The role of seafood in foodborne diseases in the United States of America

In the United States of America, seafood ranked third on the list of products which caused foodborne disease between 1983 and 1992. Outbreaks connected with fish vectors were caused by scombroid, ciguatoxin, bacteria and unknown agents; in shellfish, unknown agents, paralytic shellfish poisoning, Vibrio spp. and other bacteria, followed by hepatitis A virus, were responsible for the outbreaks. At least ten genera of bacterial pathogens have been implicated in seafood-borne diseases. Over the past twenty-five years, bacterial pathogens associated with faecal contamination have represented only 4% of the shellfish-associated outbreaks, while naturally-occurring bacteria accounted for 20% of shellfish-related illnesses and 99% of the deaths. Most of these indigenous bacteria fall into the family Vibrionaceae which includes the genera Vibrio, Aeromonas and Plesiomonas. In general, Vibrio spp. are not associated with faecal contamination and therefore faecal indicators do not correlate with the presence of Vibrio. Viruses are the most significant cause of shellfish-associated disease: in New York State, for example, 33% and 62% of 196 outbreaks between 1981 and 1992 were caused by Norwalk virus and gastrointestinal viruses (small round structured viruses), respectively. In addition, several illnesses are a result of toxic algal blooms, the growth of naturally occurring bacteria and diatoms causing neurotoxic shellfish poisoning, paralytic shellfish poisoning, diarrhoetic shellfish poisoning, amnesic shellfish poisoning and ciguatera. Current estimates place the annual number of ciguatera cases at 20,000 world-wide. Scombroid poisoning is the most significant cause of illness associated with seafood. Scombrotoxin is of bacterial origin and halophilic Vibrio spp. causing high histamine levels are implicated as the source. Scombroid poisoning is geographically diverse and many species have been implicated, namely: tuna, mahi-mahi, bluefish, sardines, mackerel, amberjack and abalone. Temperature abuse has been cited as a major cause of scombroid poisoning. For routine work, the use of faecal indicators to predict the relative level of faecal contamination should not be disposed of. However, the main source of seafood illness is due to species which are not predicted by these organisms. In order to protect public health, routine surveillance using new pathogen-specific techniques such as polymerase chain reaction should be used. This, in combination with risk assessment methods and hazard analysis and critical control points, will begin to address the need for improvement in the safety of seafood.     

Traumatic occupational fatalities in the retail industry, United States 1992-1996

BACKGROUND: Retail is a growing economic sector and employs an increasing number of the overall workforce, yet little is known about the incidence and characteristics of work-related deaths in the retail industry. METHODS: Workplace deaths were examined using the Census of Fatal Occupational Injuries from 1992 through 1996. Occupational fatality rates were calculated by age, gender, and type of establishment, and characteristics of occupational deaths in the retail industry were compared to other industries. RESULTS: Liquor stores had the highest work-related fatality rates in the retail industry. The two leading causes of death in the retail industry were violence (69.5%) and motor vehicle crashes (19.3%). Females, younger, minority, and foreign-born workers were more likely to be killed in retail than other industries. Deaths in the retail industry were more likely to be in small businesses, after normal business hours, and in urban settings. DISCUSSION: Workers in the retail industry were at lower risk of most types of workplace deaths but had a markedly increased risk of violent death than workers in other industries.     

Changing epidemiology of congenital rubella syndrome in the United States

To describe clinical presentation and epidemiology of US infants with congenital rubella syndrome (CRS) and to identify missed opportunities for maternal vaccination, data from CRS cases reported to the National Congenital Rubella Syndrome Registry (NCRSR) from 1985 through 1996 were analyzed. Missed opportunities for maternal vaccination were defined as missed postpartum, premarital, and occupational opportunities, that is, times when rubella vaccination is recommended but was not given. From 1985 through 1996, 122 CRS cases were reported to the NCRSR. The most frequent CRS-related defect was congenital heart disease. Of the reported infants with CRS, 44% were Hispanic. Of 121 known missed opportunities for rubella vaccination among 94 mothers of infants with indigenous CRS, 98 (81%) were missed postpartum opportunities. CRS continues to occur in the United States. Hispanic infants have an increased risk of CRS. Missed opportunities for postpartum rubella vaccination were identified for 52% of indigenous CRS cases.     

