RESUMEN

To determine factors associated with isosporiasis in persons with acquired immunodeficiency syndrome (AIDS) in Los Angeles County, data from the AIDS surveillance registry were analyzed for the eight-year period 1985-1992. Isosporiasis was reported in 127 (1.0%) of 16,351 persons with AIDS during the study period. Prevalence of infection was highest among foreign-born patients (3.2%), especially those from El Salvador (7.4%) and Mexico (5.4%), and in all persons of Hispanic ethnicity (2.9%). Persons with a history of Pneumocystis carinii pneumonia (PCP) were less likely than PCP-negative patients to have isosporiasis (0.2% and 1.4%, respectively, P < 0.01). A decrease in the prevalence of isosporiasis in patients negative for PCP was observed beginning in 1989 (P = 0.02). Prevalence decreased with age (P < 0.01, by chi-square test for trend). After controlling for multiple factors by logistic regression, isosporiasis was more likely to occur in foreign-born patients than in those born in the United States (adjusted odds ratio [OR] = 5.8, 95% confidence interval [CI] 3.4, 9.9, P < 0.001) and in Hispanics than in whites (non-Hispanics) (adjusted OR = 3.5, 95% CI 1.7, 7.2, P < 0.001). A prior history of PCP continued to be negatively associated with isosporiasis (adjusted OR = 0.2, 95% CI 0.1, 0.3, P < 0.001). Age and time remained independently associated with infection. These data suggest that isosporiasis among persons with AIDS in Los Angeles County may be related to travel exposure and/or recent immigration and that the use of trimethoprim-sulfamethoxazole (TMP-SMX) for PCP may effectively prevent primary infection or expression of latent isosporiasis. Physicians should have an increased index of suspicion for Isospora in AIDS patients with diarrhea who have immigrated from or traveled to Latin America, among Hispanics born in the United States, in young adults, and in those not receiving PCP prophylaxis. Food and water precautions should be advised and TMP-SMX prophylaxis considered for the prevention of Isospora infection for patients with human immunodeficiency virus infection who travel to Latin America and other developing countries.

Asunto(s)

Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Coccidiosis/epidemiología , Isospora , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Adolescente , Adulto , Anciano , Animales , Antimaláricos/uso terapéutico , Coccidiosis/tratamiento farmacológico , Etnicidad , Femenino , Humanos , Los Angeles/epidemiología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Vigilancia de la Población , Prevalencia , Sistema de Registros , Factores de Riesgo , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico

RESUMEN

We assessed the use of influenza vaccine in a cohort of HIV-infected patients during 1991 and 1992 in Los Angeles County. Influenza vaccination status and clinical and demographic data were obtained from medical records in three different outpatient clinics: a health maintenance organization (HMO), a public clinic and a private medical group. The overall proportion of patients immunized with influenza vaccine was 28%. Patients receiving medical care at the HMO were more likely to receive influenza vaccine (45%) than were patients at the public clinic (25%) or the private facility (13%). Higher immunization levels were also observed among patients with greater numbers of clinic visits for both years studied (p < 0.001). After we controlled for the number of outpatient visits, patients at the HMO and the public clinic were still more likely to receive influenza vaccine in both 1991 (adjusted relative risks 3.2 and 2.1, respectively) and 1992 (adjusted relative risks 1.7 and 1.8) compared with private clinic patients. Health-care providers should increase efforts to provide influenza vaccine to HIV-infected patients.

Asunto(s)

Infecciones por VIH/inmunología , Vacunas contra la Influenza/inmunología , Vacunación/estadística & datos numéricos , Femenino , Humanos , Masculino

