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Outbreaks of legionnaires' disease (LD) in tourists visiting Italian and Spanish resorts have been recently reported. An unusual number of reports of LD in tourists visiting the US Virgin Islands prompted an investigation of risk factors for development of LD in this area. Twenty-seven cases of LD were identified between 1979 and 1982 through press reports, personal communication, the national LD surveillance system, a review of hospital records, and a mail survey. Twenty-four of 27 persons with the disease had visited St Croix and 12 of them had stayed at a single hotel in 1981. Available evidence suggested that infection was due to Legionella pneumophila serogroup 1; L pneumophila serogroups 1 and 3 and several new Legionella species were isolated from the potable water system at the hotel. Following hyperchlorination of the potable water system, no further cases of LD in hotel visitors have been identified to date.

In 1982, national surveillance for Lyme disease was established by the Centers for Disease Control to monitor trends and determine endemic geographic areas. Initially, the endemic areas corresponded to the known distribution of Ixodes dammini, a five-state area of the northeastern seaboard (New York, New Jersey, Connecticut, Rhode Island, and Massachusetts) and Wisconsin and Minnesota. Increasing numbers of cases have been reported outside these areas, however, 86% of the provisional 5731 cases reported to CDC were acquired in these seven states. The number of reported cases increased from 491 in 1982 to approximately 1500 per year in 1984-1986, making Lyme disease the most commonly reported tick-borne illness in the United States. The apparently widening distribution of Lyme disease indicates that physicians in all regions of the country should be familiar with its signs and symptoms. Investigations of the vector in areas endemic for Lyme disease where Ixodes ticks are not found are warranted.

The aim of a study of all groups L-T streptococci isolated at the Massachusetts General Hospital during a 10-year period (1964-1974) was to ascertain the clinical significance of the less frequently occurring serological groups of streptococci. No organisms of groups P,R,S, or T were found during this time. The case records of 109 clinical isolates of alpha-reacting streptococci of Lancefield groups L,M,N, and O from blood and cerebrospinal fluid cultures were reviewed. There were six cases of endocarditis and one case of infected sternotomy uound with septicemia due to these streptococci. The two cases of endocarditis due to group O streptococci represent the first cases described with endocarditis caused by this group of organisms. Virtually all of the isolates of groups L,M,N, and O streptococci were susceptible to penicillin. Seventy-four percent of the isolates were judged not responsible for clinical disease. The importance of avoiding inappropriate therapy makes it necessary to realize that these organisms are potential "contaminants" of cultures of blood and cerebrospinal fluid.

The pathogenic basis for the association of tampons with toxic shock syndrome (TSS) has not been explained adequately. Absorbency and chemical composition of tampons are related, and no prior study has had a sufficient number of cases to evaluate these independently as risk factors for disease. We compared national TSS passive surveillance data on the 285 tampon-associated menstrual cases of TSS reported from 1983 to 1984 with data on age- and year-matched controls from national surveys of tampon usage. Users of all brands of tampons had elevated risks when compared with non-tampon users (odds ratio, 32.8; 95% confidence interval, 15.5, 69.6). Regardless of the chemical composition of the tampon, increasing absorbency increased the odds ratio for TSS. Chemical composition also influenced odds ratios. Polyacrylate-containing tampons had odds ratios that were elevated but, once controlled for absorbency, that were lower than the odds ratios for cotton, rayon, and cotton/rayon tampons. The strong association of absorbency with risk of illness would suggest that as a public health measure the use of a low-absorbency tampon is likely to reduce the risk of TSS in the user.

One hundred and thirty cases of toxic shock syndrome not associated with menstruation have been reported to the Centers for Disease Control, including 57 with onset in 1981 (12% of reported cases in 1981). These cases show that the syndrome occurs in a wide range of clinical settings and is associated with Staphylococcus aureus infections at a variety of sites: focal cutaneous and subcutaneous lesions, surgical-wound infections, postpartum infections, adenitis, bursitis, deep abscesses, and "primary" bacteremia. Although the clinical characteristics of nonmenstrual toxic shock syndrome are identical to those for menstrual toxic shock syndrome, the epidemiologic and demographic features are different. Of particular interest is the contrast in the racial distribution of the menstrual and nonmenstrual cases. Toxic shock syndrome can occur in persons of any age, race, or sex and must be considered in the differential diagnosis for any patient with a compatible illness.