Radionuclides in domestic and imported foods in the United States, 1987-1992

Findings from the U.S. Food and Drug Administration's Radionuclides in Foods program are summarized for foods collected between October 1, 1986, and September 30, 1992. Concentrations of radionuclide activity in the Total Diet Study and reactor-survey foods were in Range 1 or low in Range II of the surveillance and control recommendations of the Federal Radiation Council; no control actions were suggested. Dietary intake of 90Sr continued the general decline observed since 1961. Approximately 2600 test portions of imported foods were analyzed for contamination associated with the Chernobyl nuclear accident. Concentrations of radionuclide activity were below limits of detection for the vast majority of the imported food test portions but were above the levels of concern for 23 portions. Since 1986, the fraction of imported food test portions having measurable amounts of contamination has steadily declined, as have the average concentrations of radionuclide activity; however, contamination is still occasionally found. Continued monitoring of both domestic and imported foods is planned.     

Respiratory diphtheria in the United States, 1980 through 1995

OBJECTIVES: The purpose of this study was to describe the epidemiologic, laboratory, and clinical features of respiratory diphtheria cases reported in the United States during 1980 through 1995. METHODS: Respiratory diphtheria cases reported to the Centers for Disease Control and Prevention were reviewed. Cases were defined as physician-diagnosed cases with signs and symptoms compatible with respiratory diphtheria, including the presence of a pseudomembrane without other apparent cause. RESULTS: From 1980 through 1994, 41 respiratory diphtheria cases were reported; none were reported in 1995, and no secondary cases were identified. Nine (22%) case patients were 4 years of age or younger, and 28 (68%) were 15 years of age or older. None of the case patients were up to date with diphtheria vaccination; 4 unvaccinated children died. Seventeen (43%) of 40 case patients had positive culture results. CONCLUSIONS: Available surveillance data suggest that respiratory diphtheria has become a rare disease in the United States. However, importation and circulation of toxigenic strains continue to present a threat and require achieving and maintaining high coverage with diphtheria toxoid-containing vaccines in both children and adults.     

Relationship of internal-external control and United States suicide rates, 1966-1973

The annual variations in scores obtained on the Rotter Internal-External (I-E) control scale by United States college students between the years 1966 and 1973 were related to the concomitant annual variations in suicide rates for the total United States population and for eight separate age groups. The I-E scores increased substantially during this time period and were correlated positively with the concomitantly increasing suicide rates among relatively young persons (in and below the 35-44 year age group). However, the suicide rates among older persons generally decreased during this time period and thus were correlated negatively with the I-E scores. These results suggest that perception of internal-external control did not change among older persons as they did among younger persons, perhaps because older persons might be less susceptible to the cultural influences that affect the perceived control of younger persons. Results of this and earlier research suggest that cultural characteristics that foster high perceptions of external control also foster suicidal behavior and suggest the value of attempts to convey perceptions of internal control to psychotherapy clients.     

The fall after the rise: Tuberculosis in the United States, 1991 through 1994

A thrombin-like enzyme, balterobin, was purified from the venom of Bothrops alternatus. The purification steps included Sephadex G-75, heparin-sepharose and reverse phase HPLC C-18 column. Balterobin showed an apparent molecular weight of 30,000 in non-reduced conditions and displays a specific coagulant activity of 32.8 NIH units/mg over bovine fibrinogen. It also exhibits arginine amidase activity on DL-BAPNA. Like thrombin-like enzymes from other snakes, balterobin possesses valine as N-terminal residue, and is inhibited by PMSF.     

Abortion training in obstetrics and gynecology residency programs in the United States, 1991-1992

According to a 1991-1992 survey of program directors of obstetrics and gynecology residency programs in the United States, the overall percentage of programs providing any training in first-trimester (70%) or second-trimester abortion (66%) has changed very little since 1985. However, the proportion of programs providing routine training in first-trimester abortion decreased from 23% in 1985 to 12% in 1991-1992, and the proportion providing routine training in second-trimester abortion declined from 21% to 7%. The majority of the programs that dropped routine abortion training continued to offer optional training, but residents in programs with optional training were less likely to receive training. More than 80% of programs in private, non-Catholic hospitals and public hospitals provided some form of abortion training in 1991-1992, but only 6% of programs in Catholic hospitals and no military programs did so. In 45% of programs offering abortion training, residents performed one or fewer abortions per week.     

