Community-acquired group A streptococcal deaths in Los Angeles County.
Explore the source record for details and available documents.
Adult↗
Biomedical subjects
S H Waterman
Publications and source records attributed to S H Waterman.
Declining rates of amebiasis in Los Angeles County: a sentinel for decreasing acquired immunodeficiency syndrome (AIDS) incidence?
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.
Acquired Immunodeficiency Syndrome↗
Shigellosis associated with recreational water contact in Los Angeles County.
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.
Adolescent↗
Chloramphenicol-resistant Salmonella newport traced through hamburger to dairy farms. A major persisting source of human salmonellosis in California.
Animal-to-human transmission of drug-resistant salmonella and the role of antimicrobial use in food animals in the emergence of these bacteria are controversial subjects. Investigation of a 4.9-fold increase in Salmonella newport isolations from Californians in 1985 showed that 87 percent of the isolates had an unusual antimicrobial-resistance pattern (including chloramphenicol resistance) and a single, identical plasmid. Interviews of 45 patients and 89 matched controls in Los Angeles County showed that illness was associated with penicillin or tetracycline use during the month before onset (P less than 0.001) and with eating ground beef during the week before onset (P = 0.052). The epidemic strain was isolated from hamburger products eaten by cases, abattoirs where the animals from which the meat came were slaughtered, dairies that sent cows for slaughter on days when culture-positive products were processed, and ill dairy cows. Isolation of salmonella from beef carcasses in abattoirs correlated with the proportion of dead or moribund animals received for slaughter (r = 0.60, P less than 0.05). Isolation of chloramphenicol-resistant salmonella from dairy farms was associated with the use of chloramphenicol at those dairies. We conclude that food animals are a major source of antimicrobial-resistant salmonella infections in humans and that these infections are associated with antimicrobial use on farms.
Abattoirs↗
Staphylococcal food poisoning on a cruise ship.
Two waves of vomiting and/or diarrhoea affected approximately 215 of the 715 passengers on a Caribbean cruise ship. The outbreak was independently associated with eating cream-filled pastries at two separate meals. Staphylococcus aureus phage type 85/+ was isolated from cases and pastry cooks, but not from controls. This is the first well-documented outbreak of staphylococcal food poisoning on a cruise ship.
Disease Outbreaks↗
Breast-feeding children in the household as a risk factor for cholera in rural Bangladesh: an hypothesis.
Vibrio cholerae 01 produces symptomatic and asymptomatic infections. In this study, we investigated a cholera epidemic in northern Bangladesh to specifically search for risks of developing symptomatic infection. A case-control study in six villages found that cases were more likely than controls to have in their family a child who was still breast-feeding and who had been asymptomatic during the epidemic. Among 24 case-control pairs with cholera-like diarrhea as cases, there were 11 discordant for the presence of such a child in the family, in 9 of them, the child was in the case-family (relative risk = 4.5, p = 0.033). Among 13 case-control pairs with laboratory-confirmed cholera as cases, there were 7 discordant for the presence of a breast-feeding child, and in 6 of them, the child was in the case-family (relative risk = 6, p = 0.06). Breast-feeding children in this area are usually kept naked, and defecate onto a cloth pad held against their buttocks by a family member who may be repeatedly exposed to the soiled cloth. Symptomatic infection with V. cholerae may depend on exposures to situations that augment the ingested dose of V. cholerae, and these findings led us to hypothesize that breast-feeding children, if infected, may play a substantial role (attributable risk = 55%) in facilitating such transmission in rural Bangladesh.
Adolescent↗
A case of natural concurrent human infection with two dengue viruses.
The first documented case of concurrent human infection with 2 dengue viruses is reported. Dengue 1 and 4 viruses were isolated from the serum of a 16-year-old male during the 1982 outbreak in Puerto Rico. The illness was mild and does not support the hypothesis that double infection with dengue viruses leads to more severe hemorrhagic disease.