A vesicular, peeling rash characteristic of a phytophototoxic dermatitis developed on the hands and arms of 30 of 127 grocery workers. The rash subsequently healed with residual hyperpigmentation. Produce workers had the highest attack rate, 100% (8 of 8, p less than 0.0001). Although contact with celery had the highest relative risk for disease (relative risk, 6.3; 95% confidence interval, 2.6, 19.2) and the strongest dose-response effect, an association with celery alone could not be shown because workers were also exposed to other produce. However, anecdotal evidence also suggested that celery might be involved. The disease-resistant, high-quality brand of celery carried by these stores had higher levels of furanocoumarins, potent photosensitizers and a known cause of phytophotodermatitis, than other brands (p = 0.01). A randomly selected nationwide sample of stores in this chain showed dermatitis in 13 of 17 states and 26% of produce workers surveyed. Plant breeding to produce a more disease-resistant celery stock may lead to increased levels of endogenous furanocoumarins, resulting in phytophotodermatitis in grocery workers.

In the period April to October, 1977, an epidemic of pertussis in the outpatient population of a large metropolitan hospital involved 115 cases that were diagnosed by culture or direct fluorescent antibody tests. A study of secondary cases in household contacts showed attack rates of 81% in children under one year of age; attack rates decreased with increasing age to 8% in persons over 20 years of age. Vaccine efficacy was estimated to be 63%. There was no evidence of decreased efficacy with increasing time after vaccination. Fourteen asymptomatic FA-positive individuals were identified; four of these were also culture positive. Four were adults and ten were children. Nine of the ten children had received three or more vaccinations, compared to only 29 of 78 symptomatic children (P = 0.002).

A blind reading of direct immunofluorescent staining of sputum smears was positive in five of 21 patients with Legionnaires' disease and none of 47 control patients. Positive slides showed from eight organisms per smear (one slide) to 20 to 100 organisms per oil-immersion (magnification, 100) field (three slides). Two of the positive specimens were obtained through an endotracheal tube, one at bronchoscopy, and the other positive slides were from expectorated specimens. In addition, two open-lung biopsies and a bronchial lavage sediment from three confirmed cases of Legionnaires' disease were positive by direct immunofluorescent staining for Legionnaires' disease bacterium.

For assessment of current risk factors for developing toxic shock syndrome (TSS) during menstruation, a case-control study was performed. Cases with onset between 1 January 1986 and 30 June 1987 were ascertained in six study areas with active surveillance for TSS. Age-matched controls were selected from among each patient's friends and women with the same telephone exchange. Of 118 eligible patients, 108 were enrolled, as were 185 "friend controls" and 187 telephone exchange-matched controls. Tampon use was a risk factor for developing TSS during menstruation (odds ratio = 29; 95% confidence interval = 7-120), and risk increased with increasing tampon absorbency (odds ratio = 1.34 per gram increase in absorbency; 95% confidence interval = 1.2-1.6). The role of tampon chemical composition could not be assessed because the number of cases was inadequate. Neither use of birth control pills for contraception nor use of medications for premenstrual or menstrual symptoms protected against or was a risk factor for the development of menstrual TSS.

In March-April 1985, toxic shock syndrome (TSS) developed in three male military trainees at one base secondary to infected blisters acquired while marching during basic combat training. One trainee died. Staphylococcus aureus was isolated from the blisters in all three patients, and the two strains available for testing both produced toxic shock syndrome toxin-1 (TSST-1). A culture survey identified carriage of S. aureus in 44% (145/333) of the trainees; carriage rates did not differ between the company with two ill trainees and a control company. Carriage was more frequent in the nose than foot (41% versus 9%, p less than 0.0001). White trainees were more likely to carry S. aureus than black trainees (47% versus 28%, p = 0.013), although the same proportion of strains was positive for TSST-1 in both races. The two strains obtained from the patients had similar but not identical phage typing patterns, but had identical antibiograms, and neither strain carried any plasmids. Based upon phage typing of the TSST-1 positive S. aureus strains isolated in the study, widespread carriage of the case strain(s) in other trainees was not found nor was clustering noted by barrack room. It is possible that differences in carriage rates may partially explain the low rate of TSS in blacks.