The epidemiology of genitourinary fistulae in Kumasi, Ghana, 1977-1992

The aim of the study was to determine the clinical epidemiology of genitourinary fistulae as seen at Komfo Anokye Teaching Hospital in Kumasi, Ghana. A retrospective study was carried out from the hospital records and operative reports of all patients with genitourinary fistulae seen at Komfo Anokye Teaching Hospital between January 1977 and December 1992. Patient age, parity, type of fistula and cause of fistula were abstracted from the medical records. There were 164 cases of genitourinary fistula managed during the study period. There were 150 fistulae due to obstetric causes (91, 5%), the vast majority of which were due to prolonged obstructed labor (121 cases, 73.8% of all fistulae), with a minority related to complications of lower-segment cesarean section (14 cases, 8.5% of all fistulae). In 5 cases (3.1%) patients developed a rectovaginal fistula owing to perineal tears and prolonged obstructed labor. During this time period there were 157,449 deliveries, giving an obstetric fistula rate of 1 fistula per 1000 deliveries. Obstetric fistulae were most common at the extremes of reproductive age and parity Fourteen additional fistulae (8.5% of all cases) were due to gynecologic causes, most commonly from surgical injury occurring at the time of abdominal hysterectomy for leiomyomata uteri (12 cases, 7.3% of all fistulae). It was concluded that in Kumasi, Ghana, obstetric trauma from prolonged obstructed labor is the most common cause of genitourinary fistula formation. Such fistulae occur in older multiparous women as well in young primigravidae. Obstructed labour can, and does, occur in women who have previously undergone uneventful vaginal delivery. Birth attendants should be aware of that fact. Prompt referral for obstetric intervention should be made in obstructed labor, irrespective of the age and parity of the patient.     

Prevalence of multiple cardiovascular disease risk factors among women in the United States, 1992 and 1995: the Behavioral Risk Factor Surveillance System

We sought to examine the prevalence of self-reported multiple cardiovascular disease (CVD) risk factors (hypertension, high blood cholesterol, diabetes, overweight, and current smoking) among women in 1992 and 1995 in the United States using data from the Behavioral Risk Factor Surveillance System. In 1992, 37.5%, 34.4%, and 28.1% of women had zero, one, and two or more of the five risk factors, respectively. In 1995, the respective estimates were 35.5%, 34.3%, and 30%. In both years, the prevalence of two or more risk factors increased with age, decreased with educational level, was higher among black women (lowest among Hispanic women and women of other ethnic groups), and higher among women reporting cost as a barrier to healthcare. The percentage of women with two or more risk factors was higher in 1995 than in 1992 for 35 of 48 states, being statistically significant for 7 states. The percentage of women with at least two risk factors was not significantly lower in 1995 than in 1992 for any state. A higher percentage of women reported having multiple CVD risk factors in 1995 compared with 1992. A multifactorial approach to primary prevention and risk factor reduction should be encouraged to help reduce the prevalence and burden of CVD among women.     

Trends in reported incidence of primary malignant brain tumors in children in the United States

BACKGROUND: The reported incidence of primary malignant brain tumors among children in the United States increased by 35% during the period from 1973 through 1994. The purpose of our study was twofold: 1) to determine whether the reported incidence rates for this period are better represented by a linear increase over the entire period ("linear model") or, alternatively, by a step function, with a lower rate in the years preceding 1984-1985 and a constant higher rate afterward ("jump model"); and 2) to identify the specific brain regions and histologic subtypes that have increased in incidence. METHODS: Incidence data from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute for the period from 1973 through 1994 for primary malignant brain tumors in children were used to model the number of cases in a year as a random variable from a Poisson distribution by use of either a linear model or a jump model. RESULTS/CONCLUSIONS: The increase in reported incidence of childhood primary malignant brain tumors is best explained by the jump model, with a step increase in incidence occurring in the mid-1980s. The brain stem and the cerebrum are the primary sites for which an increase in tumor incidence has been reported. The increase in reported incidence of low-grade gliomas in the cerebrum and the brain stem (unaccompanied by an increase in mortality for these sites) supports the substantial contribution of low-grade gliomas to the overall increase in reported incidence for childhood brain tumors. IMPLICATIONS: The significantly better fit of the data to a jump model supports the hypothesis that the observed increase in incidence somehow resulted from changes in detection and/or reporting of childhood primary malignant brain tumors during the mid-1980s.     

Agents, vehicles, and causal inference in bacterial foodborne disease outbreaks: 82 reports (1986-1995)

OBJECTIVE: To examine the study design of, and the practice of causal inference in, investigations of bacterial foodborne disease outbreaks occurring in the United States and to summarize agents and vehicles identified. DESIGN: Retrospective study. PROCEDURE: An online medical reference database was searched for reports of bacterial foodborne disease outbreak investigations published between 1986 and 1995. Reports were retrieved and reviewed for use of 9 causal criteria in investigations. Information on etiologic agents, vehicles, seasonality, and primary study design from each outbreak was also retrieved. RESULTS: 82 reports were retrieved and reviewed. Coherence, consistency, temporality, and strength of association were the causal criteria most commonly used in foodborne disease outbreak investigations. Coherence was used in all investigations. The number of criteria used ranged from 3 to 7. Meat (n = 20) and eggs (12) were the most commonly implicated vehicles. Salmonella sp and Escherichia coli O157:H7 accounted for 55% of agents reportedly isolated. Cohort and case-control methods were the most common study designs. CLINICAL RELEVANCE: Patterns were found in the use of causal criteria in foodborne disease outbreak investigations. These criteria can provide veterinarians and other public health practitioners with a means to effectively conceptualize, communicate, and summarize causal conclusions. The 4 most commonly used criteria may represent core criteria that investigators consider most useful in explaining food-borne disease outbreaks.     

