RESUMEN
The magnitude of the public health problem associated with Listeria monocytogenes in the United States has been unknown, and the route of transmission is largely undetermined. Investigations of recent outbreaks, however, have shown that the infection can be foodborne. We estimated the expected frequency of sporadic listeriosis based on hospital discharge data from the Professional Activity Study of the Commission on Professional and Hospital Activities for the years 1980 through 1982. The incidence of listeriosis was 3.6 per million population per year, with an estimated 800 cases occurring in the United States each year. Attack rates were highest in neonates and in those aged 70 years and older (568 and 11 per million population per year, respectively). Overall mortality was 19.1%, with mortality rates increasing with advancing age. We estimated that listeriosis accounts for at least 150 deaths in the United States per year (fetal mortality not included). Throughout the nation, no marked regional differences in the incidence of the disease were apparent. We were able to identify three time-space clusters, which suggests the possibility that a portion of sporadic cases may, in fact, be previously unrecognized common-source clusters.
Asunto(s)
Listeriosis/epidemiología , Meningitis por Listeria/epidemiología , Femenino , Humanos , Listeriosis/transmisión , Masculino , Agrupamiento Espacio-Temporal , Estados UnidosRESUMEN
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.
Asunto(s)
Brotes de Enfermedades/epidemiología , Enfermedad de los Legionarios/epidemiología , Viaje , Brotes de Enfermedades/diagnóstico , Femenino , Humanos , Legionella/aislamiento & purificación , Enfermedad de los Legionarios/diagnóstico , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Estaciones del Año , Pruebas Serológicas , Encuestas y Cuestionarios , Islas Virgenes de los Estados UnidosRESUMEN
An outbreak of meningococcal disease among children on a school bus offered the opportunity to study a proposed association between this infection and preceding influenza infection. Five students who rode the bus became ill with invasive group C meningococcus. Transmission was limited to the bus; there was no evidence for school transmission. All five students reported influenza-like symptoms within several weeks before the development of meningococcal disease. School absenteeism, principally due to upper respiratory tract illness, was higher during the 3 weeks before the outbreak of meningococcal disease than during any period in the preceding 3 1/2 years, suggesting an unusually severe outbreak of respiratory illness. A case-control study comparing students with and without influenza symptoms revealed that the outbreak of respiratory disease was due to B/Ann Arbor/1/86 influenza (geometric mean titers, 86 for 80 patients and 33 for 47 controls [P = .0007]). These data add to the evidence suggesting that influenza respiratory infection predisposes to meningococcal disease.
Asunto(s)
Brotes de Enfermedades , Gripe Humana/epidemiología , Infecciones Meningocócicas/epidemiología , Transportes , Absentismo , Adolescente , Estudios de Casos y Controles , Niño , Humanos , Incidencia , Infecciones Meningocócicas/etiología , Infecciones Meningocócicas/transmisión , Factores de Riesgo , Virginia/epidemiologíaRESUMEN
Fatal toxic shock syndrome developed in a previously healthy 19-year-old man following arthroscopy. The fulminant presentation led to an initial diagnosis of pulmonary embolus. Toxic shock syndrome must now be considered in the differential diagnosis of cardiovascular catastrophes.
Asunto(s)
Artroscopía/efectos adversos , Infección Hospitalaria , Choque Séptico/etiología , Infecciones Estafilocócicas/etiología , Enfermedad Aguda , Adulto , Errores Diagnósticos , Humanos , Masculino , Embolia Pulmonar/diagnóstico , Choque Séptico/diagnóstico , Choque Séptico/mortalidad , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/mortalidad , Staphylococcus aureus/aislamiento & purificaciónRESUMEN
During a five-week period in 1981, six cases of legionellosis due to Legionella pneumophila serogroup 1 were recognized in a hospital in Paris, France. Four cases were clearly nosocomial in origin. There was a direct association between development of disease and exposure to potable hot water (p = 0.003). The entire hot water system was contaminated with L. pneumophila serogroup 1; monoclonal antibody testing demonstrated that the case isolate and the potable water isolates belonged to the same subgroup. Although serogroup 1 was isolated from both the cooling tower and its drift, the cooling tower isolate was antigenically distant from the case isolate. In other nosocomial outbreaks of legionellosis, multiple sources have been found within the hospital environment, but an epidemiologic association of disease with potable water had not been shown. The significant association of cases with exposure to the potable hot water supply, and the identification of case and potable water isolates of the same subtype, suggest that the potable hot water was responsible for transmission of disease in this outbreak.
