Donnell P. Ewert

An Outbreak of Acute Gastroenteritis Caused by a Small Round Structured Virus in a Geriatric Convalescent Facility

An outbreak of acute gastroenteritis (AGE) occurred in a 201-bed geriatric convalescent facility in Los Angeles County during December 1988 through January 1989. The attack rate was 55% among residents and 25% among employees. Illnesses were characterized by vomiting and diarrhea to a lesser extent, and the absence of fever. Bacterial and parasitic tests in a sample of patients were negative. A 27 nm small round structured virus (SRSV) was identified in one of 30 stools studied by immune electron microscopy (IEM). While rotavirus and influenza A and B were found in three, one and three cases, respectively, no alternative etiologic agent could be demonstrated for most cases. The outbreak met Centers for Disease Control (CDC) clinical and epidemiologic criteria for Norwalk-like gastroenteritis. The death rate of residents was not elevated beyond baseline during the outbreak; however, one healthy employee had diarrhea and dehydration and died after developing an arrhythmia. An autopsy showed moderate, diffuse lymphocytic and neutrophilic myocarditis, and viral studies found influenza A in left ventricular tissue. Fourteen (25%) of 57 employee cases worked in occupations without routine stool or patient contact. At least nine of these employees lacked evidence of direct fecal contact, and transmission of infection in these cases may have been airborne.

Listeria monocytogenes infection and serotype distribution among HIV-infected persons in Los Angeles County, 1985-1992.

Persons infected with human immunodeficiency virus (HIV) are at greater risk of infection with Listeria monocytogenes (LM) than the general population. We quantify the risk of listeriosis in persons with acquired immune deficiency syndrome (AIDS) and HIV infection in Los Angeles County (LAC) and report the LM serotype distribution among HIV-infected patients with listeriosis. Active surveillance for listeriosis was performed in LAC during most of the period from 1985 through 1992. Thirty-four (10%) of 351 nonperinatal cases of listeriosis reported in LAC from 1985 through 1992 were in HIV-infected persons, 25 of whom met the 1987 AIDS case definition. The incidence of listeriosis was 95.8 and 8.8 cases per 100,000 person-years among persons with AIDS and all HIV-infected persons, respectively, but only 1.0 case per 100,000 person-years in the total population. Excluding cases from a 1985 listeriosis epidemic associated with consumption of contaminated Mexican-style cheese, 11 (65%) of 17 HIV-infected persons with available isolates were infected with LM serotype 1/2b, whereas only 64 (31%) of 208 other persons with listeriosis and available isolates were infected with LM serotype 1/2b (odds ratio = 4.1; 95% confidence interval = 1.3-14.1). LM serogroup 1/2b may have been more common among HIV-infected persons in LAC than among other persons with listeriosis because of differences in diet or sexual practices, or to chance alone. Persons with HIV-infection, especially those with AIDS, should be educated in avoiding foods at high risk of listerial contamination, such as soft cheeses, foods sold from delicatessen counters, and undercooked chicken.

A cluster of coagulase-negative staphylococcal bacteremias associated with peripheral vascular catheter colonization in a neonatal intensive care unit

BACKGROUND A cluster of six neonatal cases of coagulase-negative staphylococcal bacteremias occurred in a Los Angeles County neonatal intensive care unit in March 1989. METHODS A retrospective cohort study assessed the impact of host-and delivery-related variables, length of hospitalization, duration of antibiotic treatment, performance or duration of invasive procedures, and staffing variables on risk of coagulase-negative staphylococcal bacteremia. RESULTS Unstratified analyses yielded eight risk factors with risk ratios greater than 2. After stratification by gestational age (less than 29 weeks) and low birth weight (less than 1500 gm), frequency of blood transfusions, duration of respiratory therapy, heparin lock and central vascular line placement, and hyperalimentation remained associated with elevated risk. Two species were identified, arguing against a common source of infection. Of four cohort months with more than 15 very low birth weight infants in the neonatal intensive care unit, an elevation of coagulase-negative staphylococcus-positive blood cultures and diagnosed bacteremias occurred in only two. CONCLUSIONS This cluster of coagulase-negative staphylococcal bacteremia was probably caused by frequent manipulation of catheters in neonates who were at heightened risk because of low birth weight and prematurity.

A survey of hospital postpartum and postabortion rubella vaccination policies in Los Angeles County, 1992.

