A SHORT HISTORY OF OCCUPATIONAL DISEASE: 1. LABORATORY-ACQUIRED INFECTIONS.

Laboratory-acquired infections are as old as laboratories themselves. As soon as the culture of microorganisms was introduced, so too was their transfer to laboratory workers. It is only in relatively recent history that such infections have been fully understood, and methods of spread and their prevention or avoidance developed. This paper endeavours to provide an overview of the history of laboratory-acquired infection and the steps taken, particularly in the UK, for its prevention.

Cerebrospinal fluid protein and glucose examinations and tuberculosis:Will laboratory safety regulations force a change of practice?

Cerebrospinal fluid (CSF) protein and glucose examinations are usually performed in chemical pathology departments on autoanalysers. Tuberculosis (TB) is a group 3 biological agent under Directive 2000/54/EC of the European Parliament but in the biochemistry laboratory, no extra precautions are taken in its analysis in possible TB cases. The issue of laboratory practice and safety in the biochemical analyses of CSF specimens, when tuberculosis infection is in question is addressed in the context of ambiguity in the implementation of current national and international health and safety regulations. Additional protective measures for laboratory staff during the analysis of CSF TB samples should force a change in current laboratory practice and become a regulatory issue under ISO 15189. Annual Mantoux skin test or an interferon-γ release assay for TB should be mandatory for relevant staff. This manuscript addresses the issue of biochemistry laboratory practice and safety in the biochemical analyses of CSF specimens when tuberculosis infection is in question in the context of the ambiguity of statutory health and safety regulations.

[Safety in the Microbiology laboratory]. / Seguridad en el laboratorio de Microbiología Clínica.

The normal activity in the laboratory of microbiology poses different risks - mainly biological - that can affect the health of their workers, visitors and the community. Routine health examinations (surveillance and prevention), individual awareness of self-protection, hazard identification and risk assessment of laboratory procedures, the adoption of appropriate containment measures, and the use of conscientious microbiological techniques allow laboratory to be a safe place, as records of laboratory-acquired infections and accidents show. Training and information are the cornerstones for designing a comprehensive safety plan for the laboratory. In this article, the basic concepts and the theoretical background on laboratory safety are reviewed, including the main legal regulations. Moreover, practical guidelines are presented for each laboratory to design its own safety plan according its own particular characteristics.

[Analysis on status and characteristics of laboratory-acquired vaccinia virus infections cases].

OBJECTIVE: By analyzing the status and characteristics of vaccinia virus laboratory-acquired infections in the bibliographical information, this paper provides relevant recommendations and measures for prevention and control of vaccinia virus laboratory-acquired infections in China. METHODS: Choosing PubMed, Embase, Biosis and SCIE, SSCI, CPCI-S as well as CPCI-SSH covered by Web of Science as the data source, indexing the bibliography of vaccinia virus laboratory-acquired infections, this paper analyzes the information on whether to vaccinate, the occurrence time of symptoms, diseasedparts, symptom characteristics and the disease-causing reasons. RESULTS: The outcome shows that 52. 9% of the cases never get vaccinated, 82.4% engaged in vaccinia virus related researches never get vaccinated in 10 years, 52. 9% get infected by the accidental needlestick in hands during the process of handling animal experiments, 70. 6% of infections occur in the hands and having symptoms after being exposed with an average of 5. 1 days. CONCLUSION: Although it is still controversial that whether or not to be vaccinated before carrying out vaccinia virus related works, it should be important aspects of prevention and control of vaccinia virus laboratory-acquired infections with the strict compliance with the operating requirements of the biosafety, by strengthening personal protection and timely taking emergency measures when unforeseen circumstances occur, as well as providing the research background information to doctors.

Investigation of the first laboratory-acquired human cowpox virus infection in the United States.

BACKGROUND: Cowpox virus is an Orthopoxvirus that can cause infections in humans and a variety of animals. Infections occur in Eurasia; infections in humans and animals have not been reported in the United States. This report describes the occurrence of the first known human case of laboratory-acquired cowpox virus infection in the United States and the ensuing investigation. METHODS: The patient and laboratory personnel were interviewed, and laboratory activities were reviewed. Real-time polymerase chain reaction (PCR) and serologic assays were used to test the patient's specimens. PCR assays were used to test specimens obtained during the investigation. RESULTS: A specimen from the patient's lesion tested positive for cowpox virus DNA. Genome sequencing revealed a recombinant region consistent with a strain of cowpox virus stored in the research laboratory's freezer. Cowpox virus contamination was detected in 6 additional laboratory stocks of viruses. Orthopoxvirus DNA was present in 3 of 20 environmental swabs taken from laboratory surfaces. CONCLUSIONS: The handling of contaminated reagents or contact with contaminated surfaces was likely the mode of transmission. Delays in recognition and diagnosis of this infection in a laboratory researcher underscore the importance of a thorough patient history-including occupational information-and laboratory testing in facilitating a prompt investigation and application of control and remediation measures.

