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Coccidioidomycosis is a fungal infection caused by Coccidioides immitis or Coccidioides posadasii. These fungi are known to thrive in desert climate. Fungi produce infectious arthroconidia in soil, they are aerosolized in the air and when inhaled by humans, usually cause infections such as pneumonia. The first cases of coccidioidomycosis in Brazil were reported in 1978. Since then, there have been other reports mainly from desert regions of Northeastern Brazil. The present report describes three cases of coccidioidomycosis on male farmers from Serra Talhada county, Pernambuco State, who developed pneumonia and were subsequently diagnosed with pulmonary coccidioidomycosis. These three farmers were successfully treated with oral fluconazole. They reported having hunted armadillos in a rural and arid area of Pernambuco State. Armadillos are known to be carriers of Coccidioides. This is the first report of infection caused by Coccidioides in Pernambuco State, Brazil.

Coccidioidomycosis is a common, environmentally acquired, pulmonary fungal infection in arid and semi-arid regions of the West, especially Arizona and California. The infection is frequently associated with striking cutaneous manifestations. Reactive, immunologically mediated eruptions include erythema nodosum, a generalized exanthem, Sweet syndrome, and reactive granulomatous dermatitis. Less commonly, the skin can harbor the actual organisms as a result of dissemination from the lungs. Dermatologists may play a key role in the recognition of coccidioidomycosis

Background: Outbreaks of histoplasmosis have been increasingly reported in association with travel to endemic areas. Multiple outbreaks have been reported following travel to the Americas, but reports of pulmonary histoplasmosis in short-term immunocompetent travelers to Africa are rare., Methods: A biology student was referred to our unit with suspected pulmonary histoplasmosis following her return from a field trip in the Ugandan rainforest. The patient informed us that several of her multinational student colleagues on the same expedition had developed a similar illness. Using an alert in ProMED-mail and a questionnaire forwarded to each of the symptomatic students, we accumulated data on the other cases involved in this apparent outbreak of pulmonary histoplasmosis., Results: Thirteen of 24 students developed respiratory symptoms following the expedition. Chest X-ray appearances were often suggestive of miliary tuberculosis but in most cases a final diagnosis of histoplasmosis was made (confirmed with serology in five cases, clinically diagnosed in six, and retrospectively suspected in two). Detailed questioning indicated that the likely source was a large hollow bat-infested tree within the rainforest., Conclusions: This is an unusual outbreak of histoplasmosis following short-term travel to Africa. Pulmonary histoplasmosis should always be considered in the differential diagnosis of an acute febrile respiratory illness in travelers returning from endemic areas or reporting activities suggesting exposure., (© 2013 International Society of Travel Medicine.)

History and Admission Findings: We report on a 57-year-old patient presenting with progressive malaise, joint pain and skin rashes one month after visiting Costa Rica. After exclusion of common tropical diseases empiric antibiotic therapy was initiated, however, the patient's symptoms did not improve., Investigations: CT scan of the chest demonstrated an intrapulmonary nodular lesion. Bronchoscopy revealed no pathological changes. Microbiologic analysis of the bronchoalveolar lavage fluids identified no pathogen. An abdominal ultrasound examination did not reveal pathological findings. Serological tests were positive for Histoplasma capsulatum., Treatment and Course: Treatment with itraconazole resulted in a fast initial clinical improvement, but complete resolution of all symptoms only occurred after completion of a 6-months course of itraconazole. Serial CT scans demonstrated a continuous regression of the pulmonary lesion., Conclusion: Histoplasmosis has a low incidence among travelers. However, histoplasmosis should be considered in patients with respiratory symptoms and history of travel to endemic countries, specifically when common traveler diseases have been excluded. Diagnosis is confirmed by serology, imaging and ultimately by biopsy for histological, cultural and molecular identification of the pathogen. Antimycotic drug therapy is the recommended treatment of choice for symptomatic cases., (© Georg Thieme Verlag KG Stuttgart · New York.)

