THOSE living in temperate climates have probably small idea of the virulence of insect and other pests in the tropics. A plague of caterpillars may destroy a season's crop in England, but there is the winter's frost to be passed through before a second attack need be feared. It is otherwise in the tropics. Vegetation is much more luxuriant, and the food supply is permanent; and, when once a plague has obtained a firm foothold, there is no apparent reason why it should cease its ravages before it has entirely destroyed its particular host. It is fortunate for agriculturists that the great increase of any particular parasite seems ultimately to work out its own destruction; and frequently when all hope seems over, the plague rapidly and unaccountably disappears.
About this article
Journal of Parasitology (2007)
Journal of Veterinary Medicine, Series B (1989)
Preventive Veterinary Medicine (1984)