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Infection with Baylisascaris procyonis roundworms is rare but often fatal and typically affects children. We attempted to determine parameters of viability and methods of inactivating the eggs of these roundworms. Loss of viability resulted when eggs were heated to 62°C or desiccated for 7 months but not when frozen at -15°C for 6 months. [ABSTRACT FROM AUTHOR]

Background: Despite its elimination in the early 1950s, about 1700 cases of malaria are reported in the US every year. Few studies have quantified the direct and indirect costs of imported malaria in the US., Methods: Disparities in the mean and total hospital days, hospital charges, and hospital costs for malaria-related hospitalizations in the US by demographic, clinical, species, financial, geographic, and institutional characteristics were examined using the 2000-2014 Nationwide Inpatient Sample (NIS). Trends and potential predictors for length of stay and hospital charges and costs were identified using negative binomial regression and linear regression, respectively., Results: From 2000 to 2014, 22,029 malaria cases resulted in 95,948 hospital days for malaria-related hospitalizations, $176,391,466 in total hospital costs, and $555,435,849 in total charges. Mean charges increased significantly over the study period. Males, Blacks, and patients aged 25-44years accounted for the highest direct and indirect costs. Older age and having severe malaria was associated with a longer length of stay. Older age, severe malaria, HIV infection, and longer lengths of stay were associated with higher charges and costs., Conclusions: Malaria resulted in substantial direct and indirect costs in the US. Primary and secondary prevention measures should be prioritized among high-risk groups to reduce the economic burden., (Published by Elsevier Ltd.)

Background: Factors associated with the development of severe malaria have not been well described for cases occurring in the United States (US)., Methods: Severe malaria hospitalizations data from the 2000-2014 Nationwide Inpatient Sample were analyzed. Frequencies were reported by demographic, clinical, species, financial, geographic, and institutional characteristics, and trends and disparities were identified. Logistic regression models were used to identify potential predictors for severe disease among those with malaria., Results: From 2000 to 2014, there were an estimated 4823 severe malaria cases, representing 21.9% of all malaria-related hospitalizations, including 182 severe malaria deaths. Severe malaria was most common among inpatients who were male, Black, aged 45-64 years, and hospitalized in the South Atlantic division of the US. Older age was associated with higher odds of severe malaria, cerebral malaria, ARDS, severe anemia, and renal failure. Males had higher odds of developing renal failure and jaundice, while females had higher odds of developing severe anemia. HIV infection was associated with increased odds of severe malaria, severe anemia, and renal failure., Conclusion: Primary and secondary prevention measures, such as pre-travel consultations, chemoprophylaxis, and early diagnosis and treatment, should be emphasized and improved among high-risk prospective travelers to malaria endemic countries., (Published by Elsevier B.V.)

Purpose: Helping children living with HIV (CLH) to attain an optimum quality of life is an important goal for HIV programs around the world. Our principal objectives were to determine the association of HIV infection with different domains of health-related quality of life (HRQoL) among 8- to 15-year-old CLH in India and to compare the HRQoL parameters between CLH and HIV-negative children born to HIV-infected parents ("HIV-affected"). We also assessed whether antiretroviral therapy (ART) and CD4 lymphocyte counts were associated with HRQoL among CLH., Methods: Using the "Quality of Life (health-related) of Children Living with HIV/AIDS in India" instrument, we interviewed 199 CLH and 194 HIV-affected children from three districts of West Bengal, India. Participants were asked to quantify the difficulties faced by them in six HRQoL domains: physical, emotional, social, school functioning, symptoms, and discrimination., Results: The mean age of the participants was 11.6 (SD ± 2.5) years. CLH, compared to HIV-affected children, had poorer scores on all HRQoL domains except 'discrimination.' Among CLH, there were no significant differences in HRQoL domain scores (except in the 'discrimination' domain) between ART-treated and -untreated groups. CD4 lymphocyte count was found to be a significant positive predictor of the 'symptom' scale score., Conclusions: In India, interventions for CLH mostly focus on biological disease. However, the current study revealed that HRQoL among CLH was much poorer than that of a socio-demographically comparable group. Culturally and developmentally appropriate psychosocial support measures for Indian CLH are urgently needed.

