Sanitation in Panama

by William Crawford Gorgas

It was evident, therefore, that a number of mosquitoes might have bitten him before he was discovered and cared for. As it would be twelve or fourteen days before these mosquitoes would become infectious, we had plenty of time to attend to them. From the known habits of the stegomyia mosquito we did not think they would leave the house in which they had become infected, though in an individual case this might occur, and a mosquito wander into a contiguous house.

Stegomyia Squad. Havana.

Screened Water Barrel. Havana.

To meet this condition of affairs, as soon as the case was concluded, the house in which the patient had been sick and all the contiguous houses were fumigated with such material as would kill the mosquitoes. In order that the fumigation might be effective the house had to be carefully gone over and all cracks and crevices stopped, so as to make the building as nearly air-tight as in the nature of things it could be made. This was a very laborious process and required care and expert supervision. Most of the stopping of crevices was done with paper and paste. Sulphur is probably the most effective substance in killing the mosquito. The rolled sulphur was used at the rate of about a pound to the thousand cubic feet of space to be fumigated. We generally used the Dutch oven placed in a box of sand or vessel of water, so that in case of a leak, or in case of the oven’s getting too hot, the floor would not catch on fire. With a large force of ignorant men engaged in this work constant watchfulness has to be used to see that fires do not occur. The proper amount of sulphur is placed in the Dutch oven, a little alcohol poured over the sulphur, and a match applied. The sulphur will burn for three or four hours, and will produce very dense fumes which will fill the building and kill all the mosquitoes. The fumes of sulphur in a building which has been well prepared will kill not only all mosquitoes, but all insect and animal life, and is by far the best material to use for this purpose. It is generally somewhat difficult to start the sulphur burning with alcohol alone, and I have noticed that the men got in the habit of using an ounce or two of pyrethrum placed on top of the sulphur for the purpose of starting the fire. The pyrethrum was moistened with the alcohol and would burn for a considerable time after the alcohol was consumed, in almost every instance starting the sulphur burning.

The fumes of sulphur will tarnish gilt metals of all kinds, and injure most light-colored fabrics. This occurs particularly where the air is heavily charged with moisture. In cases in which sulphur was likely to do damage, we used pyrethrum powder. This powder does not tarnish or injure fabrics of any kind. The building must be prepared in the same way as for sulphur, and the vessel in which the pyrethrum is burned must be arranged as above described for sulphur. The fumes of pyrethrum do not generally kill the mosquito, but simply intoxicate her. In the course of time she revives and eventually entirely recovers. For this reason the building should be opened up within a couple of hours after the burning of the pyrethrum, and all mosquitoes carefully gathered and burned.

In almost all dwellings of the better class of tenants there are fixtures and fabrics which will be injured by the fumes of sulphur. Therefore, in this class of buildings we generally used pyrethrum. For fumigating in this same class of buildings where pyrethrum was used we found a mixture of camphor and carbolic acid, one part of camphor to three of carbolic acid, very useful. This should be placed in a tin dish and vaporized with a spirit lamp. The same procedure should be observed as a precaution against fire as is taken with sulphur. The mixture when vaporized gives off dense white fumes which kill the mosquito. Generally, where care has to be taken for fear of injuring fixtures and fabrics, this mixture is preferable to pyrethrum. Pyrethrum should be used at the rate of one pound to the thousand cubic feet, and the camphor mixture at the rate of an ounce for the same space.

In Havana we had to deal with cigar manufactories and tobacco storehouses on a large scale. Here we could use neither sulphur, pyrethrum, nor the camphor mixture, as they all affected the delicate flavor of the tobacco. At first we used to move all tobacco out of a building to be fumigated. This was very laborious and added largely to the cost of fumigation and also tended to drive out from the building the infected mosquitoes before they had been reached by fumigation. Mr. Joseph Le Prince, who was in charge of this work, after much experimenting found that the fumes from tobacco stems did not hurt the flavor of tobacco, and were almost as deadly to the mosquito as was sulphur. We could therefore fumigate with this material buildings where tobacco was stored without injury to the tobacco. The stems were a waste product in cigar manufacturing, and could be obtained in large quantities at little cost. They should be used at the rate of two pounds to the thousand cubic feet, and with the same precautions against fire as are taken in other cases.

Formalin we found useless. It has apparently little effect upon insect life.