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Lesson 17 |
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A man-made disease |
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What factor helped to spread the disease of myxomatosis? |
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In the early days of the settlement of Australia, enterprising settlers unwisely introduced the European rabbit. |
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This rabbit had no natural enemies in the Antipodes, so that it multiplied with that promiscuous abandon characteristic of rabbits. |
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It overran a whole continent. |
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It caused devastation by burrowing and by devouring the herbage which might have maintained millions of sheep and cattle. |
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Scientists discovered that this particular variety of rabbit (and apparently no other animal) was susceptible to a fatal virus disease, myxomatosis. |
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By infecting animals and letting them loose in the burrows, local epidemics of this disease could be created. |
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Later it was found that there was a type of mosquito which acted as the carrier of this disease and passed it on to the rabbits. |
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So while the rest of the world was trying to get rid of mosquitoes, Australia was encouraging this one. |
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It effectively spread the disease all over the continent and drastically reduced the rabit population. |
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It later became apparent that rabbits were developing a degree of resistance to this disease, |
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so that the rabbit population was unlikely to be completely exterminated. |
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There were hopes, however, that the problem of the rabbit would become manageable. |
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Ironically, Europe, which had bequeathed the rabbit as a pest to Australia, acquired this man-made disease as a pestilence. |
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A French physician decided to get rid of the wild rabbits on his own estate and introduced myxomatosis. |
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It did not, however, remain within the confines of this estate. |
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It spread through France, where wild rabbits are not generally regarded as a pest but as a sport and a useful food supply, |
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and it spread to Britain where wild rabbits are regarded as a pest but where domesticated rabbits, |
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equally susceptible to the disease, are the basis of a profitable fur industry. |
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The question became one of whether Man could control the disease he had invented. |
