Like the British, the Americans relied primarily upon Atabrine (Mepacrine) to suppress and control malaria.
The lower their morale, the less hope there was of restoring Atabrine discipline and curbing malaria.
To an unknown extent the Marauders helped their enemies by their loose sanitary practices, by command ineptness in supporting the medical establishment, and by defiance of Atabrine suppressive discipline.
A synthetic substitute, Atabrine
, was developed in the US, but an even better drug was made in Germany and when it fell into American hands at the end of the war, the US army copied it and developed the cholorquine compound.