RESUMEN

To determine the occurrence and factors associated with Cryptosporidium among persons with acquired immunodeficiency syndrome (AIDS) in Los Angeles County, data were analyzed from the AIDS surveillance registry for the 10-year period 1983-1992. Among 16,953 persons with AIDS, a total of 638 (3.8%) cryptosporidiosis cases were reported during the study period. The prevalence of cryptosporidiosis was higher in persons whose suspected human immunodeficiency virus (HIV) exposure category was through sexual contact (3.9%) than among persons in other HIV exposure categories (2.6%; P < 0.01) and in immigrants from Mexico (5.2%) than in American born patients (3.8%; P < 0.01). Blacks (2.7%) were less likely than whites (4.1%) and Latinos (4.2%) to be reported with cryptosporidiosis (P < 0.001). A temporal trend was observed from 1983 to 1986 when the prevalence decreased from 6.7% to 3.6% (P < 0.001, by chi-square test for trend). After controlling for confounding variables by stratified analysis, persons whose HIV exposure was sexual (adjusted odds ratio [OR] = 1.7, 95% confidence interval [CI] 1.3, 2.4, P < 0.01) and immigrants from Mexico (adjusted OR = 1.6, 95% CI 1.2, 2.1, P < 0.01) were more likely to have cryptosporidiosis. The negative association with black race remained significant (adjusted OR = 0.7, 95% CI 0.57, 0.96, P = 0.02). The prevalence of cryptosporidiosis decreased with age in gay and bisexual males (Mantel-Haenszel test for trend, P < 0.01) but not among female and heterosexual male cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Asunto(s)

Síndrome de Inmunodeficiencia Adquirida/complicaciones , Criptosporidiosis/epidemiología , Síndrome de Inmunodeficiencia Adquirida/transmisión , Adolescente , Adulto , Negro o Afroamericano , Factores de Edad , Bisexualidad , Distribución de Chi-Cuadrado , Niño , Preescolar , Intervalos de Confianza , Criptosporidiosis/complicaciones , Criptosporidiosis/transmisión , Femenino , Hispánicos o Latinos , Homosexualidad Masculina , Humanos , Los Angeles/epidemiología , Masculino , México/etnología , Persona de Mediana Edad , Oportunidad Relativa , Prevalencia , Sistema de Registros , Factores Sexuales , Conducta Sexual , Población Blanca

Asunto(s)

Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/etnología , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida/etnología , Negro o Afroamericano , Antivirales/uso terapéutico , Hispánicos o Latinos , Humanos , Registros Médicos , Cooperación del Paciente

RESUMEN

Thirty-three cases of locally acquired murine typhus were reported in Los Angeles County residents from May 1984 through February 1988. Only eight cases were reported over the previous 20-year period. Thirty (91%) cases resided within a suburban area encompassing approximately 50 km2 in northcentral Los Angeles or had contact with an animal from this area. Serologic testing (complement fixation and indirect fluorescent antibody) of selected animals in close association with human cases revealed a high prevalence of seropositivity among domestic cats and opossums. Nine (90%) of 10 resident cats tested had demonstrable antibody titers compared with none (0%) of 20 cats from a control area (P < 0.001). Suburban typhus cases were more likely than neighborhood controls to own a cat or dog (odds ratio = 6.9, 95% confidence interval = 1.8, 25.9, P = 0.002). Sixteen (42%) of 38 opossums trapped in close proximity to the residences of cases were seropositive versus none (0%) of 36 opossums from control areas (P < 0.001) A low frequency (2.8%) of seropositivity was found in commensal rodents, and the classic vector of murine typhus, Xenopsylla cheopis, was not found. Ectoparasite indices form seropositive opossums revealed heavy infestations with the cat flea, Ctenocephalides felis (mean flea count = 104.7), a species that readily bites humans. These data provide evidence that a suburban focus of murine typhus exists in Los Angeles that differs substantially from the classic transmission cycle, and that cats, opossums and C. felis may play an important role in the occurrence of human cases.

Asunto(s)

Enfermedades de los Gatos/epidemiología , Reservorios de Enfermedades , Zarigüeyas , Tifus Endémico Transmitido por Pulgas/epidemiología , Adolescente , Adulto , Anciano , Animales , Gatos , Niño , Infestaciones Ectoparasitarias/veterinaria , Femenino , Humanos , Los Angeles/epidemiología , Masculino , Mephitidae , Persona de Mediana Edad , Muridae , Prevalencia , Ratas , Siphonaptera , Tifus Endémico Transmitido por Pulgas/transmisión , Tifus Endémico Transmitido por Pulgas/veterinaria

