Instead of sending to one hospital only, the sick coming from garrison and from government ships, several military hospitals ought to be established. Every barrack should have its infirmary, with medical service, and the sick should not have to cross the city to obtain treatment. There is no disease which develops contagious miasm more suddenly than yellow fever. A large accumulation of sick in the same place, is a certain source of disease and contagion.
On board of vessels, a good hygienic system would greatly diminish the number of the sick. In ordinary times, government vessels should not have full crews. The men will then have a sufficient quantity of air to breathe. They should not be drilled in the fierce heat of the sun, or in rain, and they should be required to go to the surgeon, for the least pain in the head.
We have observed, that the incubation of yellow fever, is from ten to twelve days. It will be prudent then, in the heated term, not to remain in port more than six days. English vessels have the habit of not remaining more than three days, but they cruise in the vicinity, or go to Jamaica, so that they are always exposed. The best plan would be to leave the waters of the Gulf, which is the true centre of infection. When, despite every precaution, there are sick men on board, and their condition inspires apprehension, they should be put ashore at once, the vessel whitewashed, and sail set for other latitudes to the north.
Commercial are not under the same conditions as government vessels. On the former all is sacrificed to speculation. The crew is lodged as closely as possible, and ten or twelve men are often seen in a space, where four men can scarcely lie down. The government should require the lodgment of the crew to be on deck, so as to allow free circulation of air. Their food should be wholesome, and well chosen, and instead of giving the crew fresh meat every day, it is better to continue giving them salt meat which is more wholesome, and more nourishing. Let us add, that the meat of the country, bought by merchantmen, is not of first quality.
There are some captains, who, to shun the invasion of the disease, engage blacks to load and unload their vessels, and during this time, leave their crews inactive. This plan is of no avail. The crew is generally composed of strong men, habituated to bodily exercise, which facilitates transpiration. They require, therefore, moderate labor.
The water of the country is bad, and it would be good to add to it a little brandy or rum. This drink is better than wine, or beer, which are adulterated and often give colic.
Prophylactic remedies have been much recommended. In latter times, chlorine on board ships was extolled, and has fallen into disuse, like others I have tried without satisfaction. I have seen a captain, who, convinced of possessing the universal panacea, neglected his sailors, and they became gravely sick. Prophylactics can not have any action on a disease which is in the air. Hygienic precautions and cleanliness, are worth more than these pretended preventives.
Inoculation.—At one time, it was attempted at Havana to prevent yellow fever by inoculation of the poison of a snake, supposed to be the crotalus horridus. A German adventurer assumed the respectable name of Humboldt to sustain his theory. This man had observed that the Indian prisoners, lead from Mexico to Vera Cruz, exhibited, when they were bitten by a viper, symptoms analogous to those of yellow fever. He then made some experiments with the inoculation of this substance at Vera Cruz, and at New Orleans. He came afterwards to Havana, and obtained from General Concha, then Governor of the Island, permission to make some trials at the military hospital. He proceeded in this wise: He made, said he (no one saw it), the snake bite the liver of an animal, and kept it to putrefaction. He inoculated with this substance, and gave at the same time, internally, a syrup composed of mikiana-guaco and rhubarb, with the addition of iodide of potassium and gutta-gamba.
The symptoms appeared in the following order: at the moment of inoculation, the subject was taken with a transient vertigo, at other times, with a nervous trembling, which lasted a longer time. Seven hours after, the pulse was modified in a permanent manner, more frequent or slower, stronger or weaker. Eleven hours after, he had febrile heat. At the end of fourteen hours, he had headache, inappetence, thirst; sixteen hours after, the face red, the conjunctiva injected. From the outset, the gums were swollen and the patient suffered from colic. Eighteen hours after, the gums were painful, and their borders became red, with pains in the salivary glands, and in the nerves of the face and teeth. Nineteen hours after, pain in the lower jaw, in the direction of the submaxillary nerve. At the twentieth hour, bad taste in the mouth, coryza, and œdema of the face; at the expiration of twenty-two hours, a sensation of contraction of the throat, without visible change. At the twenty-third hour, jaundice; at the twenty-fourth, gingival hemorrhage; at the twenty-eighth, conjunctiva injected, chills; at the twenty-ninth, tonsillary angina; at the thirtieth, pains in the loins; at the thirty-eighth, pain in the joints; at the seventy-second, swelling of the lower lip. During convalescence, prurience of the skin, with cutaneous eruptions. These symptoms are far from being those of yellow fever. They belong in part to those produced by the mixture of guaco and iodide of potassium, and in part to those, which putrifying substances produce, when they are absorbed.
M. Humboldt would not yield to the desire of the Commission, to try solely the inoculation and the syrup of guaco. The conclusions of the report were absolutely unfavorable to the experimentalist. The epidemic of yellow fever continuing its course, the proportion of mortality was the same among the inoculated, as among other subjects, and if the statistical tables, presented by M. Humboldt, disagree with the conclusions of the Commission, it is because he had among the inoculated, not only a great number of acclimated persons, but of individuals who had already had the disease. These ideas of inoculation, inspiring a false security, might produce the saddest results. I think, however, that this interesting question might deserve to be studied anew.