Sets of sera (444) submitted for diagnostic testing for legionellosis were tested against 29 indirect immunofluorescence assay (IFA) antigens prepared from the characterized Legionella species and Legionella-like organisms to determine the prevalence of antibodies to Legionella organisms. Reciprocal titers of 15% of the serum sets rose fourfold or more to greater than or equal to 128 (indicating seroconversion) against one or more Legionella antigens. The specificity of the test was 96% when evaluated in patients with pneumonia due to non-Legionella organisms. Antibodies were of the IgG, IgM, and (infrequently) IgA classes and were either specific for a single species (as defined by a difference in titer of fourfold or more) or reacted with common Legionella antigens (30 [45%] vs. 36 [55%] of 66 seroconversions, respectively). No single antigen detected half of the positive sera. Elevated IFA titers (of greater than or equal to 256) against single or multiple Legionella antigens occurred in 12% of 184 normal control sera. Therefore, only seroconversions to titers of greater than or equal to 128 should be considered indicative of recent Legionella infection.

Following a private party in Río Piedras, PR, 23 (56 percent) of those who attended developed an illness characterized by pharyngitis, myalgia, fatigue, headache, and fever. Consumption of carrucho (conch) salad was significantly associated with illness (P = 0.013, Fisher's exact test). Group A beta-hemolytic streptococci (M nontypable T12, serum opacity factor positive) were isolated both from throat cultures in 11 of 47 persons who attended the party and from the implicated food. The original source of contamination of the conch salad was not identified. Because complications may still occur from such infections and only a small percentage of persons with sore throats seek medical attention and ultimately receive treatment for their illnesses, it is important to recognize these outbreaks.

In 1986-87 the Centers for Disease Control conducted an active population-based survey of Listeria monocytogenes infections in six regions of the United States. Listeriosis was reported in 154 patients: one-third of cases were perinatal and the remaining two-thirds occurred in the elderly and immunosuppressed. 28% of cases were fatal. 82 cases and 239 controls matched for age and underlying disease were enrolled in a study of risk factors for listeriosis. Cases were significantly more likely than controls to have eaten uncooked hot dogs or undercooked chicken, with 20% of the overall risk of listeriosis attributable to consumption of these foods. No other risk factors were identified.

The occurrence, clinical, and epidemiologic characteristics of fatal nosocomial Legionnaires' disease were ascertained by examining a sample of autopsy specimens submitted by hospitals participating in the National Nosocomial Infections Study. Sections of lung tissue from 263 patients were submitted by 40 hospitals in 24 states. Legionnaires' disease was identified in 10 patients (3.8%) from six hospitals in five states. The clinical and epidemiologic characteristics of sporadic fatal nosocomial Legionnaires' disease were similar to those from cases that occurred during epidemics of Legionnaires' diseases. A case-control study showed that cases of Legionnaires' disease were associated with an increased occurrence of Legionnaires' disease during the period June through November, temperatures greater than 39.2 degrees C, and administration of corticosteroids before onset of pneumonia. Legionnaires' disease can occur as a fatal nosocomial pneumonia and has clinical and epidemiologic features that may be helpful in differentiating it from nosocomial pneumonia of other causes.

Sequential case-control studies were used to monitor changes in the clinical protection induced by group A meningococcal polysaccharide vaccine over a 3-year period. Overall, vaccine efficacy declined from 87% 1 year after vaccination to 70% and 54% at 2 and 3 years, respectively. When stratified by age at time of vaccination the data showed that, although vaccine efficacy remained high in children greater than or equal to 4 years of age (vaccine efficacy 85%, 74%, and 67% at 1, 2, and 3 years after vaccination, respectively), it declined dramatically in those less than 4 years of age at time of vaccination (vaccine efficacy 100%, 52%, and 8%, respectively, at 1, 2, and 3 years after vaccination). Thus, a single dose of group A meningococcal vaccine does not yield lasting clinical protection in children less than 4 years of age.

