Instructions for the prevention of malarial fever : for the use of residents in malarious places.

Date:
1900
Catalogue details

Licence: In copyright

Credit: Instructions for the prevention of malarial fever : for the use of residents in malarious places. Source: Wellcome Collection.

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    mosquitoes, especially the dangerous ones, breed. In such cases the following measures are to be used :— (1) All useless collections of water in which mosquitoes breed should be filled up or drained away, if this can be done at a reasonable cost. (2) If this cannot be done, recourse must be had to the habitual use of culicicides. It is unnecessary to discuss methods of draining or filling up stagnant pools; but the subject of culicicides requires close attention. The simplest culicicide is oil—especially kerosene oil (paraffin). This, if sprinkled on the surface of water, produces a fine film, which destroys the larvae by choking their air-tubes, or perhaps by annulling the surface-tension of the water. But the film must spread all over the surface of the water, and must last for at least half an hour. The oil can be best applied by “painting” the pool with a rag fixed on a stick and first dipped in a pot of oil ; in this manner numbers of pools can be dealt with in five minutes at the expense of very little oil. Perhaps more permanent oils than kerosene would be more permanently effective. Fresh tar dropped in a puddle makes a film like that of oil, and has been favourably reported on. Quicklime has been suggested ; and all these should certainly be tried. But the ideal culicicide still remains to be discovered. It should be some cheap solid substance or powder, which, even when in very small quantity, kills larvae without injuring higher animals, and which dissolves so slowly in water that it will fender a pool uninhabitable for larvae for a long time. Whatever fugitive culicicide is used, it must be used at least once a week. Cisterns and wells of drinking-water should be kept covered in as much as possible.