448 SANITARY ENTOMOLOGY 



Watkins-Pitchford found that these stages can be killed with dip much 

 weaker than is necessary' to destroy the adults. He thus determined on a 

 strength which would destroy these young stages with one dipping and 

 yet produce no injury to the host if applied at three-day intervals. The 

 adults are subjected to two dippings, as they remain on the host 7 days. 

 This was found to give 100 per cent destruction. The fornmla (English 

 measure) for this dip is: 4 pounds arsenite of soda (80 per cent arsenic), 

 3 pounds soft soap, 1 gallon paraffin, 400 gallons water. The majority of 

 stockmen, however, do not resort to either the three- or five-day dipping 

 except when in fear of an outbreak of the disease. There is no doubt 

 that by dipping at weekly intervals during the warmer period of the 

 year and at intervals of two or three weeks through the cooler weather, 

 if practiced consistently for two or three ^^ears, the ticks can be reduced 

 to a negligible quantity, if not eradicated, 



African Relapsing Fever Tick. — While this species has received con- 

 siderable attention from the disease transmission and biologic standpoint, 

 little work has been done on control practices. No doubt control of the 

 tick in native huts will be very difficult on account of lack of interest 

 and cooperation on the part of the natives ; however, it would appear to 

 be comparatively easy to protect the houses of white inhabitants from 

 infestation, and for the traveler to avoid attack. The latter could be 

 accomplished best by avoiding infested huts and improvising methods of 

 isolation either in hammocks or otherwise. In native villages the free use 

 of strong tickicides on the floors, and cleaning and airing of mats would 

 undoubtedly reduce infestation and of course the provision of some 

 sort of isolated bedsteads, which suggestion would probably not be taken 

 up by the natives, would also prevent attack. 



The Control of Ticks in Other Parts of the World. — In Australia 

 much progress has been made in the destruction of the cattle tick, but in 

 other parts of the world outside of the United States little systematic 

 work has been done against ticks. The hand application of insecticides 

 or hand picking of adult ticks has been the principal method followed. 

 No doubt many of the control practices put into effect in this country 

 could be adapted to European and Asiatic conditions. 



Treatment of Tick Bites. — There are many references in literature 

 and popular ideas regarding the painfulncss and poisonous nature of bites 

 of various species of tick. Literature contains references to deaths within 

 a few hours following the bite of some tick in the region of Persia. In 

 Mexico there is also an opinion entertained that certain species of Orni- 

 thodoros produce very painful, if not deadly bites. In the experience of 

 the writer and various other workers, most of these reports appear to be 

 unfounded or exaggerated. No doubt the effect varies in different indi- 

 viduals and possibly there is a relationship between the symptoms pro- 



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