Adolescent↗
Low rates of antigen detection and virus isolation from the peripheral blood leukocytes of dengue fever patients.
We evaluated direct fluorescent antibody (FA) testing of peripheral blood leukocytes (PBL) from patients in Puerto Rico with serologically and/or virologically confirmed dengue fever as a possible rapid diagnostic test and compared rates of dengue virus isolation from PBL with the rates from plasma or serum using the mosquito inoculation technique. Dengue antigen was detected in the PBL of only 1 of 19 patients with confirmed dengue. Virus was isolated from 3 of 19 PBL specimens and from 6 of 19 acute-phase serum or plasma samples. Four viruses were obtained from serum or plasma only and 1 isolate came from PBL only. We conclude that FA testing of PBL from dengue fever patients has little promise as a rapid diagnostic technique. Despite small numbers, our data suggest that virus isolation from PBL is less sensitive than that from serum or plasma. Our results differ considerably from those of previous studies of dengue hemorrhagic fever patients conducted in Thailand.
Antibodies, Viral↗
Dengue transmission in two Puerto Rican communities in 1982.
Paired serologic, entomologic, and environmental surveys were performed in two Puerto Rican communities, Salinas and Manatí, in summer and fall 1982. Paired samples on 434 persons in Salinas and 324 persons in Manatí showed recent dengue infection rates of 35% and 26%, respectively. Ae. aegypti larval indices were higher in Salinas than in Manatí but were relatively high throughout both communities. Breteau indices in neighborhoods ranged from 43 to 172, and infection rates in the neighborhoods were 22% to 45%. With a multivariate technique, we analyzed possible associations of environmental variables with dengue incidence and prevalence of dengue antibody. Wood-constructed housing and low socioeconomic status were among the variables significantly associated with dengue incidence. Predictors of dengue antibody prevalence included socioeconomic level, tree height, shade, and window and door screens. Recent dengue infections clustered within the sampled members of households (P less than 0.05, binomial test). An estimated 35% of dengue infections were symptomatic, and no serious illnesses were reported. The potential for high dengue infection rates in Puerto Rico will continue unless substantial reductions in vector populations are achieved. Targeting dengue surveillance and vector control activities in areas with demonstrated environmental risk factors may limit transmission during future outbreaks.
Adolescent↗
Acute hemorrhagic conjunctivitis in Puerto Rico, 1981-1982.
In late 1981, the Western Hemisphere's pandemic of acute hemorrhagic conjunctivitis spread to Puerto Rico. Over 6,000 cases of conjunctivitis were reported to the Puerto Rico Department of Health from November 1981 to March 1982. Enterovirus 70 was isolated from one of 19 eye-swab specimens tested, and 10 of 13 (77%) individuals with acute hemorrhagic conjunctivitis had neutralizing antibody titers to enterovirus 70 of greater than or equal to 1:4. These data suggest that enterovirus 70 was the etiologic agent of the acute hemorrhagic conjunctivitis outbreak in Puerto Rico. In a study of a lower middle socioeconomic sector with relatively intense transmission, 152 of 670 (23%) persons reported illness consistent with acute hemorrhagic conjunctivitis. The highest attack rate was in the 5- to 14-year-old group (30%), and a disproportionate number of household index cases were in the predominantly school age group (5-19 years old). Twelve per cent (3/25) of asymptomatic household contacts of acute hemorrhagic conjunctivitis cases had sera with neutralizing antibody to enterovirus 70. Retrospective surveillance through ophthalmologists and neurologists identified one patient with a neurologic complication, a seventh nerve palsy temporally associated with recent enterovirus 70 infection. Household transmission was significantly associated with crowding and sharing of beds (p less than 0.05). This and other recent studies in Florida suggest that school age children play an important role in the transmission of acute hemorrhagic conjunctivitis. This study also suggests that asymptomatic enterovirus 70 infection is uncommon, and that in Puerto Rico, neurologic complications associated with acute hemorrhagic conjunctivitis were quite rare.