RESUMEN

A surveillance system for cysticercosis was initiated in January 1988 in Los Angeles County to measure the incidence of the disease, to more accurately assess the level of locally acquired and travel-related infection, and to evaluate household contacts for intestinal tapeworm infection. In three years of surveillance (1988-1990), 138 incident cases were reported for an average crude annual incidence rate of 0.6 per 100,000 population. The highest rates were among Hispanics (1.6/100,000), most of whom were Mexican immigrants. Eight (5.8%) cases were fatal. Nine (6.5%) probable travel-associated cases occurred among persons born in the United States who had traveled to Mexico. Ten (7.2%) autochthonous cases of cysticercosis were documented. Taenia eggs were recovered more commonly in specimens from contacts with cysticercosis cases (1.1%) than in specimens from noncontact patients (0.2%). At least one Taenia tapeworm carrier was found among contacts of five (6.9%) of 72 cysticercosis patients. Carriers were more likely to be found among contacts of patients born in the United States (22.2%) than among those of foreign-born (4.8%) patients (odds ratio = 5.4) Cysticercosis causes appreciable morbidity and mortality in Los Angeles County, principally among Hispanic immigrants. However, these results indicate that both travel-acquired and locally acquired cysticercosis may be more common than previously recognized. Public health followup of cysticercosis cases, including screening of household contacts, can identify tapeworm carriers, who can be treated and removed as potential sources of further infection.

Asunto(s)

Portador Sano/epidemiología , Cisticercosis/epidemiología , Parasitosis Intestinales/epidemiología , Teniasis/epidemiología , Adolescente , Adulto , Anciano , Portador Sano/diagnóstico , Niño , Preescolar , Cisticercosis/diagnóstico , Familia , Femenino , Estudios de Seguimiento , Hispánicos o Latinos , Humanos , Incidencia , Lactante , América Latina , Los Angeles/epidemiología , Masculino , Americanos Mexicanos , Persona de Mediana Edad , Teniasis/diagnóstico , Viaje

RESUMEN

The recent discovery of cat fleas (Ctenocephalides felis) infected with a typhuslike rickettsia (designated the ELB agent) raises the question of whether similar rickettsial infections exist in wild cat flea populations. We verified the presence of the ELB agent and Rickettsia typhi in urban and suburban areas of Los Angeles, Calif. Opossums trapped in close proximity to the residences of human murine typhus cases in Los Angeles county and other areas within the city of Los Angeles were tested for the presence of typhus group rickettsiae by the polymerase chain reaction (PCR). The presence of rickettsiae in the spleen tissues of three opossums (n = 9) and in 66 opossum fleas (n = 205) was determined by PCR and was verified by dot blot and Southern transfer hybridization. Further analysis of the amplified PCR products generated by a series of primer pairs derived from either the 17-kDa antigen gene or the citrate synthase gene revealed that both R. typhi and the ELB agent were present in the tested samples. Dual infection was not noted in the samples; however, the fleas were infected with either R. typhi or the ELB agent. The presence of the ELB agent in the cat flea population may have implications for public health. Whether this agent is responsible for the mild cases of human murine typhus in urban and suburban areas of Los Angeles or in other endemic foci remains to be determined.

Asunto(s)

ADN Bacteriano/aislamiento & purificación , Zarigüeyas/microbiología , Rickettsia/aislamiento & purificación , Siphonaptera/microbiología , Tifus Endémico Transmitido por Pulgas/microbiología , Animales , Secuencia de Bases , Los Angeles , Datos de Secuencia Molecular , Zarigüeyas/parasitología , Reacción en Cadena de la Polimerasa , Rickettsia/genética , Rickettsia typhi/aislamiento & purificación

RESUMEN

In July and August 1988, an outbreak of gastroenteritis affected 44 of 60 (73%) persons from 5 separate swimming groups who had used the same swimming pool in Los Angeles. Cryptosporidium was identified in 5 of 8 (63%) stool specimens, and the clinical picture was consistent with Cryptosporidium infection. Resistance of Cryptosporidium to chlorine, an inadequately maintained pool filtration system, repeated exposure to pool water, and possible continuing pool contamination may have contributed to ongoing transmission. Cryptosporidium should be considered a potential etiologic agent of gastroenteritis associated with recreational water use.