OBJECTIVE To determine the proportion of Los Angeles County (LAC) hospitals offering obstetrical services that have postpartum and postabortion rubella vaccination policies. DESIGN A survey was sent to the infection control practitioners (ICPs) of all operational acute care hospitals (N = 133) in LAC in 1992. A remainder and second survey was mailed to ICPs who did not respond to the first mailing. RESULTS Of 75 hospitals with obstetrical departments, 56 (75%) responded. Thirty-four (61%) of the 56 respondent hospitals had post-partum rubella vaccination policies. Of the 34 hospitals with policies, 30 (88%) accepted only a written record of rubella seropositivity as proof of immunity, 30 (88%) screened women with unknown immunity status before hospital discharge, and 32 (94%) vaccinated susceptible women before hospital discharge. Of the 32 hospitals that performed induced abortions, only two (6%) provided screening and vaccination services for these women. CONCLUSION Only 61% of hospitals in LAC offering obstetrical services had postpartum rubella vaccination policies while only minimal screening and vaccination occurred in association with abortion services. Widespread implementation of postabortion screening and vaccination, and more stringent compliance with Advisory Committee on Immunization Practices recommendations for postpartum screening and vaccination in hospitals offering obstetrical services would reduce the number of rubella-susceptible women who have been missed by other prevention strategies.

A comparison of hospital policies for measles, mumps, and rubella infection control in Los Angeles County, 1989 and 1992

BACKGROUND A survey was conducted in 1992 in Los Angeles County, California, to assess changes since an earlier survey in 1989 in the numbers of acute care hospitals that had established policies on measles, mumps, and rubella infection control and the extent to which these policies were implemented. METHODS A questionnaire inquiring about measles, mumps, and rubella infection control was sent to ICPs of 133 acute care hospitals in Los Angeles County. The results were compared with those of a similar survey conducted in 1989. The increase in the number of hospitals with such policies between 1989 and 1992 was analyzed. RESULTS In 1989, 29 (28%), 9 (9%), and 65 (64%) of the 102 respondent hospitals had measles, mumps, and rubella infection control policies, respectively. Larger proportions of the 95 respondent hospitals in 1992 had measles (56, 59%), mumps (15, 16%), and rubella (69, 73%) infection control policies. CONCLUSIONS The number of hospitals with infection control policies for measles, mumps, and rubella increased from 1989 to 1992. Efficiency and scope of such policies varied, however, and could be improved by making the policies mandatory, requiring written documentation of employee immunity, and extending policies to cover all employees. The most dramatic increase was in the number of hospitals with infection control policies for measles; this increase may have been caused by the 1987 to 1989 measles epidemic in Los Angeles County, by increased awareness of the Immunization Practices Advisory Committee recommendations, or by increased sensitivity to the issue of infection control triggered by the 1989 survey.

Resurgence of Congenital Rubella Syndrome in the 1990s: Report on Missed Opportunities and Failed Prevention Policies Among Women of Childbearing Age

OBJECTIVE To assess previous missed opportunities for rubella screening and vaccination of women delivering infants with congenital rubella syndrome and to discuss prevention strategies. DESIGN Descriptive analysis of data collected through interviews and review of medical records. POPULATION STUDIED Twenty-one women who delivered infants with congenital rubella syndrome in four Southern California counties from January 1, 1990, through January 8, 1991. RESULTS Twelve (57%) of the women had a total of 22 known missed opportunities for rubella screening or vaccination. Of the 22 missed opportunities, three (14%) were missed screenings at the time of marriage, two (9%) were missed screenings during previous pregnancies, five (23%) were missed screenings during induced abortions, and 12 (55%) were missed opportunities for vaccination postpartum or after induced abortions. Nine (43%) of the women had no known missed opportunities for rubella screening or vaccination. Of 12 women educated in California, only four (33%) were subject to the 1982 California school rubella immunization requirement. CONCLUSIONS Congenital rubella syndrome could have been prevented in more than half of the infants born to these women if missed opportunities for rubella testing and/or vaccination had not occurred. Because premarital rubella testing and school immunization requirements do not ensure that all women of childbearing age are immune to rubella, physicians and hospitals should establish procedures for postpartum rubella vaccination of susceptible women. Family planning and abortion clinics should implement routine rubella testing and follow-up vaccination of susceptible women.

Resurgence of congenital rubella syndrome in the 1990s: Report on missed opportunities and failed prevention policies among women of childbearing age

defects. Thirty-nine patients were at high risk and 30 patients were at low risk for cardiac anomalies. All fetuses were scanned with standard four-chamber and outflow tract views. Data concerning extracardiac anomalies and karyotypic abnormalities were tabulated. The accuracy of the four-chamber view alone in identifying congenital heart defects was evaluated. Results: Fifty-seven of 69 fetuses (83%) were prenatally identified uhrasonographically as having a heart defect. There was no difference in the sensitivity of detecting cardiac anomalies between high-risk and low-risk groups. When the four-chamber view was used, only 63% of fetuses were recognized as having an abnormal heart. Extracardiac anomalies were noted in 36% and karyotypic abnormalities in 17% of patients. Conclusion: The four-chamber and outflow tract views done routinely in an uhrasonography laboratory seeing a mixed population of patients was successful in detecting 83% of fetuses with structural cardiac malformations. Because 43% of the fetuses with heart defects were referred for low-risk indications, systematic ultrasonographic examination of the fetal heart should not be reserved only for those at high risk.