Laboratory exposure to Coccidioides: lessons learnt in a non-endemic country.

Coccidioides is a primary pathogenic fungus, which infects humans through highly infectious arthroconidia, causing substantial morbidity including life-threatening disseminated infections. Due to the low infectious dose, laboratory personnel might become infected during diagnostic procedures. Accordingly, coccidioidomycosis is reported as the most frequent laboratory-acquired systemic mycosis worldwide. This risk is aggravated in non-endemic countries, where the diagnosis may not be suspected. We report on an inadvertent exposure of 44 persons to Coccidioides posadasii in a clinical microbiology laboratory in Chile, the measures of containment after rapid diagnosis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and the lessons learnt in a non-endemic setting.

Arenavirus infection--Connecticut, 1994.

On August 20, 1994, the Connecticut Department of Public Health and Addiction Services received a report of a case of acute illness in a virologist suspected to be associated with Sabiá virus, a newly described arenavirus. This report preliminary findings from the case investigation.

Lymphocytic choriomeningitis in university hospital personnel. Clinical features.

Clinical manifestations of lymphocytic choriomeningitis (LCM) virus infection in 15 patients are described. These patients were University Hospital personnel who had had contact with hamsters, subsequently shown to harbor the virus. Fever with striking myalgias, headache and rigors were the most common symptoms. Only 2 of the 15 patients had clinically overt and documented aseptic meningitis. Leuikpenia was observed in 10 of 11 patients and thrombocytopenia in 8 of 8 patients tested. A biphasic illness was seen in eight patients. In a patient who has been exposed to laboratory animals, particularly to hamsters, a nonspecific influenza-like febrile illness accompanied by leukopenia and thrombocytopenia may represent LCM virus infection.

Serological evidence of hantavirus infection in laboratory rats and personnel.

Laboratory-acquired haemorrhagic fever with renal syndrome (HFRS) has been reported in many countries. A serological survey of laboratory white rats and of laboratory personnel for antibodies to hantaviruses was conducted in Singapore. Forty-four per cent (143/329) of rats were seropositive by the indirect immunofluorescent antibody test but none had hantaviral antigens in lung tissues. Two of 74 laboratory personnel were seropositive but neither had a history of clinical illness. The high seropositivity rate among laboratory rats led to their replacement with Hantaan virus-free strains. To eliminate the hazard of laboratory-acquired HFRS, regular serological screening of laboratory rats and replacement of infected animals with seronegative stocks should be implemented. High risk techniques with laboratory rats, which are likely to generate aerosols, should be performed in biological safety cabinets. Serological surveillance of laboratory personnel and reporting of suspected HFRS cases are useful in the early detection of hantavirus infection.

A survey of latent tuberculosis infection among laboratory healthcare workers in New York City.

OBJECTIVE: To determine the prevalence of positive tuberculin skin tests (TSTs), incidence of TST conversion, risk factors for positive TSTs, and history of active TB among HCWs in microbiology laboratories in New York City. DESIGN: Two-year survey from May 1999 to June 2001. SETTING: Nineteen microbiology laboratories. RESULTS: During the first year, interviews were conducted with 345 laboratory HCWs (mean, 18 HCWs per site; range, 2 to 51) to assess the prevalence of positive TSTs, but 3 (1%) could not recall their result and were excluded from further analyses. The mean age of the remaining 342 HCWs was 48 years; 68% (n = 233) were female, 54% (n = 183) received bacille Calmette-Guerin (BCG) vaccination, and 71% (n = 244) were foreign born. The prevalence of a positive TST was 57% (n = 196), but only 20% (n = 39) of the HCWs received isoniazid. The incidence of TST conversion in the second year of the study was 1% (1 of 108). Multivariate analysis identified age (odds ratio [OR] per year, 1.05; 95% confidence interval [CI95], 1.02-1.08), foreign birth (OR, 3.80; CI95, 1.98-7.28), BCG immunization (OR, 4.89; CI95, 2.72-8.80), and employment in a mycobacteriology laboratory (OR, 2.14; CI95, 1.25-3.68) as risk factors for a positive TST. Only one HCW had been treated for active TB. CONCLUSIONS: The prevalence of positive TSTs was high among laboratory HCWs, but the TST conversion rate was low. Higher rates of treatment for latent TB infection are desirable.