Brain infection by the fungus Cryptococcus neoformans results in inflammation of the meninges and brain parenchyma, a condition known as meningoencephalitis. One million people are estimated to suffer cryptococcal meningitis globally and >60% of these cases die within 3 months of diagnosis. Humans are believed to contract infection by inhalation of spores or dried yeast cells, which subsequently colonize the lung tissue. In the lungs, cryptococci may be cleared by the lung phagocytes, stay latent, cause pulmonary infection and/or disseminate to other body parts, preferentially the brain, culminating in cryptococcal meningoencephalitis. In this review, we discuss the pathogenesis of C. neoformans from the environment to the brain, the current understanding of the mechanisms of cryptococcal transmission into the brain and cryptococcal meningitis. We also give an insight into future cryptococcosis research and the development of novel therapies.

We report transmission of Blastomyces dermatitidis fungal infection from a pet kinkajou to a man. When treating a patient with a recalcitrant infection and a history of an animal bite, early and complete animal necropsy and consideration of nonbacterial etiologies are needed.

More than 110 years of study of the Cryptococcus neoformans and Cryptococcus gattii species complex has resulted in an enormous accumulation of fundamental and applied biological and clinical knowledge. Recent developments in our understanding of the diversity within the species complex are presented, emphasizing the intraspecific complexity, which includes species, microspecies, hybrids, serotypes and genotypes. Each of these may have different roles in disease. An overview of obsolete and current names is presented.

Our observation of histoplasmosis cases augments the current knowledge on transmission by bats. In the presented cases, the only contact happened in the proximity of a bat cave but not inside the cave. We wish to communicate and stress that even outside of caves, bats may disperse the organism.

Respiratory infections in intubated patients can derive from endogenous or exogenous sources. The major route for acquiring endemic ventilator-associated pneumonia (VAP) is oropharyngeal colonization by endogenous flora and leakage of contaminated secretions into the lower respiratory tract. However, a not inconsiderable percentage of VAP results from exogenous nosocomial colonization, especially pneumonias caused by resistant bacteria such as methicillin-resistant Staphylococcus aureus and multiresistant Acinetobacter baumannii or Pseudomonas aeruginosa, as well as by Legionella spp or filamentous fungi, such as Aspergillus. This article reviews the pathogenesis of VAP and the role of the intensive care environment as a source of pathogenic microorganisms.

A North Carolinian developed fatal coccidioidomycosis immediately after bilateral lung transplantation. The donor had previously traveled to Mexico, and the recipient had no travel history to an area where Coccidioides immitis is endemic. Immunosuppressive therapy of the transplant recipient likely reactivated latent Coccidioides infection in the donor lungs, leading to posttransplant coccidioidomycosis.

Objectives: To describe and investigate the cause of an outbreak of 10 cases of nosocomial invasive infection with Aspergillus flavus in a hematologic oncology patient care unit., Design: A retrospective cohort study., Setting: The hematologic oncology unit of a comprehensive cancer center., Patients: Ninety-one patients admitted to the hematologic oncology service between January 1 and December 31, 1992, for 4 or more consecutive days were included in the study., Results: Ten (18%) of 55 patients admitted from July to December 1992 were diagnosed as having invasive aspergillosis compared with 0 (0%) of 36 patients admitted from January to June 1992 to the same patient care units. Patient characteristics, mortality rate, autopsy rate, and admitting location did not change significantly during the course of the year to result in a sudden increase in the number of aspergillosis cases. The source of the outbreak was the high counts of Aspergillus conidia determined from air sampling in the non-bone marrow transplant wing during the outbreak. After high-efficiency particulate air (HEPA) filters were installed as an infection control measure, there were only two additional cases of nosocomial aspergillosis in the 2 years following the outbreak., Conclusions: This outbreak occurred among hematologic oncology patients with prolonged granulocytopenia housed in an environment with neither HEPA filters nor laminar air flow units. Our data demonstrate that in the setting of an outbreak of aspergillosis, HEPA filters are protective for highly immunocompromised patients with hematologic malignancies and are effective at controlling outbreaks due to air contamination with Aspergillus conidia.

