N1 and 19 per cent were subtype H3N2. The influenza A (H1N1) analysed were all A/New Caledonia/20/99-like strains. The H3N2 isolates were antigenically similar to the reference strain A/Moscow/10/99 and the vaccine strain A/Panama/2007/99. The influenza B isolates, which made up only 10 per cent of all isolates, were mainly B/Sichuan/379/99-like strains but 10 per cent of isolates were more closely related to B/Harbin/7/94-like viruses, which circulated in previous years. The Australian 2001 influenza vaccine represented a good match for the circulating viruses and 77 per cent of persons over 65 years in Australia were vaccinated in 2001.     

Northeastern Ohio trauma study: I. Magnitude of the problem.

This study measured the incidence of cause-specific trauma in the Cleveland and Lorain-Elyria Standard Metropolitan Statistical Areas (SMSAs), population 2.2 million, as reported to hospital emergency departments (ED). Cases were selected according to a stratified probability sampling plan (N = 9268). The participating hospitals accounted for 97.6 per cent of 903,346 ED visits in 1977; 52 per cent of these visits were for trauma (ICDA-8 E800-E999). The trauma incidence rate was 197 per 1,000 population. The six leading causes of injury were: falls, 24.4 per cent; cut/piercing injury, 14.2 per cent; striking or struck by object, 13.8 per cent; motor vehicle collisions (MVC), 11.6 per cent; overexertion/strain, 8.2 per cent; and assault, 4.3 per cent. Only falls, MVCs, and assaults were leading causes of both injury and death. The injury incidence rates for vehicular crashes and assault were 1.4 and 3.8 times higher, respectively, than the official incidence rates for these SMSAs. These differences point to a significant underreporting of data needed for public health decision making. Because data were not collected on cases treated outside the participating hospitals, the incidence rates reported here represent a conservative estimate of the magnitude of the problem.     

Incidence and costs of incidental appendectomy as a preventive measure.

Statewide hospital discharge data in South Carolina for the period 1979-81 were used to evaluate the effectiveness of the incidental appendectomy performed as a preventive measure. The occurrence of incidental appendectomy exceeded that of appendicitis treated by appendectomy, with population-based rates of 1.13/1,000 and 0.97/1,000 person-years, respectively. Over 64 per cent of appendicitis cases occurred in persons under 25 years of age while 74 per cent of incidental appendectomies occurred in persons age 25 and over. Extrapolating to the nation, the data suggest that 254,250 incidental appendectomies might prevent 3,382 future cases of hospitalized appendicitis. The cost of the prevented cases is estimated as $6,764,000. The cost of the incidental appendectomies would be $20,340,000 if as many as 10 per cent of surgeons' fees were separately charged and twice as much if twice as many were so charged. Information on charges for incidental appendectomies is not readily available.     

An outbreak of waterborne giardiasis associated with heavy water runoff due to warm weather and volcanic ashfall

From mid-June through early August 1980, an outbreak of gastrointestinal illness in Red Lodge, Montana affected approximately 780 persons, as estimated from attack rates of 33 per cent and 15 per cent in urban and rural residents, respectively. Giardia lamblia was identified in stool specimens from 51 per cent of 47 persons with a history of untreated gastrointestinal illness and in 13 per cent of 24 specimens from asymptomatic persons (p = .00045, Fisher's Exact Test). The epidemic curve was bimodal with peaks in mid-June and mid-July. Each peak occurred about three weeks after an episode of very heavy water runoff resulting from warm sunny weather and snow darkened by ashfall from the Mt. St. Helens volcanic eruption of May 18, 1980. Unfiltered and inadequately chlorinated surface water was supplied by the city water system, which was implicated as the vehicle of transmission in the outbreak. Water systems providing unfiltered surface water are more likely to become contaminated during periods of heavy water runoff.     

Disability Associated with Comorbid Anxiety Disorders in Women with Chronic Physical Illness in Ontario,Canada

ABSTRACT

Anxiety disorders are more prevalent in individuals with chronic physical illness compared to individuals with no such illness, and about twice as prevalent in women as in men. This study used data collected in the 2005 Canadian Community Health Survey (21,198 women and 20,478 men) to examine factors associated with comorbid anxiety disorders and to assess the relation of these disorders on short-term disability and suicidal ideation. Comorbid anxiety disorders were more prevalent among women who were young, single, poor, and Canadian-born, and among women with chronic fatigue syndrome; fibromyalgia, bowel disorder or stomach or intestinal ulcers, or bronchitis had the highest rates of anxiety disorders. The presence of comorbid anxiety disorders was significantly associated with short-term disability, requiring help with instrumental daily activities, and suicidal ideation. Our findings underscore the importance of early detection and treatment of anxiety disorders in the physically ill, especially those who also suffer from mood disorders.     