The ubiquity of Legionella pneumophila in the environment creates special problems for identifying the source of either outbreaks or sporadic cases due to this organism. Efforts must be made to associate a specific hypothesized source with the occurrence of disease through appropriate epidemiologic studies. Well documented sources of outbreaks include contaminated heat rejection devices, industrial aerosols, and recreational whirlpools. The presence of L. pneumophila in potable water supplies has been associated with the disease in several settings. The precise mechanism of aerosol generation and transmission from potable water remains to be defined.

The availability of new data regarding the risk of invasive Haemophilus influenzae type b (Hib) among day care attendees allows the formulation of a practical public health approach to this problem. It is now clear that day care attendees are at significantly increased risk for development of primary invasive Hib disease. While the risk of secondary Hib disease for most is low, risk is substantially increased when young day care attendees are exposed to a primary case to a degree analogous to that of household contacts. Because risk for primary Hib disease is increased among day care attendees, immunization of these children with Hib polysaccharide vaccine is of the highest priority and may be appropriate for children as young as 18 months of age. In light of new data documenting the efficacy of rifampin in prevention of secondary disease, the use of this medication is indicated when unvaccinated day care attendees younger than two years old have had significant contact with a primary case.

Active surveillance for toxic shock syndrome (TSS) was established in 1986 in Los Angeles County and in the states of Missouri, New Jersey, Oklahoma, Tennessee, and Washington. Case reports were solicited through biweekly contact with all acute-care hospitals. One hundred sixteen definite and 63 probable cases were reported; 85% of the cases occurred in female patients and 15% in male patients. Among cases in females, 83 (55%) were menstrual; the mean age of the patients with menstrual cases was 23 years (range, 12-46 years). The overall incidence of TSS was 0.53/100,000. The cumulative incidence varied significantly by region, ranging from 1.23/100,000 in Oklahoma to 0.22/100,000 in New Jersey (P = .0001); the incidence in all other areas ranged from 0.39/100,000 to 0.70/100,000. The incidence of menstrual TSS was 1.05/100,000 women 15-44 years of age and peaked in women between the ages of 15 and 19 years at 1.52/100,000. The incidence was higher in whites than in nonwhites for both menstrual TSS (1.21/100,000 vs. 0.34/100,000, P = .002) and nonmenstrual TSS (0.30/100,000 vs. 0.14/100,000, P = .031). Our data indicate that TSS continues to be a cause of morbidity. Although there is underreporting in national passive surveillance, the proportion of menstrual cases reported through active surveillance was similar to that reported to the passive system in 1986.

Lyme disease is an increasingly recognized tick-borne illness caused by a spirochete, Borrelia burgdorferi. Because the etiologic agent of Lyme disease is a spirochete, there has been concern about the effect of maternal Lyme disease on pregnancy outcome. We reviewed cases of Lyme disease in pregnant women who were identified before knowledge of the pregnancy outcomes. Nineteen cases were identified with onset between 1976 and 1984. Eight of the women were affected during the first trimester, seven during the second trimester, and two during the third trimester; in two, the trimester of onset was unknown. Thirteen received appropriate antibiotic therapy for Lyme disease. Of the 19 pregnancies, five had adverse outcomes, including syndactyly, cortical blindness, intrauterine fetal death, prematurity, and rash in the newborn. Adverse outcomes occurred in cases with infection during each of the trimesters. Although B burgdorferi could not be implicated directly in any of the adverse outcomes, the frequency of such outcomes warrants further surveillance and studies of pregnant women with Lyme disease.