In October 1998, a patient developed deep surgical-site and organ-space infection with Aspergillus fumigatus 11 days after undergoing liver retransplantation; subsequently, 2 additional patients in the transplant intensive care unit had invasive pulmonary infection with A. fumigatus diagnosed. It was determined that debriding and dressing wounds infected with Aspergillus species may result in aerosolization of spores and airborne person-to-person transmission.

Case History: Four males (age 25 to 40 years) and one female (age 25) were admitted to our hospital almost simultaneously with symptoms of fever up to 38 degrees C, dry cough, thoracodynia, dyspnoea, myalgia and arthralgia. All patients belonged to a team of eight German bat researchers who had returned from Cuba 10 days before, where they had investigated bats in caves. Another member of the team had only mild histoplasmosis and was followed in our outpatient clinic. Two scientists who wore their breathing masks continuously during their work in the caves did not fall ill., Examinations: Chest X-rays of all in-patients showed pulmonary infiltrates correlating with the severity of their illness. In all patients specific IgG antibodies against Histoplasma capsulatum-antigen were found in the Western Blot assay, confirming the diagnosis of histoplasmosis., Treatment: Treatment with oral itraconazole 200 mg b.d was given to four inpatients for 6 weeks, in the fifth patient itraconazole was discontinued because of an increase of liver transaminases., Conclusion: Antimycotic treatment of advancing histoplasmosis seems appropriate also in immunocompetent patients. The high number of patients within this group suggests high numbers of Histoplasma capsulatum in the caves. Wearing breathing masks throughout the work in the caves may prevent histoplasmosis even in case of high infectious doses. Pre-travel recommendations for cave researchers have to emphasize the continuous use of breathing masks and vaccination against tetanus and rabies.

Pneumonia is one of the most important infectious diseases, both in terms of incidence as well as potential severity. Streptococcus pneumoniae remains the most prevalent etiologic agent, accounting for about two-thirds of bacteremic cases. Diagnostic procedures include chest radiography, blood culture, Gram staining and culture of expectorated sputum, urine antigen assays for Legionella pneumophila and pneumococci, and asservation of an initial serum sample for comparative serologic investigations. Molecular biology techniques continue to gain importance for the diagnosis of Chlamydia pneumoniae, Mycoplasma pneumoniae, Legionellae and viral respiratory infections, however, their availability at present is mainly restricted to research and reference laboratories.

Objective: To study the epidemiologic aspects of a suspected outbreak of nosocomial invasive aspergillosis., Methods: Sixteen Aspergillus fumigatus strains were isolated from bronchoalveolar washings or sputa of 10 patients during a 9-month period. Furthermore, two environmental samples, isolated in a microbiological screening of the hospital, were also available for analysis. Random amplified polymorphic DNA analysis (RAPD) was carried out., Results: The analysis performed by RAPD clearly demonstrated substantial genetic variation among the isolates. Both of the two different primers selected for RAPD analysis (R-108 and AP12h) were able to demonstrate that the strains isolated from all patients infected with the same fungal species and the environmental samples were genotypically distinct. The results by RAPD typing demonstrated that this technique could detect variability among isolates of Aspergillus fumigatus from different patients and even from the same patient., Conclusions: RAPD genotyping proved that the outbreak of invasive aspergillosis consisted of a series of events, non-related, and probably not coming from the same source within the hospital. This type of analysis is an easy, quick and highly discriminatory technique that may help in planning epidemiologic studies of aspergillosis.