Chagas disease. American trypanosomiasis.

Chagas disease, caused by the protozoan parasite, Trypanosoma cruzi, is a major source of morbidity and death in Latin America. Many infected immigrants from that region now reside in the United States, posing a risk of transfusion-associated transmission of the organism. Serologic testing is the cornerstone of diagnosing chronic T. cruzi infections, and improved assays are needed. Drug treatment is problematic because the two available drugs can have severe side effects and lack efficacy. T. cruzi infection can be particularly severe in immunosuppressed patients.

Primary cutaneous coccidioidomycosis: a review of the literature and a report of a new case.

A 31-year-old woman working in the laboratory with the mycelial phase of Coccidioides immitis developed a firm, raised, erythematous lesion on the left index finger. A biopsy specimen of the lesion grew a white mold that proved to be C immitis. A sinus tract communicating with the lesion and extending into the proximal phalanx developed. The expressed pus was positive for the tissue form of C immitis by potassium hydroxide and periodic acid-Schiff stains and fluorescent-antibody techniques. The sinus tract was irrigated with an aqueous solution of amphotericin B (Fungizone). The tract closed and the lesion decreased in size. Healing was completed in ten weeks. Primary cutaneous disease must be distinguished from disseminated disease with cutaneous manifestations. In the majority of cases, primary disease heals spontaneously whereas disseminated disease usually requires systemic treatment with amphotericin B.

Biochemical mis-identification of Brucella melitensis and subsequent laboratory-acquired infections.

Brucella species are mis-identified in the API 20NE system as Moraxella phenylpyruvica (profile number 1200004). Since some Brucella spp. grow readily in routine blood culture medium and may be isolated from patients without clinically obvious brucellosis, the risk of laboratory-acquired brucellosis exists. We describe two such cases.

A Japanese case of tinea corporis caused by Arthroderma benhamiae.

We report a case of tinea corporis in Japan caused by Arthroderma benhamiae. A 53-year-old female scientist, who had been working on dermatophytes in a laboratory, noticed pruritic erythema on the outer corner of her left lower eyelid. She used a steroid ointment for three days, but the lesion continued to expand. When she visited our clinic, the erythema was 15 mm in diameter and clearly demarcated with a slightly depressed center. A scale from the periphery of the erythema was positive with direct KOH examination, and T mentagrophytes was isolated from the lesion. The erythema was successfully treated with topical application of butenafine hydrochloride. The isolate was mated with a (+) strain of the Americano-European race of A. benhamiae. Using the most sensitive molecular typing method, restriction exzyme analysis of the non-transcribed spacer region of the ribosomal DNA, the restriction profile of the isolate was the same as that of strains used in her laboratory but different from those of any Japanese isolates associated with pet animals. The results suggest that the patient became infected during her experiment.

[Laboratory-acquired human infection with SP H 114202 virus (Arenavirus: Arenaviridae family): clinical and laboratory aspects]. / Infecção humana adquirida em laboratório causada pelo virus SP H 114202 (Arenavirus: família Arenaviridae): aspectos clínicos e laboratoriais.

