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Both in response to community concerns about brain cancer related to an oil refinery and in order to more fully understand the etiology of primary site brain cancer (glioma), a highly focused cancer cluster investigation was conducted. The components included: (1) a literature review of occupational exposures in the petroleum refining and petrochemical industries, (2) comparisons between observed and expected cases, (3) comparisons between mean age at diagnosis and median survival time and (4) interviews concerning exposures of cases. Evidence from the literature review revealed little, if any, effect of petroleum refinery or petrochemical exposure on the risk for brain cancer. There was no statistically significant increase in the number of brain cancer cases in the community (observed = 12, expected = 9.46, standardized mortality ratio = 1.27). There was no statistically significant decrease in mean age at diagnosis or median survival time among those most exposed. Reports of exposure from the case interviews were highest for eating processed meats (98.5%), dental X-rays (96.6%), dog ownership (91.2%) and swimming (80.3%). There were no major occupational exposures identified. It seems unlikely that petrochemicals are involved in any significant way in the etiology of most brain cancers (gliomas). A follow-up case-control study should focus primarily on those risk factors mentioned frequently by the cases., (Copyright 2003 S. Karger AG, Basel)

Influenza is an emerging and re-emerging disease. Since the late 1930s influenza viruses have been isolated yearly from different parts of the world during epidemics and pandemics. The "epidemiologic success" of influenza is due largely to rapid and unpredictable antigenic changes (antigenic drift) among human influenza viruses, and the emergence of new subtypes (antigenic shift), mostly from reassortment between human and avian influenza viruses. Antigenic shifts were attributed to the global pandemic viruses of 1957 (H2N2 Asian flu) and 1968 (H3N2 Hong Kong flu). Concern over possible new pandemics has been heightened by recent reports of human infection in Asia in 1997 with avian viruses (H5N1) and in 1999 (H9N2) and isolation of human-avian reassorted viruses from pigs and humans in Europe. Influenza has a high rate of inapparent infection, short incubation and high infectivity; epidemics usually start abruptly and spread rapidly to neighboring communities and countries. Isolation and quarantine are often unsuccessful in preventing the spread of the infection. Although not perfect, immunization and chemoprophylaxis are highly effective at minimizing the spread of influenza and reducing morbidity and mortality, social disruption and economic loss. Plans for future influenza epidemics and pandemics require national and international programs to be in place for the monitoring of influenza activity, the dissemination and exchange of information and the provision and delivery of sufficient quantities of vaccines and antiviral agents. This paper reviews and discusses the antigenic variations of the influenza virus, potential influenza pandemics, protective efficacy of inactivated vaccines and antiviral agents and preparation for control of future epidemics and pandemics.

Serratia marcescens bacteremia has become ubiquitous recently. S. marcescens bacteremia, either hospital- or community-acquired, can no longer be treated as insignificant. We reviewed 23 episodes of S. marcescens bacteremia in 1985. Among them, 17 patients (74%) were hospital-acquired infections, while 6 (26%) were community-acquired. Nine patients died, and the case fatality rate was 39%. Eleven patients (48%) had no clinically apparent source of infection, 5 (22%) had urinary tract infection, 3 (13%) had pneumonia, 2 (9%) had biliary tract infection, 1 (4%) had intra-abdominal infection, and 1 (4%) had skin and soft-tissue infection. Nosocomial isolates are often resistant to many antibiotics. Amikacin and the beta-lactamase-stable (third generation) cephalosporins are superior to gentamicin in the treatment of nosocomial S. marcescens bacteremia. We here emphasize that the awareness and treatment of S. marcescens bacteremia in daily clinical practice is unequivocally critical.

This investigation of a brain cancer cluster in Missouri used two approaches to investigate associations with potential risk factors. In a case-control study in a rural town, we interviewed surrogates of cases and controls about potential risk factors. We found a statistically significant positive association of brain cancer with reported exposure to dental X-rays. Occupation was not associated with the cluster in the rural town. In a standardized proportional mortality study for the state of Missouri, we calculated the observed and expected proportion of brain cancers by occupation and industry in Missouri decedents. We found that motor vehicle manufacturers, beauty shop workers, managers and administrators, elementary school teachers, and hairdressers and cosmetologists had significantly elevated proportions of brain cancer. Brain tumors are inconsistently associated with occupation in the literature. Further study of brain cancer etiology with respect to dental X-ray exposures seems warranted.