Asunto(s)
Infección Hospitalaria/transmisión , Enfermedad de los Legionarios/transmisión , Microbiología del Agua , Abastecimiento de Agua , Adulto , Anciano , Aire Acondicionado/instrumentación , Infección Hospitalaria/microbiología , Microbiología Ambiental , Métodos Epidemiológicos , Femenino , Hospitales de Enseñanza , Humanos , Legionella/aislamiento & purificación , Enfermedad de los Legionarios/microbiología , Masculino , Persona de Mediana Edad , ParisRESUMEN
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.
Asunto(s)
Infecciones por Haemophilus/prevención & control , Trastornos de la Pigmentación/inducido químicamente , Rifampin/efectos adversos , Enfermedades de la Piel/inducido químicamente , Enfermedad Aguda , Guarderías Infantiles , Preescolar , Edema/inducido químicamente , Femenino , Haemophilus influenzae , Humanos , Lactante , Masculino , Errores de Medicación , Rifampin/administración & dosificación , Dermatosis del Cuero Cabelludo/inducido químicamente , Vómitos/inducido químicamenteRESUMEN
The Haemophilus influenzae type b polysaccharide vaccine was licensed for use in the United States in April 1985. Postlicensure case-control efficacy studies have yielded markedly different estimates of efficacy, leading to contradictory recommendations to practicing physicians. To obtain additional information about the efficacy of the vaccine, we studied cases of invasive Haemophilus influenzae type b disease ascertained through active surveillance in areas with a total population of 34 million. We enrolled children 24 to 59 months of age who did not attend day-care centers. (Data from our day-care study have been published elsewhere.) For each case child, as many as three 24- to 59-month-old control children were chosen from a roster of acquaintances supplied by the child's parent. Conditional logistic regression was used, and vaccine efficacy was estimated to be 62% (95% confidence interval = 0%, 85%), which did not change significantly after adjusting for age and parental smoking, variables that were significantly different for case and control children. Results of this study support our previous finding of a positive protective efficacy, albeit lower than the efficacy of 90% found in children 18 to 71 months of age in the Finnish prelicensure trial.
Asunto(s)
Vacunas Bacterianas/uso terapéutico , Vacunas contra Haemophilus , Polisacáridos Bacterianos , Cápsulas Bacterianas , Preescolar , Femenino , Infecciones por Haemophilus/epidemiología , Haemophilus influenzae/aislamiento & purificación , Humanos , Masculino , Estados UnidosRESUMEN
Risk factors for acute upper respiratory tract disease in childhood were evaluated in a population-based sample of the Atlanta metropolitan area. Mothers from 449 households containing 575 children less than 5 years of age were selected by random-digit dialing and questioned about upper respiratory tract infection and ear infection occurring in their children during the preceding 2 weeks. Household demographic and socioeconomic characteristics, maternal smoking history and child day-care attendance and breast-feeding information were also obtained. For children less than 5 years of age, the reported incidence of upper respiratory tract infection was 24%, and of ear infection, 6%. Controlling for the other variables measured, day-care attendance was associated with a significantly increased risk of both illnesses. For upper respiratory tract infection, increased risk was present for all children attending day care (P = .02, odds ratio = 1.6), whereas for ear infection, risk could be demonstrated only for full-time attendees (P = .005, odds ratio = 3.8). Maternal smoking was a second independent risk factor for a child's having upper respiratory tract infection (odds ratio = 1.7, P = .01). Thirty-one percent of all upper respiratory tract infection among day-care attendees and 66% of all ear infections among full-time day-care attendees were attributable to day-care attendance. Given the proportion of children in day care, 9% to 14% of the total burden of upper respiratory tract disease in this population was day care related.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Guarderías Infantiles , Infecciones del Sistema Respiratorio/epidemiología , Preescolar , Georgia , Humanos , Conducta Materna , Otitis Media/epidemiología , Otitis Media/transmisión , Infecciones del Sistema Respiratorio/transmisión , Riesgo , FumarRESUMEN
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.
