World Health Organization

The World Health Organization is presented in Rachel Carson’s account as an agency whose malaria-control campaigns reveal the hazards accompanying the replacement of one insecticide with another. When mosquitoes became resistant to DDT, dieldrin was substituted; the resulting poisonings among spraymen and reports of cat deaths in Java make the campaigns evidence of pesticide risks extending beyond their intended targets.

Malaria Control and Dieldrin

The account describes the campaigns as a source of hard-won knowledge about persistent poisons. DDT had been replaced by dieldrin because malaria mosquitoes had become resistant to the earlier insecticide. The change in chemical control was followed by poisoning among the spraymen carrying out the work.

The reported effects were severe: depending on the program, between half and all of the affected men suffered convulsions, and several died. Some men experienced convulsions as long as four months after their last exposure. The delayed episodes underscore the persistence of risk beyond the immediate period of spraying.

Reported Effects on Cats

The book also reports deaths among cats during the World Health Organization’s antimalarial program in western Java. In central Java, so many cats were killed that their price more than doubled. These reports place domestic animals among the unintended casualties associated with insecticide campaigns.

Carson connects the losses to cats’ pronounced sensitivity to insecticides, particularly dieldrin, and frames the Java reports alongside the poisonings of spraymen. The campaigns therefore appear not simply as a switch in the means of mosquito control, but as a recurring instance in which the chosen chemical affected people and animals beyond the targeted insects.

Significance in Carson’s Account

The World Health Organization’s campaigns are invoked as practical evidence about pesticide exposure, including its severity and persistence. Dieldrin’s adoption after DDT resistance developed also shows how the failure of one chemical measure could lead to reliance on another potent poison. The human poisonings and reported cat deaths give that substitution consequences beyond the immediate objective of malaria control.