Coccidioides immitis is a causative agent of coccidioidomycosis, which is one of the most dreadful mycosis because of its infectious and pathogenic nature. The endemic areas are in the southwestern parts of the United States and other semi-arid regions throughout the Western Hemisphere. During the early 1990s, the incidence of coccidioidomycosis in California increased dramatically, resulting in recognition for this mycosis as a reemerging infectious disease in the United States. The patients included a large number of non-informed visitors from non-endemic countries. Our report is on an imported case of primary pulmonary coccidioidomycosis. A 35-year-old Japanese male, after living in the United States for nine months, suffered from a combination of headache and fever. He was given a serological examination, and a chest radiograph in Phoenix, Arizona in the United States and was diagnosed as coccidioidomycosis. A daily dosage of 400 mg of fluconazole was administered and he returned to Japan. His headache and skin rash persisted and he was admitted to our hospital to evaluate the severity of his disease. There were no fungi cultured from neither bronchoalveolar nor cerebrospinal fluid and he was discharged. The patient had been treated with fluconazole and his symptoms, high-resolution CT and serological antibody titer were monitored. After 18 months, his clinical and radiological evolution was favorable and his serological IgM titer was below its sensitivity medication was stopped and there were no relapses.

Objective: To evaluate efficacy of laminar airflow facilities plus high-efficiency particulate air (HEPA) filtration and HEPA filtration alone in preventing environmental Aspergillus contamination during hospital renovation. To show the usefulness of environmental surveillance to facilitate protection of patients at risk for invasive pulmonary aspergillosis., Design: Prospective sampling of air and surfaces for Aspergillus conidia during 2-year period., Setting: A hematological department adjacent to building renovation at a university hospital., Results: 1,047 air samples and 1,178 surface samples were collected from January 1996 to December 1997. Significantly more air samples were positive for Aspergillus species during the period of building renovation than during the periods before and after renovation in a unit without a protected air supply adjacent to the building work area (51.5% vs 31.7%; odds ratio [OR], 2.3; 95% confidence interval [CI95], 1.4-3.7; P<.001). A major increase in the frequency of positive air samples was also found in another adjacent unit that was protected with HEPA filtration alone (from 1.8% to 47.5%; OR, 48.9; CI95, 12-229; P<10(-7)). In addition, in this unit, the mean count of Aspergillus conidia in positive air samples increased significantly during construction (4 colony-forming units [CFU]/m3 to 24.7 CFU/m3; P=.04) and the proportion of positive surface samples showed a significant increase during renovation (from 0.4% to 9.7%; OR, 28.3; CI95, 3.4-623; P=10(-4)). However, none of 142 air samples collected during renovation in the area protected with laminar airflow plus HEPA filtration showed Aspergillus conidia. In a unit distant from the building renovation site, the results of air and surface samples were not affected by renovation., Conclusion: This study showed a strong association between building renovation and an increase in environmental Aspergillus contamination. Results confirmed the high efficacy of laminar airflow plus HEPA filtration and a high air-change rate. Although filtration with HEPA was effective during normal conditions, it alone was unable to prevent the rise of Aspergillus contamination related to building renovation. This study emphasized the necessity of an environmental survey of airborne contamination related to construction, to facilitate prevention of nosocomial aspergillosis outbreaks. A standardized protocol for aerobiological surveillance is needed.

Basidiospores of Filobasidiella neoformans var. neoformans (progeny of Cryptococcus neoformans MT 100.1 x VR 45980) were able to induce cryptococcosis in Swiss albino mice if inoculated by intraperitoneal injection, nasal instillation or nasal spraying. The latter method, with the aid of a jet nebulizer, was first adopted to imitate the natural entrance of infectious particles. Using this method the small number of basidiospores (7 x 10(3)) could induce cryptococcosis in mice, while the higher number of the parental laboratory-grown yeast cells (1.5 x 10(6)) did not produce infections. By nasal instillation Cyclophosphamide (Cy)-treated mice were more susceptible to the basidiospores, showing 80% cryptococcosis (eight of 10). Seven of the eight infected mice had disseminated cryptococcosis. Immunocompetent mice were more resistant to basidiospore infection than Cy-treated mice, as 40% of that group developed only pulmonary cryptococcosis; none had disseminated infection. Thus, we propose that basidiospores are one form of the infectious propagules of F. neoformans var. neoformans which can cause cryptococcosis, particularly in immunocompromised people.