Asunto(s)

Criptosporidiosis/epidemiología , Diarrea/epidemiología , Brotes de Enfermedades , Piscinas , Adolescente , Adulto , Animales , Estudios de Casos y Controles , Niño , Preescolar , Cryptosporidium/aislamiento & purificación , Diarrea/microbiología , Heces/microbiología , Humanos , Los Angeles/epidemiología , Persona de Mediana Edad

RESUMEN

Cysticercosis, a sometimes fatal ailment caused by larvae of the pork tapeworm Taenia solium, became a reportable disease in California in 1989. During the first year, from 1 April 1989 through 31 March 1990, 134 cases were reported to the California Department of Health Services. All of the 112 patients for whom laboratory diagnostic test data were obtained had neurocysticercosis. Nearly all (117) of the 127 patients whose race and ethnic background were known had a Hispanic background, and most of the 112 patients whose country of birth or prior residence was known had immigrated from T. solium-endemic countries. However, three of 11 patients born in the United States said they had never traveled outside the country, and it appears possible that indigenous transmission has been occurring. These findings affirm that neurocysticercosis should be included in the differential diagnosis of neurologic symptoms in patients who have immigrated from or traveled to T. solium-endemic countries, and also in those who have been in close contact with immigrants from endemic countries.

Asunto(s)

Cisticercosis/epidemiología , Adolescente , Adulto , Biopsia , California/epidemiología , Niño , Preescolar , Cisticercosis/diagnóstico , Cisticercosis/transmisión , Diagnóstico Diferencial , Emigración e Inmigración/estadística & datos numéricos , Femenino , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Lactante , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Tomografía Computarizada por Rayos X

RESUMEN

The incidence and characteristics of campylobacteriosis among patients with acquired immune deficiency syndrome (AIDS) in Los Angeles County were assessed by matching the Campylobacter and AIDS surveillance reporting registries for the years 1983-1987. Campylobacter infection was reported in 29 (0.7%) of 4,433 AIDS cases. The average annual incidence of Campylobacter among AIDS cases (519/100,000) exceeded the crude population rate by 39-fold and exceeded the rate among males aged 15-55 years by 35-fold. Campylobacter infection was more common in female AIDS patients than male patients (p = 0.065). A distinct seasonal variation was noted with peaks occurring in July and November. The median survival time for AIDS patients with Campylobacter (14 months) was lower than that for AIDS patients without Campylobacter (21 months); however, we were not able to assess potential confounders such as subsequent opportunistic infections or antiviral therapy and prophylactic regiment to validate this finding. Campylobacter cases with AIDS had higher rates of bacteremia and hospitalization than Campylobacter cases without AIDS. Attempts should be made to elucidate the sources of Campylobacter and other enteric infections among AIDS patients.

Asunto(s)

Síndrome de Inmunodeficiencia Adquirida/complicaciones , Infecciones por Campylobacter/complicaciones , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Adolescente , Adulto , Infecciones por Campylobacter/epidemiología , Infecciones por Campylobacter/mortalidad , Femenino , Humanos , Incidencia , Los Angeles/epidemiología , Masculino , Persona de Mediana Edad , Estaciones del Año , Sepsis/complicaciones , Sepsis/epidemiología , Tasa de Supervivencia

RESUMEN

In Los Angeles County from 1983-1988, rates of amebiasis declined 65 percent among White males 15-44 years. No such decline occurred among White females 15-44 years or White males less than 15. Reported acquired immunodeficiency syndrome (AIDS) cases in the district of highest AIDS incidence has followed the initial decline in amebiasis by four years. Amebiasis trends may be a useful predictor of human immunodeficiency virus (HIV) transmission and future rates of AIDS among gay men.

Asunto(s)

Síndrome de Inmunodeficiencia Adquirida/epidemiología , Amebiasis/epidemiología , Síndrome de Inmunodeficiencia Adquirida/transmisión , Adolescente , Adulto , Amebiasis/transmisión , Femenino , Humanos , Los Angeles , Masculino , Factores Sexuales

RESUMEN

An outbreak of shigellosis associated with swimming at a human-made lake during the Labor Day weekend occurred in Los Angeles County in 1985. Sixty-eight persons had onset of diarrheal illness within 1 week following exposure at the recreational site. Thirty-three of these cases were culture-confirmed as shigellosis (29 Shigella sonnei, 4 Shigella boydii). Fifteen persons were hospitalized. Illness was highly associated with water contact, specifically swallowing water while swimming (P less than 0.001) and age less than 15 years (P less than 0.001). Water samples from the swimming area had high fecal coliform counts; however, dye testing showed no evidence of sewage contamination. Direct bather contamination of the swimming area may have occurred in the context of large crowds, inadequate restroom facilities, poor water exchange, and the absence of a mechanism of disinfection.

