A cluster of sternal wound infections requiring muscle flap repair: problems in epidemiologic investigation.

A cluster of sternal wound infections (SWI) requiring muscle flap closure occurred in a California hospital in 1988. Review of SWI rates by surgical team revealed that a single team (Team A) was associated with a cluster of SWI requiring muscle flap repair (MFR). Team A's rate of SWI requiring MFR was 2.27% in 441 heart operations. A case/control study was conducted to determine if the higher rate of SWI requiring MFR could be attributed to disproportionately large numbers of patients at high risk treated by Team A. Data on major risk factors for SWI collected for case and control groups included the following: age at operation, weight, body surface area, history of obesity, diabetes mellitus, or cigarette smoking, duration of cardiopulmonary bypass, use of internal mammary artery graft, number of coronary arteries bypassed, use of prostheses, operating room staffing, and emergent nature of operation. No statistically significant differences between Team A cases requiring MFR and control cases were observed for predisposing risk factors. Surgical technique remains a principal suspected risk factor for SWI requiring MFR in this cluster.

HIV seroprevalence in intravenous drug users: Los Angeles, California, 1986.

To estimate the seroprevalence and investigate risk behaviors for HIV (human immunodeficiency virus) infection in intravenous drug users in Los Angeles County, a stratified, random sample of 790 clients, enrolled in either methadone maintenance or detoxification programs, were studied. Thirteen study participants (1.8 per cent) were seropositive; of these, five were homosexual/bisexual males and three were female prostitutes. Ninety-five per cent of all participants reported sharing needles. Risk reduction education efforts must be expanded before the HIV antibody prevalence rate increases.

Improving disease reporting in Los Angeles County: trial and results.

A telephone survey of physicians in Los Angeles County revealed that 50 percent of 405 contacted were unaware of the legal mechanism for reporting communicable diseases--the Confidential Morbidity Report (CMR) card. After that survey, three measures were taken in an effort to improve reporting and surveillance: (a) use of a stamped self-addressed CMR postcard, (b) publication of the monthly newsletter "Public Health Letter," which was distributed to 23,000 health professionals in Los Angeles County free of charge, and (c) initiation of an active disease surveillance system that included 171 reporting sites contacted weekly (76 physicians, 36 schools, 33 preschools, 22 hospitals, and 4 university student health centers). No increase in the levels of disease reporting was observed, based on 4 years' experience with the revised CMR card and the Public Health Letter. The active disease surveillance system, however, has provided anecdotal reports of disease occurrence and notification of outbreaks of both reportable and nonreportable diseases. Moreover, the authors believe it has improved rapport between the county health department and the medical community.

Public health at the 1984 Summer Olympics: the Los Angeles County experience.

During the 1984 Summer Olympic Games, the Los Angeles County Department of Health Services used its active disease surveillance system to monitor disease occurrence and other health concerns. Reports were collected by telephone three times a week from 198 participating facilities including hospitals, prepaid health plans, private physicians, and Olympic sites. Background data were obtained two months preceding the Olympic events. Less illness was recorded during the Olympics than during the same period for the three preceding years.

Listeriosis: an uncommon opportunistic infection in patients with acquired immunodeficiency syndrome. A report of five cases and a review of the literature.

Between January 1985 and March 1986, five cases of listeriosis were reported in Los Angeles County in patients with the acquired immunodeficiency syndrome (AIDS). All patients were homosexual men with no other risk factors for AIDS. Two patients had sepsis only, two patients had sepsis and meningitis, and one patient had sepsis and signs of meningitis. Sixty percent of the cases (three patients) had a prior or concurrent gastrointestinal illness. Eighty percent of the cases (four patients) also had no prior history of antibiotic administration. Both of these findings may have predisposed these AIDS patients to be at increased risk for listeriosis. Although listeriosis is an infrequent illness in AIDS patients, people with AIDS or human immunodeficiency virus infection should probably refrain from ingesting food items associated with listeriosis. These food items include improperly pasteurized dairy products, and raw fruits and vegetables not properly washed.

An outbreak of respiratory syncytial virus pneumonia in a nursing home for the elderly.

