Considerations for Infectious Disease Research Studies Using Animals

Abstract

Animal models are vital in understanding the transmission and pathogenesis of infectious organisms and the host immune response to infection. In addition, animal models are essential in vaccine and therapeutic drug development and testing. Prior to selecting an animal model to use when studying an infectious agent, the scientific team must determine that sufficient in vitro and ex vivo data are available to justify performing research in an animal model, that ethical considerations are addressed, and that the data generated from animal work will add useful information to the body of scientific knowledge. Once it is established that an animal should be used, the questions become 'Which animal model is most suitable?' and 'Which experimental design issues should be considered?' The answers to these questions take into account numerous factors, including scientific, practical, welfare, and regulatory considerations, which are the focus of this article.

Figure 1.

Design considerations for infectious disease research using animal models. Experimental design for infectious disease research using animal models requires the consideration of the inherent characteristics of the model animal and the infectious organism of interest. Clearly defined research objectives, the animal's response to infection, the similarity of disease in the model system compared with the human condition, and the availability of reagents must be considered alongside the size, cost, availability, anatomy, and safety concerns of the animal species. In addition, ethics and animal welfare must be considered, including medical management and use of humane endpoints. All of these aspects must be developed in the context of national, regional, and local regulations and policies.

Figure 2.

Notable features of animal species used to model human infection with various pathogens. The predominant research application of each model system often varies by species.