A cluster of seven primary brain neoplasms was identified in a town of 3000 population during the 10-year period from 1973 to 1982. With six deaths, this represents an age-adjusted mortality rate 4.1 times greater than expected. No other neoplasms were found to be in excess of the anticipated incidence in this town. When brain-tumor mortality rates in 36 other towns of approximately the same population were calculated, only one other town was found to have an excessive rate. All seven tumors in this study were histologically verified: six were diagnosed as glioblastoma multiforme. Interviews were conducted with patients or next-of-kin to obtain the exposure histories of the patients. A number of respondents reported occupational or residential exposure either to a shoe factory or to one of the several chicken hatcheries in the town. Many of the patients ate fish from local ponds that had previously been used as coal mining strip pits. Two patients were siblings. None of the patients had a history of significant head trauma. This unique situation may provide an opportunity to learn more about environmental risk factors for brain neoplasia. Further epidemiological studies are planned.

Ten years have now passed since the American Cancer Society/National Cancer Institute sponsored Breast Cancer Detection Demonstration Projects (BCDDP) started to evaluate the use of mammography, physical examination, thermography, and breast self-examination in screening women for the presence of unsuspected breast cancer. Criteria have been developed to evaluate population screening as an approach to cancer control and breast cancer screening techniques. Combined physical examination and mammography have been particularly successful in detecting early breast cancer. Although the number of screening programs for breast cancer has increased in the past decade, real progress has been surprisingly slow and the issues in breast cancer screening have proved to be subtle and complex.

A retrospective review of needlestick injuries was conducted for the period January 1979 through May 1981 at a major university teaching hospital. The objective of this review was to determine the needlestick injury rate among employees according to department, occupation, activity, shift, and full- or part-time status. Two hundred eighty-six incidents of needlestick injuries were recorded. Almost 90% of injuries occurred in nursing, housekeeping, and clinical laboratory personnel. Direct handling of needles primarily involved nursing and laboratory personnel. Housekeeping personnel were injured primarily as "innocent victims" hauling trash. Significantly elevated incidence rates were observed in part-time and night-shift personnel. Incidence rates in registered nurses significantly exceeded rates in licensed practical nurses. On the basis of these findings, it is suggested that prevention of such incidents should be focused on such high-risk groups.

There is evidence that fetal antigenic stimulation and intrauterine infection is much more frequent in developing rural populations than in industrialized societies. A similar contrast is observed for postnatal intestinal infection that is significantly greater in the less developed areas. The differences are explained by the divergence in environmental sanitation and personal hygiene. Intestinal infection is important in that diarrheal disease is one of the main factors leading to malnutrition. It is apparent that for developing nations to attain better nutrition, much of the present burden of intestinal infection needs to be controlled.

A laboratory based epidemiologic study was done to determine the possible relationship of herpesvirus type 2 to carcinoma of the prostate. A total of 305 patients (224 with benign prostatic hypertrophy and 81 with prostatic carcinoma) who underwent transurethral resection of the prostate was studied. Viral cultures were obtained from urethral swabs and urine preoperatively. Prostatic tissue removed at operation was grown as tissue explants, using a monolayer cell culture technique, and examined by specific immunofluorescence and electron microscopy for evidence of herpesvirus type 2. The sera of the patients also were tested for specific antibody to herpesvirus type 2 by the indirect hemagglutination inhibition test. Although herpesvirus was not isolated 5 per cent of the patients had evidence of herpesvirus type 2 antigen in prostatic tissues by specific immunofluorescence. Electron microscopy failed to reveal the presence of viral particles. There was an increased prevalence of herpesvirus type 2 antibody in patients with carcinoma of the prostate compared to the controls with benign prostatic hypertrophy (p less than 0.05). Although marital status was similar the patients with prostatic cancer tended to marry at an earlier age, have more children, more sexual partners and more exposure to prostitutes than their counterparts with benign prostatic hypertrophy. The demonstration of specific herpesvirus type 2 antibody in patients with prostatic cancer supports an etiologic role for herpesvirus type 2 but further studies are needed to describe more definitively the relationship since the indexes of sexual activity are remarkably high in both groups.

Using a mailed questionnaire, 185 U.S. and Canadian directors of medical school departments and residency programs were surveyed about the role of neuroepidemiology in clinical neurology. Data were obtained about current neuroepidemiologic staff; consultation patterns; current and future needs for neuroepidemiologists, including duties and level of training; funding of neuroepidemiologists; and training of residents and fellows. We recommend more centralized teaching of the epidemilogy of neurologic disease with participation by practicing neurologists, courses in neuroepidemiology in schools without special training programs, and improved training of residents and fellows, with more active participation by medical school epidemiologists.