[Prevention of infection transmission in dental laboratories]. / Prevenirea transmiterii infectiei în laboratoarele de tehnica dentara din Iasi.

UNLABELLED: The professional activity in a dental laboratory is associated with a high risk for infection transmission through the manipulation of impressions and prostheses contaminated with patients' saliva and blood. AIM: To assess the compliance of dental technicians in lasi town dental laboratories with the methods used for preventing infection transmission in their practices. MATERIAL AND METHODS: This questionnaire-based survey included 61 dental technicians aged 22 to 58 years from 29 dental laboratories. The 17 questions were related to the protection equipment, air ventilation, and disinfection of surfaces, instruments, impressions, and prostheses. SPSS 14 system, Chi-Square test were used for data analysis, and the levels of statistical significance were set at p < 0.05. RESULTS: 90.2% of the subjects claim the need of prosthetic items disinfection upon arrival at the laboratory from the dental office (p < 0.05). The protection equipment is used by 49.1% of the dental technicians included in this survey (full equipment 18.0%, safety glasses 45.9%, mask 37.7%, rubber gloves 19.6%). 59.1% of the laboratories are provided with air ventilation, while surface disinfection is common practice in 85.2%. Of the study subjects 62.1% disinfect the impressions, 26.1% the final prosthesis, and 25.0% disinfect the interocclusal registrations (p < 0.05). CONCLUSIONS: Educational programs aimed at increasing dental technicians' awareness of infection control by adopting the most effective prevention measures are essential for reducing the incidence of technicians, dentists, and patients; exposure.

Viral infections in workers in hospital and research laboratory settings: a comparative review of infection modes and respective biosafety aspects.

OBJECTIVES: To compare modes and sources of infection and clinical and biosafety aspects of accidental viral infections in hospital workers and research laboratory staff reported in scientific articles. METHODS: PubMed, Google Scholar, ISI Web of Knowledge, Scirus, and Scielo were searched (to December 2008) for reports of accidental viral infections, written in English, Portuguese, Spanish, or German; the authors' personal file of scientific articles and references from the articles retrieved in the initial search were also used. Systematic review was carried out with inclusion criteria of presence of accidental viral infection's cases information, and exclusion criteria of absence of information about the viral etiology, and at least probable mode of infection. RESULTS: One hundred and forty-one scientific articles were obtained, 66 of which were included in the analysis. For arboviruses, 84% of the laboratory infections had aerosol as the source; for alphaviruses alone, aerosol exposure accounted for 94% of accidental infections. Of laboratory arboviral infections, 15.7% were acquired percutaneously, whereas 41.6% of hospital infections were percutaneous. For airborne viruses, 81% of the infections occurred in laboratories, with hantavirus the leading causative agent. Aerosol inhalation was implicated in 96% of lymphocytic choriomeningitis virus infections, 99% of hantavirus infections, and 50% of coxsackievirus infections, but infective droplet inhalation was the leading mode of infection for severe acute respiratory syndrome coronavirus and the mucocutaneous mode of infection was involved in the case of infection with influenza B. For blood-borne viruses, 92% of infections occurred in hospitals and 93% of these had percutaneous mode of infection, while among laboratory infections 77% were due to infective aerosol inhalation. Among blood-borne virus infections there were six cases of particular note: three cases of acute hepatitis following hepatitis C virus infection with a short period of incubation, one laboratory case of human immunodeficiency virus infection through aerosol inhalation, one case of hepatitis following hepatitis G virus infection, and one case of fulminant hepatitis with hepatitis B virus infection following exposure of the worker's conjunctiva to hepatitis B virus e antigen-negative patient saliva. Of the 12 infections with viruses with preferential mucocutaneous transmission, seven occurred percutaneously, aerosol was implicated as a possible source of infection in two cases, and one atypical infection with Macacine herpesvirus 1 with fatal encephalitis as the outcome occurred through a louse bite. One outbreak of norovirus infection among hospital staff had as its probable mode of infection the ingestion of inocula spread in the environment by fomites. CONCLUSIONS: The currently accepted and practiced risk analysis of accidental viral infections based on the conventional dynamics of infection of the etiological agents is insufficient to cope with accidental viral infections in laboratories and to a lesser extent in hospitals, where unconventional modes of infection are less frequently present but still have relevant clinical and potential epidemiological consequences. Unconventional modes of infection, atypical clinical development, or extremely severe cases are frequently present together with high viral loads and high virulence of the agents manipulated in laboratories. In hospitals by contrast, the only possible association of atypical cases is with the individual resistance of the worker. Current standard precaution practices are insufficient to prevent most of the unconventional infections in hospitals analyzed in this study; it is recommended that special attention be given to flaviviruses in these settings.

