ENTOMOLOGY

CHAPTER IISome Necessary Steps in Any Attempt to Prove Insect Transmission orCausation of Disease 1W: Dwight PierceThe study of the causation of disease is attracting far more attentiontoday than it ever has in the past, but it is to be regretted that there isnot a larger proportion of this effort being directed toward locatingthe possible intermediate hosts and invertebrate carriers.Many excellent investigations have been carried out with all otherphases complete, but the question of invertebrate carriers is often leftin a very indeterminate stage. The majority of the investigations whichhave been seriously undertaken to determine invertebrate carriers havebeen condu.cted on other continents than ours. There is a great field for.investigation along these lines open to the investigators in America. Inorder to stimulate such research, I have attempted in this paper to setdown some of the necessary steps for successful investigation.I. COOPERATIONI consider essential to a thorough investigation of disease transmission,the establishment of a perfect working agreement and heartycooperation between one or more physicians and diagnosticians, one ormore parasitologists, and one or more entomologists. It is not safe,nor docs the effort bring the proper amount of credence, when one manattempts to do the whole work. Each phase of such an investigation!Should be handled by an expert on that phase. The day of the solitaryinvestigator is past and we are now in an era of group-investigationswhich cart:y with them weight and conviction. Of course certain preliminarysteps may easily be taken by anyone member of a proposedgroup or it may be possible that they may arrive at an advanced stageby independent work, but the time will come in each investigation whenII. cooperation of investigators will attain the most satisfactory results.'This lecture was printed in Science, n. s., vol. 50, No. 1284, pp. 12S-180, August 8,1919.25