Laboratory infection

A regular, routine passage of laboratory infections (in natural or nonnatural hosts) may well act as a selection process in itself. Thus, in natural infections the stages that are produced to allow transmission to new hosts... 

Joyce M, Woods CW Antibacterial susceptibility testing in the clinical laboratory. Infect Dis ClinNorth Am 2004 18 401 134. 

Hazard/Risk Group 2 A virus that can cause human disease but is unlikely to be a serious hazard to laboratory workers. Accidental laboratory infection may cause serious infection but effective treatment and preventive measures are available. The risk of spread of infection is limited. 

Hall RA. Laboratory infection of insects by Verticillium lecanii strains isolated from phytopathogenic fungi. Trans BrMycol Soc 74 445-446, 1980. 

Slepushkin AN. An epidemiological study of laboratory infections with Venezuelan equine encephalomyelitis. VoprVirusol. 1959 3 311-314. 

De Mucha-Macias J, Sanchez-Spindola I. Two human cases of laboratory infection with Mucambo virus. Am J Trop Med Hyg. 1965 14(3) 475-478. 

Only about 20% of all known laboratory infections have been traced to specific incidents. The majority ofthe remainder probably came from these ordinary, routine activities. In one comprehensive study, it was found that over 70% of the infections occurring in the laboratory were to scientific personnel, andthat 98% ofalllaboratory-acquired infections were in institutions doing research or diagnostic work. 

The overriding principle for preventing laboratory infections is containment. The purpose is to reduce the exposure of laboratory personnel and other persons to potentially hazardous agents. Containment includes... 

Dangerous/exotic agents which post high risk of aerosol transmitted laboratory infections that are frequently fatal, for which there are no vaccines or treatments... 

Processes in which cells are disrupted and specific components are removed are also prone to produce aerosols since they involve the application of energy to liquids. In the history of laboratory infections these devices and centrifuges have caused a large percentage of the... 

The history of laboratory infection has been covered by various authors over the years " and has formed the topic of an excellent book by Collins. In the early days of medical microbiology, the risk of infection was perhaps regarded as part of the job, with ill health normally arising as a consequence of careless or thoughtless laboratory practice. Bad practice possibly arose partly from a belief in the glamour of medical martyrdom and partly from the under-recognised importance of aerosol transmission. 

Boylan C], Current WL. Improved rat model of Pneumocystis cortmi pneumonia induced laboratory infections in Pneumocystis-free animals. Infect Immun 1992 60 1589-1597. 

Dangerous and exotic agents can be used that can cause severe or lethal human disease. The individual risk of aerosol-transmitted laboratory infections and life-threatening disease is significant. Usually there is no effective treatment or prophylaxis available. The infection could be transmitted directly from one individual to another or from animals to humans. 

All of this data is important in assessing the likelihood of an increased risk of acquiring a laboratory infection. Analyzing the data generated by answering the above concerns can determine the amount of containment necessary to isolate the agent, procedures, or infected animal to minimize risk. We will refer frequently to these principles in the discussions of specific biological hazards later in this chapter. 

Caution See text for instructions for use of table. The data presented in this table must be used only as a guide to the agent summary statements in (378). Laboratory infections have been documented or may potentially occur. See References column for details. From (282, 378). Key H, high probability L, low probability P, potential for infection exists—no risk assessment Y, laboratory infections have been documented. 

A few very highly hazardous arboviruses have been assigned to biosafety level 4, based upon documented cases of severe and frequently fatal naturally occurring human infections and aerosol-transmitted laboratory infections. This group also includes several viruses that are closely related antigenically to some of the high-hazard biosafety level 4 agents. 

Nabarro, J.D.N. 1948. Primary pulmonary coccidioidomycosis case of laboratory infection in England. Lancet 1 982-984. 

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