Adolescent↗
Dengue fever in the United States. A report of a cluster of imported cases and review of the clinical, epidemiologic, and public health aspects of the disease.
In the United States during 1981, fourteen state health departments reported a total of 44 imported cases of dengue fever. Most originated in the Caribbean, where dengue type 4 has reached pandemic proportions. Because the mosquito vector for dengue is abundant throughout the southeast and imported cases continue to occur, the possibility exists for indigenous dengue transmission. We report a cluster of imported dengue type 1 cases in Florida, discuss the clinical, epidemiologic, and public health aspects of the disease, and make recommendations as to how clinicians can assist public health officials in minimizing the risk of indigenous dengue transmission in the United States.
Adult↗
Fluorescent antibody techniques applied to the identification of dengue virus in infected tissue.
We evaluated an indirect fluorescent antibody (FA) method for the detection of dengue virus antigen in infected mouse tissues. The biotin-avidin system [unlabeled antiviral antibody, biotinyl-anti-IgG and fluorescein conjugated avidin D(biotin-avidin system)] theoretically enhances the sensitivity of the FA method by amplifying the number of fluorescein particles attached indirectly to antigen. Using antibody endpoint titers in dengue-infected suckling mouse brain as an assay for sensitivity, we compared this three-step technique with the standard direct and two-step indirect FA techniques. Comparative tests were done on frozen sections of mouse brains with infectivity titers between 4.5 and 8.3 log10 LLC-MK2 cell PFU/g. Antibody endpoint titers with the biotin-avidin system were 2- to 8-fold higher than those obtained with the indirect and direct fluorescent antibody systems. The biotin-avidin system may be useful for rapid postmortem diagnosis of some fatal dengue hemorrhagic fever-dengue shock syndrome cases and perhaps also for early diagnosis of dengue by examination of leukocytes or biopsy material.
Animals↗
Prevalence of antibody to Trypanosoma cruzi among blood donors in Los Angeles, California.
Transfusion-associated Chagas' disease is a serious public health problem in Central and South America. With the recent influx of immigrants from Chagas' disease-endemic areas, concern about the risk of disease from blood transfusion has increased in the United States. To assess the prevalence of Trypanosoma cruzi infection in one area, 1024 consecutive blood donations from 988 voluntary blood donors at a medical center in Los Angeles County were screened serologically. The median age of donors screened was 32.5 years; 53.4 percent were male, and 38.4 percent were born in Chagas' disease-endemic countries. All donor sera were tested by complement fixation (CF) and indirect immunofluorescence (IIF) tests. A radioimmunoprecipitation assay (RIPA) was also done on all sera from CF- or IIF-reactive donors and an equal number of sera from nonreactive donors. A second serum specimen was obtained, and interviews were completed for 18 (67%) of 27 donors with an initial CF titer greater than or equal to 8 or an IIF titer greater than or equal to 64. The overall seroreactivity (by CF and IIF) was 1.1 percent (11/988). One donor (0.1%) had antibody specific to the 72- and 90-kDa antigens of T. cruzi on RIPA. Seven recipients of blood components from the seroreactive donors were located and were seronegative at 3 to 6 months. Seroreactive donors were 3.6 times more likely to have been born or to have resided in Mexico or Central America, 8.7 times more likely to have donated blood in the past, and 11.8 times more likely to have a history of malaria prophylaxis or treatment.
Adolescent↗
Chlamydia trachomatis infection among Hispanic women in the California-Mexico border area, 1993: establishing screening criteria in a primary care setting.