Income dynamics and adult mortality in the United States, 1972 through 1989

OBJECTIVES: The aim of this study was to examine relationships between income and mortality, focusing on the predictive utility of single-year and multiyear measures of income, the shape of the income gradient in mortality, trends in this gradient over time, the impact of income change on mortality, and the joint effects of income and age, race, and sex on mortality risk. METHODS: Data were taken from the Panel Study of Income Dynamics for the years 1968 through 1989. Fourteen 10-year panels were constructed in which predictors were measured over the first 5 years and vital status over the subsequent 5 years. The panels were pooled and logistic regression was used in the analysis. RESULTS: Income level was a strong predictor of mortality, especially for persons under the age of 65 years. Persistent low income was particularly consequential for mortality. Income instability was also important among middle-income individuals. Single-year and multiyear income measures had comparable predictive power. All effects persisted after adjustment for education and initial health status. CONCLUSIONS: The issues of low income and income instability should be addressed in population health policy.     

Clinical features of moyamoya disease in the United States

BACKGROUND AND PURPOSE: We report the clinical features and longitudinal outcome of the largest cohort of patients with moyamoya disease described from a single institution in the western hemisphere. Moyamoya disease in Asia usually presents with ischemic stroke in children and intracranial hemorrhage in adults. METHODS: Our study population included all patients with moyamoya disease evaluated at a university hospital in Houston, Texas from 1985 through 1995 (n = 35). We used Kaplan-Meier methods to estimate individual and hemispheric stroke risk by treatment status (medical versus surgical). Predictors of neurological outcome were assessed. RESULTS: The ethnic background of our patients was representative of the general population in Texas. The mean age at diagnosis was 32 years (range, 6 to 59 years). Ischemic stroke or transient ischemic attack was the predominant initial symptom in both adults and children. Of the 6 patients with intracranial hemorrhage, 5 had an intraventricular site of hemorrhage. The crude stroke recurrence rate was 10.3% per year in 116 patient-years of follow-up. Twenty patients underwent surgical revascularization, the most common procedure being encephaloduroarteriosynangiosis. The 5-year risk of ipsilateral stroke after synangiosis was 15%, compared with 20% for medical treatment and 22% overall for surgery. CONCLUSIONS: Our observations indicate that moyamoya disease may have a different clinical expression in the United States than in Asia, and may demonstrate a trend toward a lower stroke recurrence rate and better functional outcome after synangiosis.     

Trends in infectious disease hospitalizations in the United States, 1980-1994

BACKGROUND: A recent study concluded that between 1980 and 1992, deaths from infectious diseases increased 58%. This article explores trends in infectious diseases as a cause of hospitalization. METHODS: We analyzed data from the National Hospitalization Discharge Survey for 1980 through 1994 using a previously developed approach to evaluate infectious diseases in data coded according to the International Classification of Diseases, Ninth Revision. RESULTS: Between 1980 and 1994, the rate of hospitalizations in the United States declined approximately 33%; hospitalizations occurred at a rate of 133+/-5 per 1000 US population (35 million+/-1 million discharges) in 1994. The rate of hospitalization for infectious diseases declined less steeply--12% during this interval--resulting in an increased proportion of hospitalizations because of infectious diseases. In 1994, the rate of hospitalizations for infectious diseases was 15.4+/-0.7 per 1000 US population (4.0 million+/-0.2 million discharges). The fatality rate associated with hospitalizations for infectious diseases increased from 1.9%+/-0.1% to 4.0%+/-0.3%, attributable to increased hospitalizations of elderly persons and an increased fatality rate among those younger than 65 years. Among selected categories, hospitalizations for human immunodeficiency virus infections and acquired immunodeficiency syndrome, prosthetic device infections, sepsis, and mycosis increased substantially, and hospitalizations for upper respiratory tract infections, pelvic inflammatory disease, and oral infections declined sharply. Hospitalizations for lower respiratory tract infections constituted 37% of all infectious disease hospitalizations in 1994. CONCLUSIONS: Considering hospitalizations as a dimension of the burden of infectious diseases involves an array of factors: secular trends in hospitalization, changing case management practices, demographic changes, and trends in the variety of infectious diseases themselves. Increases in the proportions of hospitalizations because of infectious diseases during years when hospitalizations for all causes were decreasing reflect an increasing burden of infectious diseases in the United States between 1989 and the mid-1990s.