Disability associated with comorbid anxiety disorders in women with chronic physical illness in Ontario, Canada

Anxiety disorders are more prevalent in individuals with chronic physical illness compared to individuals with no such illness, and about twice as prevalent in women as in men. This study used data collected in the 2005 Canadian Community Health Survey (21,198 women and 20,478 men) to examine factors associated with comorbid anxiety disorders and to assess the relation of these disorders on short-term disability and suicidal ideation. Comorbid anxiety disorders were more prevalent among women who were young, single, poor, and Canadian-born, and among women with chronic fatigue syndrome; fibromyalgia, bowel disorder or stomach or intestinal ulcers, or bronchitis had the highest rates of anxiety disorders. The presence of comorbid anxiety disorders was significantly associated with short-term disability, requiring help with instrumental daily activities, and suicidal ideation. Our findings underscore the importance of early detection and treatment of anxiety disorders in the physically ill, especially those who also suffer from mood disorders.     

The contribution of working conditions and social support to the onset of depressive and anxiety disorders among male and female employees

Poor working conditions may be an important source of stress and may therefore contribute to the development of depressive and anxiety disorders. Social support may act as a buffer and protect against the development of depression or anxiety in the face of poor working conditions. With longitudinal data from the Netherlands Mental Health Survey and Incidence Study (NEMESIS), the effect of working conditions and social support on the incidence of depressive and anxiety disorders was examined among 2646 working men and women, aged 18 through 65 years. Three dimensions of self reported working conditions were assessed: psychological demands, decision latitude and job security. Social support was assessed through validated scales for daily emotional support. About 10.5% of working women and 4.6% among working men developed an incident depressive and/or anxiety disorder over 2 years. Psychological demands predicted the incidence of depressive and anxiety disorders in both men and women (RR per score increase=2.29, 95% CI: 1.44-3.63), whereas decision latitude and job security did not. Social support protected against the incidence of depressive and anxiety disorders. This effect was stronger for men compared to women. Social support did not buffer the unfavorable mental effect of working conditions. Women were more likely to report low levels of decision latitude, whereas men reported higher psychological demands. Working conditions did not explain sex differences in the incidence of depressive and anxiety disorders.     

Mental health and social characteristics of the homeless: a survey of mission users.

Selected mental health and social characteristics of 51 homeless persons drawn as a probability sample from missions are compared to those of 1,338 men aged 18-64 years living in households from the NIMH Epidemiologic Catchment Area survey conducted in Eastern Baltimore. Differences between the two groups were small with respect to age, race, education, and military service but the differences in mental health status, utilization patterns, and social dysfunction were large. About one-third of the homeless scored high on the General Health Questionnaire which measures distress. A similar proportion had a current psychiatric disorder as ascertained by the Diagnostic Interview Schedule (DIS), with the homeless exhibiting higher prevalence rates in every DIS/DSM III diagnostic category compared to domiciled men. Homeless persons reported higher rates of hospitalization than household men for both mental (33 per cent vs 5 per cent) and physical (20 per cent vs 10 per cent) problems but a lower proportion received ambulatory care (41 per cent vs 50 per cent). Social dysfunction among the homeless was indicated by fewer social contacts and higher rates of arrests as adults than domiciled men (58 per cent vs 24 per cent), including multiple arrests (38 per cent vs 9 per cent) and felony convictions (16 per cent vs 5 per cent). Implications of these findings are discussed in terms of research and health policy.     

Waterborne Gastroenteritis due to the Norwalk Agent: Clinical and Epidemiologic Investigation

An outbreak of gastroenteritis occurred at a Pennsylvania summer camp in July 1978. Symptoms included abdominal pain (81 per cent), nausea (72 per cent), and vomiting (53 per cent); upper respiratory infection symptoms occurred in 35 per cent of the campers. Illness was associated with consumption of five or more glasses of water or water-containing beverages. Stool cultures from affected persons were negative for bacterial pathogens; however, a fourfold or greater rise to the Norwalk agent was demonstrated in serum samples of three of three ill persons tested and in none of eight controls (p < .02). Campers ill during the first session who were also present during the second session did not become ill during the second session (p < .001). (Am J Public Health 1982; 72:72-74.)     