An outbreak of pneumonia and febrile respiratory illness took place in a Los Angeles County nursing home for the elderly in February and March of 1979. Forty of 101 (40%) residents were affected. Twenty-two (55%) had pneumonia and eight (20%) died. The outbreak extended over a period of 6 weeks. Serological evidence implicated respiratory syncytial virus (RSV) as the causative agent. Three patients had fourfold or greater rises in the titre of antibody to RSV, one had high titres in paired samples of serum, while nine had a titre of greater than or equal to 64 in a single convalescent sample. RSV may be a more important cause of lower respiratory illness among the elderly in residential institutions than previously recognised.

Rubella in hospital employees.

In early 1982, 15 hospitals in Los Angeles County reported one or more serologically confirmed rubella cases among their employees. Secondary cases occurred at eight hospitals; overall, 56 cases were identified among employees, of which 28 were serologically confirmed. Testing of 2,061 employees revealed 1,770 (86%) with detectable antibody. A survey of 83 hospitals offering obstetrical services indicated only 42% (33 of 78) had an established rubella screening policy. Based on the results of this survey, the Los Angeles County Department of Health Services published recommendations for hospital rubella screening and immunization policies.

National case-control study of Kaposi's sarcoma and Pneumocystis carinii pneumonia in homosexual men: Part 1. Epidemiologic results.

To identify risk factors for the occurrence of Kaposi's sarcoma and Pneumocystis carinii pneumonia in homosexual men, we conducted a case-control study in New York City, San Francisco, Los Angeles, and Atlanta. Fifty patients (cases) (39 with Kaposi's sarcoma, 8 with pneumocystis pneumonia, and 3 with both) and 120 matched homosexual male controls (from sexually transmitted disease clinics and private medical practices) participated in the study. The variable most strongly associated with illness was a larger number of male sex partners per year (median, 61 for patients; 27 and 25 for clinic and private practice controls, respectively). Compared with controls, cases were also more likely to have been exposed to feces during sex, have had syphilis and non-B hepatitis, have been treated for enteric parasites, and have used various illicit substances. Certain aspects of a lifestyle shared by a subgroup of the male homosexual population are associated with an increased risk of Kaposi's sarcoma and pneumocystis pneumonia.

Rubella outbreak among hospital employees.

A rubella outbreak among medical staff on the obstetric service of a large Los Angeles hospital was studied. Fifteen cases of suspected rubella were reported among hospital personnel during a 2-month period in 1978. Of these, 4 were confirmed, 2 by viral isolation and serology and 2 by serologic study alone. A fifth case, the index, had a convalescent-phase serum with an elevated rubella hemagglutination inhibition (HAI) antibody titer. A list of 231 pregnant women who may have been exposed to any of the 15 suspect cases was assembled. The authors succeeded in contacting and obtaining postexposure sera for only 140 (61%) of the exposed women. Thirty-five (25%) of these women were without detectable rubella HAI antibody. A second serum sample was obtained from 93 women 2 to 3 weeks after the first, and no fourfold rises in titer were observed. To evaluate those with suspicious high stationary titers, 60 specimens were selected for immunoglobulin M (IgM) testing. Only 1 was positive for IgM antibody. A postexposure illness survey revealed that 20 (15%) of 130 women reported various rash-like illnesses after their visit to the hospital. There were no reports of affected offspring in any of the exposed women. Four hundred ten staff members submitted sera for antibody testing; 76 (19.2%) were without detectable rubella HAI antibody. This outbreak is discussed in light of recent changes in rubella epidemiology, and several recommendations for hospital policy are proposed.

Vaccine failures in the epidemiology and control of measles.

Data were employed from confirmed measles case reports and an immunization survey to estimate the apparent effectiveness of measles vaccine in Los Angeles County in 1976. We evaluated the age-specific proportions of our case load arising from persons erroneously thought to possess immunity. Thirty five per cent of our cases claimed to have had prior measles vaccination, and over 60 per cent of these reported having written records. Since community measles control programs rely on immunization records as the principal screening tool, the shortcomings observed need to be recognized.