A total of 281 Staphylococcus aureus strains selected from those submitted to the Centers for Disease Control for phage typing between 1956 and 1982 were tested for the production of toxic-shock-associated protein (TSAP) by isoelectric focusing (IEF) and solid-phase radioimmunoassay. The results suggest that the observed temporal trends in the incidence of toxic-shock syndrome were not primarily due to changes in the distribution of TSAP-positive strains of S. aureus. Overall, 39 (14%) were TSAP positive by both methods. The earliest positive strain was an isolate submitted in 1957. TSAP-positive strains were most prevalent in the group of isolates submitted in 1976 for which 29% reacted, but the percent positive subsequently declined for isolates submitted in later years. TSAP production was more frequent among strains of phage types 29, 29/52, and 52 than among other strains. The use of IEF to identify TSAP detected false-positive proteins. Seven strains were positive by IEF and negative by solid-phase radioimmunoassay, whereas only one was positive by solid-phase radioimmunoassay and negative by IEF.

After a decade-long resurgence, including a large cutaneous diphtheria outbreak in Washington State, the diphtheria incidence rate in the United States reached its lowest recorded level ever in 1980--two patients (0.01 case per million). Mortality paralleled the decline in incidence rate. Only 143 of the 3,141 US counties reported noncutaneous diphtheria patients during 1971-81; most were located in the West. The highest attack rates were experienced by children less than 15 years old (0.8 case per million) and by American Indians (22.6 cases per million). Persons immunized with three or more doses of diphtheria toxoid had a lower death-to-case ratio (1.3 per cent) than totally unimmunized persons (13.4 per cent). The reasons for the dramatic decline in diphtheria incidence rates are unclear, although it has been postulated that the gene for producing diphtheria toxin may be lost from organisms in highly immunized populations. Significant proportions of the adult and elderly populations are susceptible to diphtheria. Continuation of primary immunization with increased emphasis on the routine use of tetanus and diphtheria toxoids (Td) boosters in adults should ensure that diphtheria will remain largely a scourge of the past.

Sera from six outbreaks of legionellosis and four outbreaks of pneumonia of other etiologies were tested with the indirect immunofluorescence assay (IFA) as currently performed. The current IFA is at least as sensitive as the original test in detecting cases of Legionnaires disease (78 to 91%). By using Center for Disease Control criteria for a positive (fourfold increase in titer during convalescence to greater than or equal to 128) or presumptive (single titer greater than or equal to 256) serological test, the specificity exceeded 99%. No cross-reactions against Legionella pneumophila antigens were observed among sera from epidemic cases of Q fever, tularemia, and psittacosis; the only positive L. pneumophila IFA titer among the epidemic Mycoplasma pneumonia sera was reduced to a negative titer with an immunosorbent extracted from Escherichia coli strain O13:K92:H4. The slight increase in specificity (to 100%), however, was offset by a slight decrease in sensitivity. The sensitivity of the IFA was maximal when a conjugate that detected immunoglobulins G, M, and A was used. IFA titers were not significantly altered by replacing the monovalent serogroup 1 antigen with a polyvalent antigen (serogroups 1 through 4) nor by the presence of rheumatoid factor or heat-labile serum factors.

An outbreak of Mycoplasma pneumoniae infection occurred in the summer of 1978 in a boys' camp in northern Wisconsin and affected 139 of 196 persons (71%); 115 (59%) had laboratory evidence of infection. In 77% of the cases, onset of disease occurred within three weeks after arrival at camp, in contrast to the usually indolent spread of the disease. Attack rates decreased with increasing age. The sensitivity of serology for detecting M pneumoniae disease may have been as low as 79%. There was shorter duration of cough in those treated with erythromycin within four days after onset of symptoms.

A cluster of toxic reactions among children inadvertently given excessive doses of rifampin for chemoprophylaxis of invasive Haemophilus influenzae disease in a day-care center was investigated. In all 19 children, who received five times the therapeutic dose of rifampin, dramatic adverse reactions developed. A striking, "glowing" red discoloration of the skin and facial or periorbital edema were found to be the hallmarks of rifampin toxicity. These clinical signs of acute toxicity contrast sharply with the adverse side effects of rifampin reported with therapeutic doses.