Asunto(s)
Acampada , Brotes de Enfermedades/epidemiología , Neumonía por Mycoplasma/epidemiología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Mycoplasma pneumoniae/aislamiento & purificación , Neumonía por Mycoplasma/microbiología , WisconsinRESUMEN
In June, 1989, an outbreak of nosocomial listeriosis occurred in Costa Rica. Listeria monocytogenes was isolated from 9 ill infants 4 to 8 days old who were born after the delivery of an infant with early onset listeriosis. One nosocomial infection was fatal, 2 required mechanical ventilation and 1 resulted in hemiparesis. A higher proportion of cases than other infants born during the outbreak were delivered by cesarean section (55% vs. 24%, P = 0.04). Compared with the mothers of 36 random controls, case mothers were more often primiparous (odds ratio, 6.2, P = 0.03) or received general anesthesia before delivery (odds ratio, 4.4, P = 0.09). All infants were bathed with mineral oil from a multidose container. Culture of the oil by cold enrichment grew L. monocytogenes 4b with the same electrophoretic enzyme type as the outbreak strain. We hypothesize that aspiration of contaminated oil may have resulted in systemic listeriosis. General anesthesia may have increased the risk of aspiration. Lung tissue from the infant who died showed lipid-laden macrophages consistent with oil aspiration and had evidence of L. monocytogenes DNA detected by polymerase chain reaction. This is the first nosocomial outbreak of listeriosis in which a common source suggested epidemiologically was microbiologically confirmed. The high attack rate (greater than 200 times the United States rate of perinatal listeriosis) emphasizes the susceptibility of healthy neonates to L. monocytogenes. The results of our study led to the discontinuation of the use of mineral oil for bathing neonates in Costa Rica.
Asunto(s)
Infección Hospitalaria/etiología , Brotes de Enfermedades , Listeriosis/etiología , Aceite Mineral/efectos adversos , Estudios de Casos y Controles , Costa Rica/epidemiología , Recolección de Datos , Contaminación de Medicamentos , Femenino , Humanos , Recién Nacido , Listeriosis/epidemiología , MasculinoRESUMEN
During January and August, 1990, 23 cases of early onset Group B Streptococcus (GBS) disease occurred in a Kansas City, MO, hospital with an attack rate of 14/1000 live births, compared with an annual rate of 1.2 cases/1000 live births for 1988 through 1989. Case infants were compared with controls matched by birth weight, race, maternal age and day of delivery and to a second group of infants of mothers colonized with GBS to identify risk factors and consider intervention strategies during the outbreak. The presence of multiple serotypes among the invasive strains suggested that the outbreak was not caused by a common source. Case mothers were more likely than control mothers to have chorioamnionitis, intrapartum fever or rupture of membranes > 12 hours, and premature case infants were more likely to have a history of rupture of membranes before onset of labor. Multiparous mothers of case infants were more likely to have a history of spontaneous abortion (odds ratio, 6.7; 95% confidence interval, 1.0 to 45.9). No single factor could explain the increase in GBS disease. If intrapartum antibiotic prophylaxis had been used for selected GBS carriers based on presence of either rupture of membranes > 12 hours, intrapartum maternal fever or preterm labor, 7.4% of all deliveries would have received antibiotics and 73% of cases could potentially have been prevented. We conclude that identification of colonized mothers with perinatal risk factors and use of intrapartum antibiotics could be expected to prevent substantial disease during an outbreak of early onset GBS disease.
Asunto(s)
Infección Hospitalaria/epidemiología , Infecciones Estreptocócicas/epidemiología , Streptococcus agalactiae , Estudios de Casos y Controles , Infección Hospitalaria/microbiología , Brotes de Enfermedades , Femenino , Humanos , Recién Nacido , Masculino , Servicio de Ginecología y Obstetricia en Hospital/estadística & datos numéricos , Factores de Riesgo , Infecciones Estreptocócicas/microbiologíaRESUMEN
Persistent conjunctival carriage of the Haemophilus influenzae biogroup aegyptius (Hae) strain (BPF clone) responsible for Brazilian purpuric fever (BPF) has been documented. Topical chloramphenicol is routinely used to treat conjunctivitis in areas affected by BPF in Brazil. Although the BPF clone is susceptible to chloramphenicol, we observed a number of children treated with topical chloramphenicol for conjunctivitis who still developed BPF. During an investigation of an outbreak of BPF in Mato Grosso State, Brazil, we compared oral rifampin (20 mg/kg/day for 4 days) with topical chloramphenicol for eradication of conjunctival carriage of H. influenzae biogroup aegyptius among children with presumed BPF clone conjunctivitis. Conjunctival samples were taken for culture on the day treatment was initiated and a mean of 8 and 21 days later. At 8 days the eradication rates for oral rifampin and topical chloramphenicol were 100 and 44%, respectively (P = 0.003); at 21 days they were 100 and 50% (P = 0.01). Oral rifampin was more effective than topical chloramphenicol for eradication of the BPF clone and may be useful in prevention of BPF.