Few data are available on the burden of malaria hospitalization in the United States. Study of malaria using hospital-based data can better define the impact of malaria and help inform prevention efforts. U.S. malaria cases identified from hospitalization discharge records in the 2000-2014 Nationwide Inpatient Sample were examined. Frequencies and population rates were reported by demographics, infecting species, clinical, financial, institutional, geographic, and seasonal characteristics, and disparities were identified. Time trends in malaria cases were assessed using negative binomial regression. From 2000 to 2014, there were an estimated 22,029 malaria-related hospitalizations (4.88 per 1 million population) in the United States, including 182 in-hospital deaths and 4,823 severe malaria cases. The rate of malaria-related hospitalizations did not change significantly over the study period. The largest number of malaria-related hospitalizations occurred in August. Malaria-related hospitalizations occurred disproportionately among patients who were male, black, or 25-44 years of age. Plasmodium falciparum accounted for the majority of malaria-related hospitalizations. On average, malaria patients were hospitalized for 4.36 days with charges of $25,789. Patients with a malaria diagnosis were more often hospitalized in the Middle Atlantic and South Atlantic census divisions, urban teaching, private not-for-profit, and large-bed-size hospitals. Malaria imposes a substantial disease burden in the United States. Enhanced primary and secondary prevention measures, including strategies to increase the use of pretravel consultations and prompt diagnosis and treatment are needed.

Cysticercosis has become increasingly recognized as an important infection in the United States in recent decades. Despite its potential impact, there is a lack of comprehensive information on the nationwide burden of disease. To better define the burden of cysticercosis in the United States, we analyzed in-patient records using the Nationwide Inpatient Sample for 1998-2011 to estimate cysticercosis-related hospitalizations and patient/institutional characteristics. There were an estimated 33,060 (95% confidence interval [95% CI] = 29,610.5-36,510.3) cysticercosis-related hospitalizations nationwide, representing a hospitalization rate of 8.03 per million population. The highest proportion of cases were male (54.8%), Hispanic (62.0%), aged 18-44 (58.8%), and occurred in the West (45.1%). An estimated 459 deaths occurred, representing an in-hospital case-fatality rate of 1.4%. These findings indicate the burden of cysticercosis-related hospitalizations in the United States is considerable and may be greater than currently appreciated. Cysticercosis should be a nationally reportable disease., (© The American Society of Tropical Medicine and Hygiene.)

Cysticercosis is a potentially fatal and preventable neglected parasitic infection caused by the larval form of Taenia solium. Patients with symptomatic disease usually have signs and symptoms of neurocysticercosis, which commonly manifest as seizures or increased intracranial pressure. Although there are many persons living in the United States who emigrated from highly disease-endemic countries and there are foci of autochthonous transmission of the parasite in the United States, little is known about burden and epidemiology of the disease in this country. In addition, despite advances in the diagnosis and management of neurocysticercosis, there remain many unanswered questions. Improving our understanding and management of neurocysticercosis in the United States will require improved surveillance or focused prospective studies in appropriate areas and allocation of resources towards answering some of the key questions discussed in this report.

Background: Congenital cytomegalovirus (CMV) infection is the most common intrauterine infection in the United States disproportionately affecting minority races and those of lower socio-economic class. Despite its importance there is little information on the burden of congenital CMV-related mortality in the US. To measure congenital CMV-associated mortality in the US and assess possible racial/ethnic disparities, we reviewed national death certificate data for a 17-year period., Methods: Congenital CMV-associated deaths from 1990 through 2006 were identified from multiple-cause-coded death records and were combined with US census data to calculate mortality rates., Results: A total of 777 congenital CMV-associated deaths occurred over the 17-year study period resulting in 56,355 years of age-adjusted years of potential life lost. 71.7% (557) of congenital CMV-associated deaths occurred in infants (age less than 1 year). Age-adjusted mortality rates stratified by race/ethnicity revealed mortality disparities. Age-adjusted rate ratios were calculated for each racial/ethnic group using whites as the reference. Native Americans and African Americans were 2.34 (95% CI, 2.11-2.59) and 1.89 (95% CI, 1.70-2.11) times respectively, more likely to die from congenital CMV than whites. Asians and Hispanics were 0.54 (95% CI, 0.44-0.66) and 0.96 (95% CI, 0.83-1.10) times respectively, less likely to die from congenital CMV than whites., Conclusions/significance: Congenital CMV infection causes appreciable mortality in the US exacting a particular burden among African Americans and Native Americans. Enhanced surveillance and increased screening are necessary to better understand the epidemiology of congenital CMV infection in addition to acceleration of vaccine development efforts.