We performed a population-based case-control study of risk factors for primary invasive Haemophilus influenzae type b (Hib) disease in metropolitan Atlanta from July 1, 1983, through June 30, 1984. Active surveillance identified 102 cases in children less than 5 years of age, 89 of whom lived in households with telephones. We used random digit dialing to select 530 controls who were postmatched to cases by age. Multivariate analysis showed a significant association between Hib disease and two independent exposure factors, household crowding (odds ratio (OR) 2.7, 95% confidence limits (CL) 1.3 to 5.6) and day-care attendance. For day-care attendance, relative risk was highest in 2- to 5-month-old infants (OR 17.7, 95% CL 5.8 to 54.4) and declined to 9.4 (4.3 to 20.9) at ages 6 to 11 months, 5.0 (2.7 to 9.3) at 12 to 23 months, 2.7 (1.3 to 5.5) at 24 to 35 months, and 1.4 (0.5 to 4.0) in 36- to 59-month-old children. Fifty percent of all invasive Hib disease that occurred during the study period was attributable to exposure to day-care; the attributable risk for household crowding was 18%. Dose-response effects were observed for hours per week of day-care attendance and extent of household crowding. Breast-feeding was protective for infants less than 6 months of age (OR 0.08, 95% CL 0.01 to 0.59). After controlling for socioeconomic and other confounding factors, we could demonstrate no effect of black race on cumulative risk of invasive Hib disease. Our study defines high-risk groups and provides a population-based model of the interrelationship between risk factors associated with invasive Hib disease.

Use of barrier contraceptives has been hypothesized to be a risk factor for nonmenstrual toxic shock syndrome (TSS). This association was evaluated in a case-control study of nonmenstrual TSS; cases were identified through an active surveillance system for TSS during 1986 and 1987. Potential risk factors for nonmenstrual TSS were compared for 28 patients and 100 age-matched controls. Use of barrier contraceptives was associated with a significantly increased risk of nonmenstrual TSS, with matched odds ratios of 10.5 and 11.7 for contraceptive sponge and diaphragm use, respectively. Use of nonbarrier contraceptive methods was unrelated to nonmenstrual TSS. Despite the elevated odds ratio, the incidence of nonmenstrual TSS in barrier contraceptives users and the risk of nonmenstrual TSS attributable to barrier contraceptive use are low. Clinicians and women who use barrier contraceptives should be aware of this rare but potentially fatal complication; however, other considerations, such as efficacy and complications associated with other types of contraception, may be more important in the choice of a contraceptive method.

An outbreak of invasive disease, including pneumococcal bacteremia, meningitis, and pneumonia, involved 17 of 83 (20.5%) chimpanzees at a primate rehabilitation unit. Invasive disease was more common in splenectomized than in nonsplenectomized animals (42.9% vs 18.4%), but the difference was not statistically significant. The outbreak followed closely an outbreak of upper respiratory tract infection (URTI) that occurred with equal frequency in splenectomized and nonsplenectomized chimpanzees. Those with URTI were 5.7 times as likely to develop invasive disease than those without URTI (P less than 0.005). Fourteen of 20 (70%) chimpanzees with recent URTI and serologically examined had a 4-fold or greater rise in titer to parainfluenza type 3 virus. The outbreak of invasive disease occurred despite the fact that most of the chimpanzees had been vaccinated with pneumococcal vaccine. Efficacy of pneumococcal vaccine could not be demonstrated among any segment of the chimpanzee population, and testing of sera from 23 vaccinated chimpanzees against 4 pneumococcal serotypes (3, 6, 8, and 14) failed to show a meaningful immune response. The findings demonstrated that viral URTI can predispose primates to invasive infections and suggested that pneumococcal vaccine is not protective in chimpanzees.