心理社会因素对HIV阳性者情绪障碍的影响

目的分析心理社会因素对HIV阳性者情绪障碍的影响,为开展心理干预提供依据。方法简单抽取感染HIV的既往病例250例,利用流调中心用抑郁量表（CES-D）、焦虑自评量表（SAS）、社会支持评定量表（SSS）、应对方式问卷、艾滋病认知评定量表（AQ）及艾滋病压力量表收集相关资料,对数据进行相关、回归分析。结果 HIV阳性者的抑郁、焦虑得分均值显著高于正常人群（P〈0.001）。AIDS相关压力分别解释抑郁、焦虑总变异的比例最大（54.1%、41.2%）,自责和解决问题均与两种情绪相关,威胁和客观支持仅与抑郁相关（P〈0.01）;此外,经济状况（月收入）也与焦虑有关。结论 HIV阳性者的抑郁、焦虑程度均显著高于正常人,可针对多种心理社会因素开展干预,促进阳性者的心理健康水平。     

An outbreak of influenza aboard a commercial airliner.

A jet airliner with 54 persons aboard was delayed on the ground for three hours because of engine failure during a takeoff attempt. Most passengers stayed on the airplane during the delay. Within 72 hours, 72 per cent of the passengers became ill with symptoms of cough, fever, fatigue, headache, sore throat and myalgia. One passenger, the apparent index case, was ill on the airplane, and the clinical attack rate among the others varied with the amount of time spent aboard. Virus antigenically similar to A/Texas/1/77(H3N2) was isolated from 8 of 31 passengers cultured, and 20 of 22 ill persons tested had serologic evidence of infection with this virus. The airplane ventilation system was inoperative during the delay and this may account for the high attack rate.     

Rubella screening and vaccination program for US Air Force trainees: an analysis of findings.

A preventive medicine program of rubella control for trainees at the Air Force Military Training Center, Lackland AFB, Texas, was begun in October 1977. Incoming trainees were screened for rubella susceptibility, and female trainees were additionally screened for pregnancy. During the period October 1977 to December 1978, an overall rubella susceptibility rate of 17.3 per cent was determined for 71,387 trainees entering basic training. Flights (50 persons each) to which these trainees are assigned varied widely in susceptibility from 0.0-47.7 per cent. Comparisons of susceptibility rates for trainees for for geographic areas and states indicated the highest overall percentage of susceptibles were from the Pacific geographic area with California showing the highest susceptibility (24.5 per cent). Race specific susceptibility rates were found to differ significantly between Whites and Blacks, 17.6 vs 14.8 per cent, respectively. The immunization program was effective as judged by a dampening of the incidence of clinical rubella at the basic training center and at other secondary training centers.     

Public access defibrillation: a shocking idea?

Currently, survival from out-of-hospital cardiac arrest in the United Kingdom is poor. Ambulance response standards require that an ambulance reach 75 per cent of cardiac arrests within 8 min. But a short time to defibrillation from the onset of collapse is a key predictor of outcome from out-of-hospital cardiac arrest. The Department of Health has recently implemented a lay responder defibrillation programme, with the aim of shortening this time interval for victims in public places. This initiative utilizes automated external defibrillators (AEDs), which provide written and recorded voice prompts to minimize training requirements and errors in use. Lay responder AED programmes with very short response times have reported survival to discharge rates of up to 53 per cent for patients presenting in ventricular fibrillation (VF). This compares well with the results of a meta-analysis that reported a survival rate of only 6.4 per cent for traditional defibrillator-equipped ambulance systems. The annual incidence of out-of-hospital cardiac arrest in England is 123 per 100,000 population. Approximately half of these present in VF, and could benefit from an AED programme. But only 16 per cent of cardiac arrests occur in a public place. It has been calculated that there are approximately 5,000 instances of VF in public places each year in England. If half of these patients can be reached and administered a first shock within 4 min of their collapse, an additional 400 victims may survive each year. Given the current investment by the DoH of 2 million pounds, this suggests a cost per life saved of approximately 505 pounds over a 10 year period.     

Childhood and adult trauma experiences of incarcerated persons and their relationship to adult behavioral health problems and treatment

Rates of childhood and adult trauma are high among incarcerated persons. In addition to criminality, childhood trauma is associated with the risk for emotional disorders (e.g., depression and anxiety) and co-morbid conditions such as alcohol and drug abuse and antisocial behaviors in adulthood. This paper develops rates of childhood and adult trauma and examines the impact of age-of-onset and type-specific trauma on emotional problems and behavior for a sample of incarcerated males (N~4,000). Prevalence estimates for types of trauma were constructed by age at time of trauma, race and types of behavioral health treatment received while incarcerated. HLM models were used to explore the association between childhood and adult trauma and depression, anxiety, substance use, interpersonal problems, and aggression problems (each model estimated separately and controlling for age, gender, race, time incarcerated, and index offense). Rates of physical, sexual, and emotional trauma were higher in childhood than adulthood and ranged from 44.7% (physical trauma in childhood) to 4.5% (sexual trauma in adulthood). Trauma exposure was found to be strongly associated with a wide range of behavioral problems and clinical symptoms. Given the sheer numbers of incarcerated men and the strength of these associations, targeted intervention is critical.