Asunto(s)
Cloranfenicol/uso terapéutico , Conjuntivitis/microbiología , Infecciones por Haemophilus/prevención & control , Haemophilus influenzae , Rifampin/uso terapéutico , Administración Oral , Administración Tópica , Brasil , Portador Sano , Niño , Preescolar , Cloranfenicol/administración & dosificación , Conjuntivitis/prevención & control , Femenino , Infecciones por Haemophilus/microbiología , Humanos , Lactante , Masculino , Orofaringe/microbiología , Púrpura/microbiología , Púrpura/prevención & control , Rifampin/administración & dosificación , Especificidad de la EspecieRESUMEN
Portions of sub-Saharan Africa are subject to major epidemics of meningococcal meningitis that require early detection and rapid control. We evaluated the usefulness of weekly meningitis rates derived from active surveillance data in Burkina Faso for detecting a meningitis epidemic. By analysing the rates of disease in 40 x 40km2 areas within a study region of Burkina Faso, we found that a threshold of 15 cases/100,000/week averaged over 2 weeks was 72-93% sensitive and 92-100% specific in detecting epidemics exceeding 100 cases/100,000/year. During epidemic periods, the positive predictive value of this threshold approached 100% for detecting local epidemics. Additionally, meningitis incidence was proportional to village size, with villages greater than 8000 having the highest disease rates during a major group A meningococcal epidemic in 1983-1984. Despite the rudimentary nature of surveillance data available in many developing countries, these data can be used to detect the early emergence of meningitis epidemics. Additional studies are needed to determine the relevance of this approach for detecting epidemics.
Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Meningitis Meningocócica/epidemiología , Burkina Faso/epidemiología , Humanos , Incidencia , Meningitis Meningocócica/prevención & control , Densidad de Población , Vigilancia de la Población , Estudios Retrospectivos , VacunaciónRESUMEN
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.
Asunto(s)
Demografía , Enfermedad de Lyme/epidemiología , Humanos , Vigilancia de la Población , Estados UnidosRESUMEN
The current epidemic of violence in America threatens not only our physical health but also the integrity of basic social institutions such as the family, the communities in which we live, and our health care system. Public health brings a new vision of how Americans can work together to prevent violence. This new vision places emphasis on preventing violence before it occurs, making science integral to identifying effective policies and programs, and integrating the efforts of diverse scientific disciplines, organizations, and communities. A sustained effort at all levels of society will be required to successfully address this complex and deeply rooted problem.
PIP: Violence is a major contribution to premature death, disability, and injury. In America, there is an epidemic of violence, which threatens not only the physical health, but also the integrity of basic social institutions such as the family, the communities, and the health care system of the public. In this paper, the new vision for violence prevention embodied in the public health approach is discussed. It shifts the focus of the society in the way violence is addressed, from reacting to the problem to changing the social, behavioral, and environmental factors that cause violence. The emphasis is on preventing violence before it occurs, making science integral in identifying effective policies and programs, and integrating the efforts of diverse scientific disciplines, organizations, and communities. A sustained and coordinated effort to prevent violence will be necessary at all levels of society to address this complex and deeply rooted problem.
Asunto(s)
Política de Salud , Salud Pública , Violencia/prevención & control , Adolescente , Adulto , Niño , Participación de la Comunidad , Femenino , Prioridades en Salud , Homicidio/prevención & control , Homicidio/estadística & datos numéricos , Humanos , Lactante , Masculino , Delitos Sexuales/prevención & control , Delitos Sexuales/estadística & datos numéricos , Estados Unidos , Violencia/estadística & datos numéricosRESUMEN
In 1993 a placebo-controlled field trial of a Haemophilus influenzae type b (Hib) conjugate vaccine was started in The Gambia. At that time Hib conjugate vaccines had been shown to be efficacious in Europe and North America for the prevention of Hib meningitis. However doubts remained about their value in developing countries, where the epidemiology of Hib disease is quite different and the most important manifestation of Hib disease is pneumonia. The ethical issues facing the investigators before and during the trial are outlined in this paper, along with the views of the different groups involved in the trial. The trial demonstrated the efficacy of the vaccine in this setting and revealed the proportion of childhood pneumonia that is likely due to Hib, which was much higher than had previously been estimated. Since the completion of the trial Hib vaccines are now recommended for use in developing countries by the World Health Organization, largely based on the results of this trial. After a delay of 17 months following the completion of the trial, national Hib vaccination was started in The Gambia in 1997 using vaccine provided by a donation from industry.