Children acquire blastomycosis, with rare exceptions, through the respiratory route. Nearly half of those who are infected may be asymptomatic. Cough is the most common symptom and is usually without sputum production, and hemoptysis is not noted. Other symptoms are chest pain (described as tightness or pain when breathing), weight loss, night sweats, and loss of appetite. The severity of illness is variable and may simulate an upper respiratory infection, bronchitis, pleuritis, or pneumonia. As in adults, an overwhelming infection may cause respiratory failure even in immunocompetent children and in immunocompromised children who live in or travel to endemic areas are susceptible to infection. Some reports based on consecutive cases note extrapulmonary dissemination commonly in children, whereas dissemination is rarely noted in outbreak cases. Chronicity of the disease favors extrapulmonary dissemination. Chest radiograph patterns are alveolar infiltrates, consolidation, and nodule(s), and these may be accompanied by cavitation. Diagnosis is suspected when the symptoms that mimic common respiratory infections persist for more than 2 weeks and by a history of residence or travel to an endemic area. Chest radiographic findings of nodule(s) or cavitation further increase the suspicion. Confirmation of diagnosis is by microscopic examination and culture of sputum. When expectorated sputum is unavailable, bronchoscopy with lavage and biopsy or percutaneous needle biopsy of lung is the appropriate next step. Disease that is progressive or severe or disseminated to other organs should be treated. Amphotericin B is effective and results in excellent cure rates. Experience using oral azoles is limited in children.

Two patients admitted to two different medical wards of our institution following respiratory decompensation of chronic obstructive pulmonary disease (COPD) were subsequently transferred to the same room of the medical intensive care unit (ICU) and intubated. Both patients developed invasive pulmonary aspergillosis and died soon after. Because COPD itself is rarely associated with lethal pulmonary aspergillosis, both cases were reviewed, and a retrospective investigation was conducted. Both patients had repeated sputum cultures while on the medical ward before their admission to the ICU; none of the sample grew Aspergillus spp. A. fumigatus was found in tracheal aspirates of both patients from the first day of their intubation while in the ICU. The pulmonary condition of both patients worsened, and invasive aspergillosis was diagnosed by bronchoalveolar lavage. Despite therapy with amphotericin B, the patients died 16 and 22 d after intubation, respectively. Both deaths were attributed to pulmonary aspergillosis; autopsy confirmed a massive pneumonia of the five lobes due to A. fumigatus in one patient. Investigation revealed that an air filter had been replaced 30 h before the first patient was admitted to the room. Experimental air filter replacement performed 12 d after the second patient died revealed the presence of A. fumigatus on the surface of the filters as well as a 10-fold increase in room air fungal counts during the procedure. This study shows that exposure to high concentrations of airborne Aspergillus spp. related to air filter change was associated with fatal invasive aspergillosis in two mechanically ventilated patients. Such infection can be prevented by the establishment and application of guidelines for air filter replacement.

Respiratory failure is the main cause of death in patients undergoing bone marrow transplantation (BMT). In this paper, clinical and research aspects as well as diagnostic, prophylactic and therapeutic strategies concerning the various forms of pulmonary and bronchial complications, which may evolve after BMT, are discussed. Both cytomegalovirus (CMV)-induced interstitial pneumonia (PM) and the idiopathic pneumonia syndrome rarely occur in the cytopenic phase post-BMT. Haematological reconstitution with donor type cells seems to be a prerequisite to the development of these complications, suggesting a key role of immunological reactions. While CMV pneumonia can be effectively treated or prevented by ganciclovir, the idiopathic syndrome is usually fatal. Due to improved prophylaxis and therapy, lethal interstitial PM due to Pneumocystis carinii, herpes simplex, varizella zoster or Toxoplasma gondii as well as lethal PM caused by bacteria or Candida species are comparatively rare events. Aspergillus species, on the other hand, have emerged as frequent causative pathogens in lethal PM during the past years. Prolonged granulocytopenia and prolonged medication with corticosteroids are major risk factors of pulmonary aspergillosis, which is usually fatal; effective prophylaxis may be achieved by sterile air supply during the hospital stay and by inhalation of amphotericin B thereafter. Pulmonary haemorrhage, as diagnosed by bronchoalveolar lavage (BAL), may develop due to the toxicity of the conditioning regimen, or may be secondary to infectious PM of various kind. Congestive heart failure or the application of cytokines might give rise to the development of pulmonary oedema. Patients with hepatic veno-occlusive disease have a high risk of subsequent pulmonary complications, possibly on the basis of toxic lung injury. Venous thromboembolism or air embolism may occur; they are usually venous catheter-associated. Pleural effusions may develop secondary to infection, congestive heart failure, veno-occlusive disease, pulmonary embolism or malignancy. Patients with bronchiolitis obliterans, which leads to progressive respiratory failure, present with an obstructive pattern in lung function tests and hyperinflated lungs on chest radiographs.(ABSTRACT TRUNCATED AT 400 WORDS)