The first proved outbreak of nosocomial Legionnaires' disease occurred in a psychiatric hospital in Washington D.C. in 1965, but the diagnosis was not established until determination of serum antibodies against Legionella pneumophila by the indirect fluorescent antibody (IFA) test was undertaken, using the bacterial antigen isolated from patients with Legionnaires' disease in the 1976 outbreak in Philadelphia. The second nosocomial outbreak of Legionnaires' disease occurred in three immunocompromised patients who received renal transplantation at the University of Kansas Medical Center and died of extensive lobar pneumonia in 1975. The direct fluorescent antibody (DFA) test revealed L. pneumophila in the lungs of all three patients after the Legionnaires' disease agent was identified. The lack of prospective surveys using sensitive diagnostic procedures by various types has limited our knowledge on the extent of the problem caused by legionella. In fact, nosocomial Legionnaires' disease is a worldwide problem, and control of this disease requires thorough cooperation of physicians, epidemiologists, microbiologists and expert engineers.

Epidemiologic studies suggest that high levels of immunity induced by inactivated poliovirus vaccine could limit the spread of poliomyelitis in the community. Antibody induced by this vaccine had a marked effect on reducing pharyngeal virus excretion in children with poliovirus infection. Some reduction of fecal virus excretion was also observed, but high levels of serum antibody were required for this reduction.

Among 223 volunteer blood donors who were studied for evidence of cytomegalovirus (CMV) infection, 58 percent had complement-fixing antibody and 59 percent had indirect hemagglutinating antibody to CMV. No virus was isolated from any donor's washed leukocytes or leukocyte-rich plasma in fibroblast monolayer culture. In seven asymptomatic donors (3 percent), CMV was recovered from urine cultures obtained at the time of blood donation. However, at the time of reexamination, viruria was no longer present and serum antibody titers had not changed. In the three patients studied who received blood from three of the cytomegaloviruric donors, serological evidence of CMV infection developed (fourfold or greater indirect hemagglutinating antibody rise), and one recipient also developed cytomegaloviruria; no illnesses was associated with these infections. Further study is needed to establish that the detection of viruria in donors may identify potentially infective blood.

Retrospective study shows that a 1957 outbreak of pneumonia in Austin, Minnesota, was Legionnaires' disease. Between June 7 and August 9, 1957, 78 persons were hospitalized with acute respiratory disease of unknown cause. Most had fever, headache, cough, and pneumonitis; two died. Ages ranged from 14-83 years; half of the patients were aged 55 years or older. Eighty-seven per cent were men. There were no secondary cases. Forty-six (59%) of the 78 patients were employees at a local meat packing plant, in distinction to the area's total working population (32%). Serosurvey of 15 of the 1957 outbreak cases and 30 controls matched for age, sex, and either occupation or residence was carried out in 1979. Antibody titers were determined for Legionella pneumophila serogroups 1-4 by means of indirect immunofluorescence. Twelve (80%) of the 15 cases and 13 (43%) of the 30 controls had antibody titers of 1:64 or greater to one or more of the L. pneumophila serogroups. Significant differences in L. pneumophila antibody titers (prevalence and level) were found between cases and control groups matched for residence (serogroups 1-3) or occupation (serogroups 2 and 3). Only three of 20 Austin residents with pneumonia diagnosed between 1978 and 1980 had L. pneumophila antibody titers of 1:128 or greater (p less than 0.001), in comparison to cases. These serologic data and the 1957 clinical and epidemiologic observations support the contention that this is the earliest documented outbreak of Legionnaires' disease.

Over 1,200 white mothers who were delivered consecutively at this medical center were classified in four different socioeconomic classes according to family affluence and occupations of the heat of the household. The frequency of low-birth-weight infants was highest in the lowest socioeconomic class. The high incidence of LBW infants in the lowest socioeconiomic group was not affected by any significant increase in number of mothers with medical problems or medical complications of pregnancy; it was dependent on the large number of mothers who were involved in four specific practices, largely of their own choosing, including low-weight gains, cigarette smoking, use of certain drugs during pregnancy, and refraining from all prenatal care. Mothers in the four socioeconomic classes who were not involved with these four specific practices (smoking, etc.) and whose pregnancies were free of medical problems and complications had uniformly low incidences of LBW infants and the mean birth weights of their infants were uniformly high and not significantly different. Unfavorable outcome of pregnancy with respect to fetal growth in this study appeared to depend less directly on socioeconomic circumstances than on the four specific maternal practices listed above.

A method for determination of serum-neutralizing antibody titers to rhinovirus type 16 and coxsackievirus type A-4 in human diploid cells (WI-38) grown in Microtiter plates is described. A good correlation was observed when comparing neutralization tests in WI-38 and other cells. The WI-38 Microtiter method is relatively simple and economical. It is suitable for those laboratories which are required to conduct large-scale serological evaluation of antibodies for rhinoviruses and coxsackie A viruses. This system also can be used for cytomegalovirus and varicella-zoster virus, which grow relatively slowly.