Asunto(s)
Ética Médica , Infecciones por Haemophilus/prevención & control , Vacunas contra Haemophilus , Neumonía Bacteriana/prevención & control , Gambia , Infecciones por Haemophilus/microbiología , Haemophilus influenzae tipo b , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento , Vacunas ConjugadasRESUMEN
In 1986, an outbreak of Moraxella follicular conjunctivitis occurred in girls attending a Navajo boarding school in New Mexico. We diagnosed 19 cases of culture-proven, and 21 of clinical conjunctivitis based on isolation of Moraxella from conjunctival cultures and the occurrence of symptoms significantly associated with positive culture. Sharing eye makeup was significantly associated with Moraxella-positive conjunctivitis (odds ratio [OR] = 7.2, P = .004) and showed a trend toward significance in those with clinical conjunctivitis (OR = 2.9, P = .09). Eyeliner and eye shadow were implicated (OR = 4.1, P less than .05). We cultured samples of 13 students' makeup; one third of the eyeliners were positive for Moraxella. Nasal carriage of Moraxella was found in 35 (44%) of the 79 female boarders and in 20 (21%) of 97 Navajo patients at two nearby clinics. In a prospective evaluation of the effect of patient education and rifampin therapy on the occurrence of conjunctivitis during an 11-month follow-up period, both types of intervention were successful in significantly reducing the rate of conjunctivitis when compared with that in a control group.
Asunto(s)
Infecciones Bacterianas/epidemiología , Conjuntivitis Bacteriana/epidemiología , Brotes de Enfermedades , Indígenas Norteamericanos , Adolescente , Infecciones Bacterianas/prevención & control , Conjuntiva/microbiología , Conjuntivitis Bacteriana/prevención & control , Cosméticos/efectos adversos , Brotes de Enfermedades/prevención & control , Femenino , Humanos , Masculino , Moraxella/aislamiento & purificación , New Mexico , Nariz/microbiología , Educación del Paciente como Asunto , Estudios Prospectivos , Rifampin/uso terapéutico , Factores de RiesgoRESUMEN
The complete pathogenesis of toxic shock syndrome (TSS) has yet to be elucidated. Unmasking the complex interactions among bacterial products, host factors, and possibly tampon components requires a suitable in vivo model. For this purpose, subcutaneous chambers implanted in rabbits were inoculated with Staphylococcus aureus isolated from patients with TSS. Infected rabbits developed illness characterised by multisystem involvement that included periportal inflammation of the liver, erythrophagocytosis in the spleen and lymph nodes as well as extreme vascular dilatation and epithelial lesions similar to those described in patients with TSS. Concentrations of serum creatinine (P less than 0.03) and triglycerides (P less than 0.04) were significantly raised in rabbits infected with TSS strains compared with rabbits infected with non-TSS strains of S. aureus. Both TSS and non-TSS strains of S. aureus produced fever and diarrhoea, but TSS strains were significantly (P less than 0.05) more lethal and more likely to produce respiratory distress and lowered blood pressure. This model may help to prove or disprove proposed mechanisms for the development of TSS.
Asunto(s)
Choque Séptico/patología , Infecciones Estafilocócicas/patología , Animales , Dermatitis Exfoliativa/etiología , Diarrea/etiología , Femenino , Fiebre/etiología , Humanos , Hígado/patología , Ganglios Linfáticos/patología , Masculino , Conejos , Choque Séptico/complicaciones , Bazo/patología , Infecciones Estafilocócicas/complicacionesRESUMEN
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.
Asunto(s)
Brotes de Enfermedades/epidemiología , Contaminación de Alimentos , Faringitis/epidemiología , Métodos Epidemiológicos , Microbiología de Alimentos , Humanos , Faringitis/etiología , Puerto Rico , Streptococcus pyogenes/aislamiento & purificaciónRESUMEN
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.