Here in is described the clinical and laboratorial findings of a laboratory-acquired infection caused by the virus SP H 114202 (Arenavirus, family Arenaviridae) a recently discovered agent responsible for a viral hemorrhagic fever. The patient was sick for 13 days. The disease had an abrupt onset characterized by high fever (39 degree C.), headache, chills and myalgias for 8 days. In addition, on the 3rd day, the patient developed nausea and vomiting, and in the 10th, epigastralgia, diarrhea and gengivorrhagia. Leucopenia was seen within the 1st week of onset, with counts as low as 2,500 white cells per mm3. Counts performed after the 23rd day of the onset were within normal limits. With the exception of moderate lymphocytosis, no changes were observed in differential counts. An increase in the titer of antibodies by complement fixation, neutralization and ELISA (IgM) was detected. Suckling mice and baby hamsters were inoculated intracerebrally with 0.02 ml of blood samples collected in the 2nd and 7th days of disease. Attempts to isolate the virus were also made in Vero cells. No virus was isolated. This virus was isolated before in a single occasion in São Paulo State, in 1990, from the blood of a patient with hemorrhagic fever with a fatal outcome. The manipulation of the virus under study, must be done carefully, since the transmission can occur through aerosols.

Pulsed-field gel electrophoresis as an epidemiologic tool in the investigation of laboratory acquired Salmonella typhi infection.

Strains of Salmonella typhi implicated in two separate cases of laboratory acquired infection from patients and the medical laboratory technologists who processed the patients' samples were analysed by pulsed-field gel electrophoresis. Although all four isolates were of bacteriophage type E1, PFGE was able to demonstrate that the strains responsible for the two laboratory acquired cases were not genetically related. The PFGE patterns of the isolates from the MLTs were found to be identical to those of the corresponding patients after digestion with restriction enzyme AvrII. This provided genetic as well as epidemiological evidence for the source of the laboratory acquired infections.

[Detection of laboratory infections caused by Junín virus using the neutralization and immunofluorescence technics comparatively]. / Detección de infecciones de laboratorio por virus Junín utilizando comparativamente las técnicas de neutralización e inmunofluorescencia.

To study Junin virus infection among laboratory workers and to compare immunofluorescence and neutralization tests, blood samples were taken from 48 individuals, of which 42 were considered high risk personnel. None of the 16 low risk workers exhibited antibodies. Neutralizing antibodies were detected in 15 high risk laboratory workers. Nine of the latter were already known to carry antibodies from a previous survey in 1978. Titers detected were either at previous levels or slightly higher. Of the remaining 6 out of the 15 positive cases, 3 showed mild clinical and subclinical infection, equivalent to a 12% incidence rate over the 1978-1980 period. An adequate correlation was observed between neutralization and immunofluorescence test: 66.6% for both positive tests and 97.1% for both negative tests. Although the immunofluorescence test ies easier to perform the neutralization test appears to be more reliable clinically. The overall prevalence rate of neutralizing antibodies among non-vaccinated personnel was almost 19%, which warns against the health hazard involved in Junin virus handling.

Outbreak of laboratory-acquired Brucella abortus in Brazil: a case report.

Human brucellosis is an occupational disease affecting workers in slaughterhouses, butcher shops and the milk and dairy product industry as well as individuals who work in clinical or research laboratories. We report the first outbreak of a Brucella abortus infection in a Brazilian laboratory and compare the data obtained with reports available in the literature. Exposure was a result of damage to a biological safety cabinet and failure of the unidirectional airflow ventilation system. An epidemiological investigation identified 3 seroconverted individuals, 1 of whom had clinical manifestations and laboratory results compatible with infection at the time of exposure (n=11; attack rate=9.1%).

Brucellosis in the UK: a risk to laboratory workers? Recommendations for prevention and management of laboratory exposure.

Brucella spp is an uncommon class 3 pathogen isolated in laboratories serving non-endemic areas. This is a report of four recent cases of brucellosis diagnosed at five different London laboratories, and it highlights the need to maintain a high index of suspicion for brucellosis in patients with a history of travel to and/or consumption of unpasteurized foods from endemic areas. A protocol for risk categorisation is proposed, and there is a description of the strategy adopted for serological follow-up of exposed staff and use of postexposure prophylaxis.