Microbiology and Immunology

Animal models of infection WORLD OF MICROBIOLOGY AND IMMUNOLOGY

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AAnimal models of infectionNIMAL MODELS OF INFECTION

The use of various animals as models for microbiological

infections has been a fundamental part of infectious disease

research for more than a century. Now, techniques of genetic

alteration and manipulation have made possible the design of

animals so as to be specifically applicable to the study of a

myriad of diseases.

The intent for the use of animals as models of disease is

to establish an infection that mimics that seen in the species of

concern, usually humans. By duplicating the infection, the rea-

sons for the establishment of the infection can be researched.

Ultimately, the goal is to seek means by which the infection

can be thwarted. Development of a vaccineto the particular

infection is an example of the successful use of animals in

infectious disease research.

The development of the idea that maladies could be

caused by bacterial infectiongrow from animals studies by

Louis Pasteurin the mid-nineteenth century. The use of ani-

mals as models of cholera and anthraxenabled Pasteur to

develop vaccines against these diseases. Such work would not

have been possible without the use of animals.

Subsequent to Pasteur, the use of animal models for a

myriad of bacterial and viral diseases has led to the production

of vaccines to diseases such as diphtheria, rabies, tuberculo-

sis, poliomyelitis, measles, and rubella.

Animal models are also used to screen candidate drugs

for their performance in eliminating the infection of concern

and also to evaluate adverse effects of the drugs. While some

of this work may be amenable to study using cells grown on

in the laboratory, and by the use of sophisticated computer

models that can make predictions about the effect of a treat-

ment, most scientists argue that the bulk of drug evaluation

still requires a living subject.

A key to developing an animal model is the selection of

an animal whose physiology, reaction to an infection, and the

nature of the infection itself all mirror as closely as possible

the situation in humans. The study of an infection that bears

no resemblance to that found in a human would be fruitless,

in terms of developing treatment strategies for the human

condition.

Drawing depicting Louis Pasteur (right) using an animal model.

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