Asunto(s)

Brotes de Enfermedades , Disentería Bacilar/epidemiología , Microbiología del Agua , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Recuento de Colonia Microbiana , Disentería Bacilar/etiología , Enterobacteriaceae/crecimiento & desarrollo , Femenino , Agua Dulce , Humanos , Lactante , Los Angeles/epidemiología , Masculino , Factores de Riesgo , Factores Sexuales , Shigella/aislamiento & purificación , Natación

RESUMEN

A survey for enteric infections in 140 asymptomatic homosexual men who attended a community clinic revealed a high prevalence of infection with Entamoeba histolytica (27.1 per cent) and Giardia lamblia (15.7 per cent). In contrast, the prevalence of elevated indirect hemagglutination (IHA) titers (greater than or equal to 1:128), which indicate invasive amebiasis, was low (5.7 per cent). Our findings suggest that only a limited amount of invasive amebic disease is occurring in this group of homosexual men.

Asunto(s)

Amebiasis/epidemiología , Homosexualidad , Adolescente , Adulto , Amebiasis/diagnóstico , California , Entamoeba histolytica/aislamiento & purificación , Métodos Epidemiológicos , Heces/microbiología , Giardia/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad

RESUMEN

An outbreak of influenza A in nursing home residents is reported and other studies of influenza vaccine effectiveness in elderly populations are reviewed. The outbreak occurred in a Los Angeles nursing home between February and March 1983. Of the 87 residents, 46 (53%) were affected with influenza-like illness. Attack rates were similar between immunized and unimmunized residents (52% versus 58%), and yielded a vaccine effectiveness estimate of 10%. No additional protection could be demonstrated in residents who received vaccine for two consecutive years. Seven persons died (mortality rate of 8.1%); the mortality rate was greater in the unimmunized (15.8%) than in the immunized (6.2%). Because this study and other field studies of influenza vaccine are limited in precision and power, a statistical summary of the various studies was constructed. Summarizing the studies of institutionalized elderly (in hospitals and nursing and retirement homes) yielded an estimate of 74% for the average vaccine effectiveness in mortality reduction, and an estimate of 33% for the average effectiveness in preventing clinical illness. For the non-institutionalized elderly, the corresponding estimates were 47% for mortality, and 5% for clinical illness. Despite the obvious limitations of such summaries, it seems reasonable to conclude that influenza vaccines have on the average been of clear benefit in the institutionalized elderly, while the benefits in the non-institutionalized elderly have been less dramatic and may warrant further investigation.

Asunto(s)

Gripe Humana/epidemiología , Anciano , California , Brotes de Enfermedades , Métodos Epidemiológicos , Humanos , Vacunas contra la Influenza/uso terapéutico , Gripe Humana/mortalidad , Gripe Humana/prevención & control , Casas de Salud

RESUMEN

Four hundred ninety-seven patients were identified as having been treated for cysticercosis at four hospitals in Los Angeles during the 11-year period 1973 through 1983. Eleven deaths were recorded. Over 90% of these patients were Hispanics in productive age groups; the majority were Mexican by nationality. Hospitalizations were generally short, and readmissions for recurrence of symptoms or complications of therapy occurred in only 14% of patients. Cysticercosis was diagnosed in 12 US citizens who had no history of travel to countries considered traditionally endemic for Taenia solium taeniasis/cysticercosis. A dramatic rise in numbers of cases was observed after 1977, appearing to plateau at approximately 80 cases per year in 1981. The increase in cases beginning in 1977 coincided with the introduction of the computed tomographic scan.

Asunto(s)

Cisticercosis/epidemiología , Adolescente , Adulto , Anciano , California , Niño , Preescolar , Cisticercosis/parasitología , Cisticercosis/terapia , Etnicidad , Heces/parasitología , Femenino , Hospitalización , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Readmisión del Paciente , Viaje

RESUMEN

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.

Asunto(s)

Brotes de Enfermedades/epidemiología , Neumonía Viral/epidemiología , Infecciones por Respirovirus/epidemiología , Anciano , Anticuerpos Antivirales/análisis , California , Femenino , Hogares para Ancianos , Humanos , Masculino , Casas de Salud , Virus Sincitiales Respiratorios/inmunología