BACKGROUND: Chlamydia prevalence and transmission patterns in California-Mexico border communities are unknown, and selective screening strategies for Hispanic populations have not been evaluated. GOAL OF THIS STUDY: To determine chlamydia prevalence among Hispanic women in the California-Mexico border area and established screening criteria. STUDY DESIGN: This was a cross-sectional prevalence survey of family planning/prenatal Hispanic clients (n = 2378) in San Diego and Imperial Counties, California, and Tijuana, Mexico. RESULTS: Overall, chlamydia prevalence was 3.2% (3.3% in California; 2.1% in Mexico). Women born in Mexico or those who visited Mexico for at least 1 week in the recent past had a prevalence rate similar to women without those characteristics. Multivariate analysis showed that young age (less than 25 years old), unmarried status, or having clinical signs of a chlamydia syndrome (primarily cervicitis) or vaginosis independently predicted chlamydia infection. Applying minimum screening criteria recommended by the Centers for Disease Control would require screening less than half of the clients. However, only 69% of infections would be identified. Using survey-based criteria (less than 25 years old, unmarried, and clinical signs of a chlamydia syndrome) would require screening 64% of clients, but would identify 92% of those infected. CONCLUSION: Chlamydia prevalence among Hispanic women seeking reproductive healthcare was similar (< 5%) on both sides of the California-Mexico border. Among Hispanic women, using easily obtained demographic data (age and marital status) and clinical signs (primarily cervicitis), an effective selective screening strategy can be implemented.
Adult↗
The absence of dengue virus in the skin lesions of dengue fever.
Patients with confirmed dengue infection were studied in an attempt to elucidate the cause of the eruption of dengue fever. Punch biopsies of lesional skin were obtained and processed for the presence of viral antigen and immune globulins by the direct fluorescent antibody test. Another biopsy specimen and the acute sera were processed for virus isolation. Although virus was isolated from the serum of two patients, isolation attempts from the biopsy specimens of all four patients were negative. Fluorescent antibody studies revealed no evidence of either viral antigen or immune globulins in lesional skin. Although limited, the data suggest that the maculopapular rash of dengue fever may be caused by some mechanism other than direct viral infection of the skin or involvement of immune globulins.
Adolescent↗
The impact of health communication and enhanced laboratory-based surveillance on detection of cyclosporiasis outbreaks in California.
We investigated the timing of diagnosis, influence of media information on testing for Cyclospora, and the method used to identify cases during eight cyclosporiasis outbreaks in California in spring of 1997. We found that Internet information, media reports, and enhanced laboratory surveillance improved detection of these outbreaks.
Animals↗
Measles reporting completeness during a community-wide epidemic in inner-city Los Angeles.
A study was undertaken to determine the extent of measles underreporting among preschool-age children. In two community surveys conducted in inner-city Los Angeles during 1990 and 1991, respondents were asked whether preschool-age children in their households had ever been ill with measles. Information about measles episodes was obtained and medical records were reviewed, when available. A probable measles case was defined as having 3 or more days of rash with fever of 38.3 degrees centigrade or greater, and either cough, coryza, or conjunctivitis. To determine the proportion of cases reported, probable measles cases identified were matched with measles cases reported to the Los Angeles County Department of Health Services. Of the 947 children ages 6 weeks through 59 months included in the surveys, 35 children had experienced an illness episode which met the probable measles case definition. Ten (29 percent) of the 35 probable measles cases were reported to the health department. Hospitals reported 9 (69 percent) of 13 probable measles cases evaluated while private physicians' offices reported 0 (0 percent) of 12 evaluated (Fisher's exact test, P < 0.001), although 5 children were seen by private physicians before rash onset. Reporting was more complete for cases occurring during 1990 and 1991 (33 percent) than from 1987 through 1989 (18 percent). The hospitalization rate for preschool-age children with probable measles cases in the catchment area was estimated to be 8 percent (95 percent confidence interval = 0 to 18 percent). Although measles is a serious communicable disease which is almost completely preventable, cases of it among preschool-age children in this high incidence area were substantially underreported,especially by private physicians. Due to reporting bias, reported measles cases were representative of more severe cases than all the cases that occurred.
Child, Preschool↗