We studied a group of 31 bacterial isolates from clinical specimens, received by the Centers for Disease Control since 1961, which have been denoted thermophilic for their unusual ability to grow at 50 degrees C. Microbiological characteristics were determined for the group, and an assessment of their clinical significance was made based on retrospective chart review. These bacteria are all gram-negative, nonfermentative, nonsporulating rods, most of which grow better at 42 or 50 degrees C than at 35 degrees C. Some of the bacteria could be implicated as the etiological agents for meningitis, endocarditis, and septicemia. Thermophilic bacteria should be considered potential pathogens when isolated from appropriate clinical specimens.

The validity of commercial latex agglutination kits for detection of Haemophilus influenzae type b and Streptococcus pneumoniae antigens in serum and urine specimens was studied. We tested serum and urine specimens from 44 patients with bacteremic pneumonia (23 S. pneumoniae, 13 H. influenzae type b, 11 other) with commercial latex agglutination kits (Directigen, Bactigen) for S. pneumoniae and H. influenzae type b antigens. All specimen samples were randomized and read blindly by two readers. Interreader reproducibility was 100%. The sensitivity and specificity of both kits for H. influenzae type b antigens in serum and urine were greater than 90%. None of the 24 urine samples from S. pneumoniae bacteremic patients were positive by either kit, although 6 ng of type 3 polysaccharide could be detected in spiked urine. Sensitivity for S. pneumoniae antigens in serum was 27% for Directigen and 38% for Bactigen. Specificity for S. pneumoniae antigens in serum was 95% for Directigen and 74% for Bactigen. The results suggest that the kits are useful in diagnosing H. influenzae type b pneumonia. However, the commercially available S. pneumoniae reagents tested appear to have limited utility for diagnosing S. pneumoniae pneumonia because both kits lack sensitivity and Bactigen lacks specificity, as well.

An increasing proportion of reported cases of toxic-shock syndrome (TSS) are not associated with menstruation (13.2% of reported cases with onset in 1981). The 54 cases of TSS not associated with menstruation reported through the U.S.A. national surveillance system between January, 1980, and June, 1981, were either associated with Staphylococcus aureus infections (cutaneous or subcutaneous lesions, infected surgical wounds, bursitis, mastitis, adenitis, lung abscess, or primary bacteraemia) or followed childbirth by vaginal delivery and caesarean section. Patients with TSS not associated with menstruation differed significantly in age and racial distributions from those with menstruation-associated TSS, and 17 of them were male. The clinical features of TSS not associated with menstruation and the characteristics of the S. aureus strains isolated from these patients were similar to those observed in TSS related to menstruation. The median incubation period of the disease in the post-surgical cases was 2 days. TSS can occur in many clinical settings in patients of both sexes and of all ages and racial groups.

We evaluated the clinical characteristics of patients with Francisella philomiragia (formerly Yersinia philomiragia) isolated from normally sterile sites. Isolates from 14 patients were received by the Centers for Disease Control between 1975 and 1987: 9 were from blood; 2 from lung biopsies; and 1 each from pleural, peritoneal, and cerebrospinal fluid. Underlying problems included chronic granulomatous disease in 5 patients, near-drowning in 5, and a myeloproliferative disease in 2. All 13 patients for whom records were available had a febrile syndrome compatible with bacterial infection. Pneumonia and fever-bacteremia were the commonest clinical syndromes reported. In 7 cases, F. philomiragia was the only sterile-site isolate, and the clinical syndrome did not resolve without appropriate antibiotics. Familiarity with this organism is important because of its ability to cause serious disease in chronic granulomatous disease and near-drowning patients. Further study may yield new insights into pathogenic and host defense mechanisms.

In little more than half a century we have come a long way toward the eventual elimination of invasive Hib disease as a major threat to children in the United States. The Haemophilus b polysaccharide vaccine has provided the first tool for large scale public health intervention efforts in specific target groups of children older than 18 months of age who are likely to benefit from immunization. Immunization programs using the currently available vaccine represent an interim measure that is likely to be replaced within the next few years by new programs utilizing an improved vaccine with greater potential for preventing invasive Hib disease in susceptible infants and young children. Prospects appear good that an improved second generation vaccine that will provide protective efficacy in infants during the first year of life will become available in the near future.

