Current Strategies for Controlling/Eliminating Opportunistic Microorganisms

Abstract

The strategies used to control or eliminate opportunistic microorganisms from an animal colony depend on these organisms' risk to institutional research programs. The research benefits of controlling or eliminating the microorganisms must be balanced against the control measures' cost, complexity, and probability of success. A nonessential control strategy may be so complicated, expensive, and time consuming that it is circumvented (intentionally or unintentionally) by those expected to use it. In this paper, we outline an approach for analyzing the risk associated with each organism and for developing a control strategy that includes consideration of the research requirements, numbers of animals at risk, and available facility resources. RISK ASSESSMENTFor this discussion, risk assessment is the process of analyzing the nature and relative importance of a microorganism to a research program. Certainly, all risks are relative. For example, a virus such as sialiodacryoadenitis virus (SDAV 1 ) produces clinical signs in naive animals and can affect various physiological and metabolic functions (Bhatt and Jacoby 1985). Such a virus is likely to be of concern for more research programs than a bacterium such as Corynebacterium bovis (otherwise known as hyperkeratosis-associated coryneform species), which may cause disease and research effects only in glabrous mice (Clifford and others 1995).In very general terms, microorganisms can be ranked according to their established potential to cause disease and research interactions. This ranking should be based on data in the peer-reviewed literature coupled with the organism's ability to cause disease or research interactions in the absence of predisposing factors. A simple ranking scheme is provided in Figure 1. To evaluate the risk imposed by a William J.

Biology and Diseases of Mice

“…(4) Interpretation of test results and resulting strategies to eliminate or contain infection should be based on a thorough knowledge of the agent under consideration, its potential effects on mice knowingly or potentially exposed, and the validity of the testing and surveillance methods. Because effective surveillance strategies will vary with research needs and operating conditions, it is prudent to consult at least several literature sources about options for testing and monitoring for infectious agents and disease before launching or modifying a surveillance program (Barthold, 1998;de Souza and Smith, 1989;FELASA, 1994FELASA, , 1996Lindsey et al, 1991a;Lussier, 1991;Nicklas et al, 1993;Rehg and Toth, 1998;Small, 1984;Waggie et al, 1994;Weisbroth et al, 1998;White et al, 1998). There are also recommendations regarding specific agents in following sections.…”

Generating Mice with Diverse Microbial Experience

“…Although these specific practices are dependent on the institution, the goal of excluding pathogens permeates most policies and procedures in SPF vivaria. The type of housing and sanitation, use of personal protective equipment and aseptic techniques, importation and movement of animals, and even the screening of biologics are dictated in part by the goal of protecting the animal colony from unwanted microorganisms (White, Anderson, Geistfeld, & Martin, 1998).…”

Gnotobiotics

“…Trexler held a workshop at the LOBUND Institute to educate commercial animal suppliers and the laboratory animal science community about the application of gnotobiotic technology for producing SPF mice (Trexler, 1961). Thus, one of the most important contributions of gnotobiotics was the technologyenabling production and maintenance of disease-free laboratory animals for biomedical research (Foster, 1959;Weisbroth et al, 1998;White et al, 1998). Animal suppliers recognized that gnotobiotics could be used to develop and maintain nucleus colonies of mice and rats that could be expanded to SPF production colonies.…”