Introduction: Sepsis is the 10th leading cause of death in the United States. The National Center for Health Statistics' multiple-cause-of-death (MCOD) dataset is a large, publicly available, population-based source of information on disease burden in the United States. We have analysed MCOD data from 1999 to 2005 to investigate trends, assess disparities and provide population-based estimates of sepsis-associated mortality during this period., Methods: Sepsis-associated deaths occurring in the United States from 1999 to 2005 were identified in MCOD data using International Classification of Disease, 10th Revision (ICD-10) codes. Population-based mortality rates were calculated using bridged-race population estimates from the National Center for Health Statistics. Comparisons across age, sex and racial/ethnic groups were achieved by calculating mortality rate ratios., Results: From 1999 to 2005 there were 16,948,482 deaths in the United States. Of these, 1,017,616 were associated with sepsis (6.0% of all deaths). The age-adjusted rate of sepsis-associated mortality was 50.37 deaths per 100,000 (95% confidence interval (CI) = 50.28 to 50.47). There were significant disparities in sepsis-associated mortality in race/ethnicity and sex groups (P < 0.0001). After controlling for age, Asians were less likely than whites to experience sepsis-related death (rate ratio (RR) = 0.78, 95% CI = 0.77 to 0.78), while Blacks (RR = 2.24, 95% CI = 2.23 to 2.24), American Indians/Alaska Natives (RR = 1.24, 95% CI = 1.24 to 1.25) and Hispanics (RR = 1.14, 95% CI = 1.13 to 1.14) were more likely than whites to experience sepsis-related death. Men were at increased risk for sepsis-associated death in all race/ethnicity categories (RR = 1.27, 95% CI = 1.27 to 1.28), but the degree of increased susceptibility associated with being male differed among racial/ethnic groups (P < 0.0001). Although crude sepsis-associated mortality increased by 0.67% per year during the study period (P < 0.0001), the age-adjusted mortality rate decreased by 0.18% per year (P < 0.01)., Conclusions: The rapid rise in sepsis mortality seen in previous decades has slowed, but population ageing continues to drive the growth of sepsis-associated mortality in the United States. Disparities in sepsis-associated mortality mirror those previously reported for sepsis incidence. Sepsis in Asians, Hispanics and American Indian/Alaska Natives should be studied separately because aggregate measures may obscure important differences among these groups.

Trichomonas vaginalis has long been recognized as one of the most prevalent sexually transmitted infections. However, it is only in recent years that it has been appreciated that Trichomonas may play a critical role in amplifying human immunodeficiency virus (HIV) transmission. Given the evidence that T. vaginalis likely promotes HIV infection, the apparent high level of Trichomonas infection in the African-American community is cause for concern. Even if T. vaginalis increases the risk of HIV transmission by a small or modest amount, it translates into a sizable population effect since Trichomonas is so common in this community. Therefore, control of trichomoniasis may represent an important avenue of control for the prevention of HIV transmission, particularly among African-Americans.

Objectives: Two of the major diagnostic methods for Trichomonas vaginalis, wet mount and culture, rely on the continued viability of the organism. Methods to increase the viability of T. vaginalis in urine are needed., Goal: The goal of this study was to develop a method that increases the time of viability of T. vaginalis in urine., Study Design: Urine samples were inoculated with trichomonads, held at either room temperature or 37 degrees C, and processed through a column and frit, which was then placed in either a tube of culture medium containing antibiotics or a TV InPouch., Results: The column and polyethylene frit system was found to increase the duration of viability for T. vaginalis from urine specimens at least 6-fold., Conclusion: This novel method, which uses a column and frit system to increase the duration of viability of the organism, has the potential to increase the sensitivity of diagnostic tests.