Staphylococcus aureus from patients with toxic shock syndrome (TSS) produce TSS toxin 1. We transferred, by a bacteriophage, the ability to produce TSS toxin 1 from a TSS toxin 1-positive to a TSS toxin 1-negative strain of S. aureus. This recombinant strain produced TSS toxin 1 as confirmed by isoelectric focusing, immunodiffusion, radioimmunoassay, and autoradiography. The recombinant produced TSS-like illness in rabbits, and was significantly (P less than 0.001) more lethal than the recipient strain. Both strains produced fever and diarrhea, but, in addition, rabbits challenged with the recombinant also developed lowered blood pressure (P = 0.002), conjunctival hyperemia, erythroderma, and respiratory distress. Histopathological findings in rabbits challenged with the recombinant strain were remarkably similar to those described for humans with TSS, e.g., erythrophagocytosis, liver "triaditis," and vasodilatation. This study demonstrates that this protein may contribute to the pathogenesis of the TSS.

Electrophoretic enzyme typing revealed that a single group A Neisseria meningitidis clonal complex, designated III-1, was responsible for recent epidemics in Nepal, Saudi Arabia, and Chad. Epidemiological investigations and enzyme typing profiles indicated that this clone was brought from South Asia to the Middle East by Muslims making their pilgrimage (haj) to Mecca, Saudi Arabia, in 1987. Pilgrims who became group A carriers introduced this clonal group into sub-Saharan Africa on their return from the haj. The introduction of this clonal group into sub-Saharan Africa may be responsible for the current wave of epidemics affecting the region. Although the findings suggest that clonal virulence is an important factor in the development of epidemics of meningococcal disease, other factors also seem to be necessary for the development of an epidemic.

Hemophilus influenzae type b (HIB) is the leading cause of bacterial meningitis in the United States. Efforts are under way to develop vaccines immunogenic in children younger than 18 months, but clinical efficacy of a previously developed HIB polysaccharide vaccine has already been established in children aged 18 months or older. We developed a cost-effectiveness model to evaluate immunizing US children with this HIB polysaccharide vaccine pending development of a more immunogenic product. The model permitted comparison of the impact of alternative strategies for use of the vaccine, including universal use at 18 or 24 months of age, use of a second dose after primary immunization, and use in high-risk groups such as day-care-center attendees. Universal vaccination at 18 or 24 months of age resulted in similar estimates of disease prevented, as a consequence of the higher expected efficacy and duration of immunity for the vaccine when given at 24 months. Overall, the implementation of routine childhood immunization against HIB at 18 months of age was the most cost-effective strategy. Universal vaccination at 18 months of age combined with a second dose for day-care-center attendees would substantially increase the number of cases prevented, with a minimal increase in costs. Universal vaccination with a two-dose schedule beginning at 18 months of age could prevent the most disease.

Between June 30th and August 30th, 1983, 49 patients in Massachusetts acquired listeriosis. Seven cases occurred in fetuses or infants and 42 in immunosuppressed adults; 14 patients (29 per cent) died. Of 40 Listeria monocytogenes isolates available for testing, 32 were serotype 4b. Two case-control studies, one matching for neighborhood of residence and the other for underlying disease, revealed that the illness was strongly associated with drinking a specific brand of pasteurized whole or 2 per cent milk (odds ratio = 9, P less than 0.01 for the neighborhood-matched study; odds ratio = 11.5, P less than 0.001 for the illness-matched study). The association with milk was further substantiated by four additional analyses that suggested the presence of a dose-response effect, demonstrated a protective effect of skim milk, associated cases with the same product in an independent study in another state, and linked a specific phage type with the disease associated with milk. The milk associated with disease came from a group of farms on which listeriosis in dairy cows was known to have occurred at the time of the outbreak. Multiple serotypes of L. monocytogenes were isolated from raw milk obtained from these farms after the outbreak. At the plant where the milk was processed, inspections revealed no evidence of improper pasteurization. These results support the hypothesis that human listeriosis can be a foodborne disease and raise questions about the ability of pasteurization to eradicate a large inoculum of L. monocytogenes from contaminated raw milk.