PROPHYLAXIS 



1339 



B. Methods applied to the louse : — 



I. Pedulicides : — 



(a) Dry Heat. — Lice and nits can be killed by exposing them for 



fifteen minutes at 60° to 65° C. 

 (6) Moist Heat. — Lice and nits are killed instantaneously by 

 moist heat at or over 80° C. 

 This is the method most used for clothing, which may be 

 boiled or exposed to steam, but must not be in tightly 

 rolled bundles. 



C. Chemicals : — 



For Use on the Person.- — Kerosene oil or petrol spray or vaseline, or 



cresol soap. 

 For Use on Stored Clothing. — Naphthalene. 

 II. Lice Repellents: — • 



Better-class patients;- — Dusting powder of menthol 3-5 



grains, zinc oxide i ounce. 

 Poorer-class patients: — Naphthalene as a dusting powder. 

 III. Special Points : — 



Head Lice. — Shave the head or cut the hair very short, or 

 wash the hair thoroughly with i in 40 carbolic acid lotion, 

 which is left to act for an hour, the head being wrapped 

 up in a towel in the form of a turban. Then wash the 

 head with soap and water and apply a dressing to any 

 raw areas, carbolic vaseline (2 per cent.) or white precipi- 

 ^:ate aintment may also be used to destroy head lice. 

 Body Lice. — The following drugs arranged in order of effici- 

 ency (according to Castellani and Jackson) may be used : — 



1. Petrol and kerosene oil. 



2. Plain vaseline. 



3. Guaiacol. 



4. Anise preparations. 



5. Iodoform. 



6. Lysol, cyllin, etc. 



7. Carbolic acid, 5 per cent. 



8. Naphthalene. 



9. Camphor. 

 IV. General Insecticides : — 



The experiments of Castellani and Jackson in Serbia have 

 demonstrated that pyrethrum is a very feeble pediculi- 

 cide, while sulphur, boric acid, perchloride of mercury, 

 when used in powder, have no action whatever. 



Substances which may be efficient pediculicides may, how- 

 ever, have little or no action upon other insect parasites 

 of man, such as bugs and fleas. For example, iodoform 

 will kill lice in ten to fifteen minutes, but has no action 

 on bugs and little on fleas. Pyrethrum acts more power- 

 fully upon bugs than upon lice. In order to formulate 

 a general insecticide several chemical substances must 

 be combined. As an example of a general insecticide 

 for use against lice, bed bugs, and fleas, the following is 

 given :■ — 



Equal proportions of naphthalene, previously soaked in 

 guaiacol or creosote, pyrethrum, zinc oxide. 



The wearing of undergarments made liceproof by soaking in 

 various disinfectants (crude carbolic acid and soft soap 

 emulsion), as recommended especially by Bacot, is useful. 

 Legroux's ' sachets ' or small bags containing naphthalene 

 treated with citronella oil may be used. 