Cysticercosis has emerged as a cause of severe neurologic disease in the United States. We evaluated cysticercosis-related deaths in the United States for 1990-2002 by race, sex, age, state of residence, country of birth, and year of death. A total of 221 cysticercosis deaths were identified. Mortality rates were highest for Latinos (adjusted rate ratio [ARR] 94.5, relative to whites) and men (ARR = 1.8). The mean age at death was 40.5 years (range 2-88). Most patients (187 [84.6%]) were foreign born, and 137 (62%) had emigrated from Mexico. The 33 US-born persons who died of cysticercosis represented 15% of all cysticercosis-related deaths. The cysticercosis mortality rate was highest in California, which accounted for = 60% of all deaths. Although uncommon, cysticercosis is a cause of premature death in the United States. Fatal cysticercosis affected mainly immigrants from Mexico and other Latin American countries; however, US-born persons were also affected.

The impact of the viability of Trichomonas vaginalis in urine on wet mount, culture, and PCR methods was assessed. To minimize the chance of false-negative results, urine specimens should be processed within 30 min of specimen collection and maintained at 37 degrees C, since temperature appears to affect the viability of Trichomonas.

Baylisascaris procyonis, a parasitic infection of raccoons, causes severe neurologic and ocular disease in humans when infectious eggs from raccoon feces are ingested. In the absence of a serologic test, definitive diagnosis is challenging but can be made by isolation of larvae in brain biopsy, direct visualization of the worm in the eye, or exclusion of other potential causes of eosinophilic meningoencephalitis. Currently, no effective treatment has been identified, making preventive efforts critical.

Baylisascaris procyonis, a parasitic infection of raccoons, causes severe neurologic disease in humans when infective eggs from raccoon feces are ingested. Definitive diagnosis is challenging, but can be made by isolation of larvae in brain biopsy or exclusion of other potential causes of eosinophilic meningoencephalitis. Prevention efforts are critical due to the lack of effective treatment.

Cysticercosis is an increasingly important disease in the United States, but information on the occurrence of related deaths is limited. We examined data from California death certificates for the 12-year period 1989-2000. A total of 124 cysticercosis deaths were identified, representing a crude 12-year death rate of 3.9 per million population (95% confidence interval [CI] 3.2 to 4.6). Eighty-two (66%) of the case-patients were male; 42 (34%) were female. The median age at death was 34.5 years (range 7-81 years). Most patients (107, 86.3%) were foreign-born, and 90 (72.6%) had emigrated from Mexico. Seventeen (13.7%) deaths occurred in U.S.-born residents. Cysticercosis death rates were higher in Latino residents of California (13.0/106) than in other racial/ethnic groups (0.4/106), in males (5.2/106) than in females (2.7/106), and in persons >14 years of age (5.0/106). Cysticercosis is a preventable cause of premature death, particularly among young Latino persons in California and may be a more common cause of death in the United States than previously recognized.

To identify the frequency of and factors associated with early detection of HIV infection in Los Angeles County, data were evaluated from interviews of a population-based sample of adult persons with AIDS. Early detection was defined as greater than 5 years between the first reported positive HIV test and an AIDS diagnosis. The associations between early detection and sociodemographic and behavioral factors were assessed for the period January 1997 through June 2002. Over the study period, only 20% (253/1268) of persons interviewed met the criterion for early detection. Early HIV detection was less likely for women (adjusted odds ratio [AOR] = 0.6, 95% confidence interval [CI]: 0.4, 0.9), blacks (AOR = 0.5, 95% CI: 0.4, 0.8), foreign-born Latinos (AOR = 0.2, 95% CI: 0.1, 0.3), U.S.-born Latinos (AOR = 0.3, 95% CI: 0.2, 0.6, and heterosexuals (AOR = 0.5, 95% CI: 0.3, 0.7). Trends of increasing early detection with older age groups (p < 0.001) and higher educational levels (p < 0.001) were also observed. Our findings indicate an overall low level of early HIV detection and suggest that major sociodemographic and risk group disparities exist in the likelihood of early detection among HIV-infected persons in Los Angeles. These differences have important implications for reducing the level of community HIV transmission and for improving individual health outcomes among people with HIV. Aggressive efforts are needed to expand HIV testing and early detection for women, minorities, heterosexuals, younger age groups, and persons of lower education. Links to treatment and behavioral intervention programs should accompany such expanded testing efforts.

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.

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.

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)

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.