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.

Risks associated with vaccinia virus in the laboratory.

Vaccinia virus (VACV) is used commonly in research laboratories. Non-highly attenuated strains of VACV are potentially pathogenic in humans, and VACV vaccination and biosafety level 2 facilities and protocols are currently recommended for vaccinated laboratory workers in the United States who handle non-highly attenuated strains of the virus. Despite this, laboratory-related VACV exposures continue to occur and a number of recent instances of VACV infection in non-vaccinated laboratory workers have been documented. We provide a discussion of the usage and risks associated with VACV in laboratory research.

[Laboratory-acquired brucellosis]. / Laboratorieoverført brucellose.

Brucellosis is a rare disease in Denmark. We describe one case of laboratory-acquired brucellosis from an index patient to a laboratory technician following exposure to an infected blood culture in a clinical microbiology laboratory.

Laboratory-acquired vaccinia exposures and infections--United States, 2005-2007.

The last case of naturally acquired smallpox disease, caused by the orthopoxvirus variola virus (VARV), occurred in 1977, and the last laboratory-acquired case occurred in 1978. Smallpox was eradicated largely as the result of a worldwide vaccination campaign that used the related orthopoxvirus, vaccinia virus (VACV), as a live virus vaccine. Routine childhood vaccination for smallpox in the United States was terminated by 1972, but vaccination continues or has been reintroduced for specific groups, including laboratory workers who may be exposed to orthopoxviruses, members of the military, selected health-care workers, and first responders. Severe complications of VACV infection can occur, particularly in persons with underlying risk factors, and secondary transmission of VACV also can occur. VACV is used in numerous institutions for various research purposes, including fundamental studies of orthopoxviruses and use as a vector for the expression of foreign proteins (often antigens or immunomodulators) in eukaryotic cells and animal models. The widespread use of VACV for research has resulted in laboratory-acquired VACV infections, some requiring hospitalization. The current Advisory Committee on Immunization Practices (ACIP) guidelines recommend VACV vaccination for laboratory workers who handle cultures or animals contaminated or infected with nonhighly attenuated VACV strains or other orthopoxviruses that infect humans. This report describes five recent occurrences of laboratory-acquired VACV infections and exposure and underscores the need for proper vaccination, laboratory safety, infection-control practices, and rapid medical evaluation of exposures in the context of orthopoxvirus research.

Four laboratory-associated cases of infection with Escherichia coli O157:H7.

An investigation of four cases of infection with Escherichia coli O157:H7 among laboratorians from different clinical laboratories revealed that the DNA fingerprint pattern of each case isolate was indistinguishable from that of an isolate handled in the laboratory prior to illness. These data suggest that the infections were laboratory acquired, and they demonstrate the importance of laboratorians strictly adhering to biosafety practices recommended for the handling of infectious materials.

Adherence to universal precautions among laboratory personnel in Lebanon.

To evaluate the present situation and plan future directions with regard to implementation of universal precautions in laboratories testing blood samples, we carried out a national cross sectional study in 2003 on a representative sample of laboratories in Lebanon. We compared the results with those of a 1993 study. We found that the education profile of staff had improved, being now more specialized in laboratory science. The discrepancies between what technicians knew, believed in and practised and what was observed in the field improved to some extent in most variables. Disposal of needles and syringes had improved greatly but disposal of blood-contaminated material had not. Given the risks of improper practice, a policy of universal precautions is essential and regular training should be carried out so that staff know and practise the universal precautions and correct laboratory procedures.

Biosafety: guidelines for working with pathogenic and infectious microorganisms.

This unit, in conjunction with local and national guidelines and regulations, provides the basic biosafety information needed to perform the procedures detailed in this manual. Topics discussed include routine precautions when working with biohazards, disinfectants, disposal of biohazards, biosafety levels (as established by the U.S. National Institutes of Health, and the Centers for Disease Control and Prevention), animal facilities, and clinical laboratories. In addition, resources for more information are provided in the Literature Cited and Key References sections and in URLs given text and within the Internet Resources section.

Laboratory-acquired brucellosis.

We report two laboratory-acquired Brucella melitensis infections that were shown to be epidemiologically related. Blood culture isolates were initially misidentified because of variable Gram stain results, which led to misdiagnoses and subsequent laboratory exposures. Notifying laboratory personnel who unknowingly processed cultures from brucellosis patients is an important preventive measure.