Unfiltered outside air averages 1-15 pathogenic Aspergillus sp. colony forming units (cfu) m-3 although short-term fluctuations are substantial. Seasonal variation reflects increased spore prevalence during periods of greater availability of non-viable matter. In hospital, airborne spores reflect incomplete filtration, infiltration of outside air and shedding of adherent spores from introduced objects. In highly protected hospital areas supplied with air filtered at high efficiency, where aspergillus cfus may be as low as 0.01 cfu m-3, infiltration and shedding contribute a high fraction of ambient spores. Nosocomial aspergillosis occurs in linear proportion to the mean ambient hospital airborne spore content. An analysis presuming a steady-state dynamic equilibrium is imperfect because repeated sampling produces occasional high counts which violate a Poisson distribution. 'Mini-bursts' arise from disturbance of settled spores in dust, shedding spores from clothes or other subtle sources. These sources are best mitigated by increasing the air change rate. It is most important to protect bone marrow transplant patients, leukaemia and lymphoma patients undergoing intensive, potentially curative therapy. The optimal protective environments include high filtration efficiency, point-of-use filters, protection against infiltration and filter bypass, elimination of in-hospital sources, and high air change rates.

A 27-year-old man who habitually smoked marihuana developed clinical, laboratory, and radiologic findings consistent with allergic bronchopulmonary aspergillosis. Culture of the marihuana obtained from the patient's source yielded heavy mixed growths of Aspergillus. Treatment with corticosteroids was effective.

Blastomycosis cannot yet be prevented or controlled, in part because the natural habitat of the causative fungus, Blastomyces dermatitidis, remains ill defined. In investigating 2 outbreaks of blastomycosis that occurred in the summer of 1985 among persons engaged in activities along rivers in contiguous central Wisconsin counties, we isolated B. dermatitidis from soil at one of the riverbanks. Blastomycosis developed in 7 (58%) of 12 residents and guests who had gathered at a pheasant farm on the Tomorrow River in early May, and in 7 (88%) of 8 boys and 1 adult who had visited a site on the Crystal River in early June. Of the 14 patients, 13 (93%) were symptomatic. Two patients visiting the sites only once became ill 23 and 78 days after exposure, respectively. We traced one outbreak to fishing from the bank of the Tomorrow River, and the other to climbing into an underground timber fort along the Crystal River. A culture of soil and organic debris from the fishing site yielded B. dermatitidis. From these and other outbreaks, and studies of endemic disease, we conclude that riverbanks can be a natural habitat of B. dermatitidis, and that the environment around waterways represents the most important site yet identified for transmission of B. dermatitidis.

Approximately 14 days after exploring a limestone cave in northcentral Florida in February 1973, an 18-year-old female developed a respiratory illness with pronounced shortness of breath and cyanosis. The following day, an 18-year-old male presented to the hospital with similar complaints. The association of illness with their recent caving experience prompted further epidemiologic investigation. Twenty-nine members of a church-sponsored youth group explored the implicated cave. Twenty-three of them later became ill with complaints of cough, afternoon fever and sweats, chest discomfort, and dyspnea on exertion. Histoplasmin skin tests were positive in 18 of 24 individuals tested. Serum for complement fixation (CF) was positive in 12 of 26. Testing of area residents revealed a low incidence of skin test and CF positivity (7% and 0%, respectively). That spelunkers are at risk of acquiring pulmonary histoplasmosis has been noted previously; in Florida this has been related to the exploration of caves infested with bats. This is the largest reported outbreak of acute pulmonary histoplasmosis that has been associated with spelunking and further points out that only those individuals who enter the cave are at risk of acquiring the disease, and not those who reside in the surrounding area.

The fungus Histoplasma capsulatum, although commonly found in bat-frequented caves in many countries, has not previously been isolated from that environment in Australia. This report describes the isolation of H. capsulatum from several sources, including cave soil, the organs of mice exposed to the cave environment, and the sputum of a patient clinically diagnosed as having acute pulmonary histoplasmosis after exposure to the cave environment.

Nosocomial fungal pulmonary infections (Zygomycetes, Aspergillus sp.) developed in two premature infants in a special care unit (SCU) adjacent to an area of renovation. Inspection showed that inadequate barriers permitted the passage of airborne particles between the two areas, and cultures confirmed a significantly higher (p less than or equal to 0.05) density of mold spores in the SCU (0.88 cfu per hour per settling plate) compared to a construction-free comparison area (0.22 cfu per hour per settling plate). The major source of mold was the dust above the hospital's false ceiling. In another construction area, imperious barriers were shown to effectively restrict the dispersal of mold. Our experience adds Rhizopus to Aspergillus as a possible cause of construction-related nosocomial infection. Sporadic episodes will continue to occur until the hazards of renovation are appreciated and effective preventive measures are routinely instituted.

The clinical and epidemiologic characteristics of chronic pulmonary histoplasmosis, as compared with the more familiar acute pulmonary histoplasmosis, are relatively unknown. Opinions vary as to the pathogenesis, and only the severe forms of the disease are readily recognized. Over a 22 month period following the excavation of blackbird roost, an unusual outbreak of chronic pulmonary histoplasmosis occurred in a town in southern Kentucky. Thirteen of the cases developed over a span of only four months. An associated outbreak of acute pulmonary histoplasmosis did not occur. During the course of the ensuing investigation, the residential addresses of the affected persons were noted to be clustered about the previously excavated blackbird roost. A case-control study was initiated; the median distance of the residential addresses of the affected persons was found to be 1.0 miles from the roost, compared with 3.2 miles for the control subjects (P less than 0.001). It was concluded that (1) the excavated blackbird roost had served as the common source of the epidemic; (2) the inhalation of exogenous spores accounted for the infections; (3) the spectrum of clinical illness ranged from asymptomatic and mild illness to cavitary disease with considerable morbidity; and (4) following excavation, blackbird roosts may remain an infection hazard for an indefinite period of time.

Specific surveys of the air for Aspergillus fumigatus were carried out in rural and urban situations over a 2-year period. Overall, low concentrations of spores were recorded with a higher incidence during the "winter" months. Counts in the open air and in a hospital ward showed similar fluctuations, the indoor counts being consistently lower. Plant debris in the form of compost heaps and stacks of hay and straw baled with a high moisture content in which self-heating occurs, produces large numbers of spores which may be liberated into the air causing high but localized counts if disturbed. The widespread distribution of decaying leaves following leaf fall represents a potential source of smaller concentrations of spores but over a much larger area. This availability of decaying plant debris with high water content fulfils the growth requirements of Aspergillus fumigatus and is the probable explanation of its winter seasonality.

Six immunocompromised patients housed in widely separated portions of a hospital campus developed invasive aspergillosis during a single month. This represented a significant increase (P less than .001) in the number of cases observed over the 3 years which included this event (19 cases in 36 months). Epidemiological investigation suggested that this cluster of cases was due to a common source outbreak related to construction activity in a central radiology suite serving the hospital. Such non-ward exposures to nosocomial hazards are becoming increasingly important for immunosuppressed hosts.