The sputum of patients suffering from the pneumonic form of the disease is filled with the bacilli. The germs are also found, sometimes at least, in the discharges from the bowels and kidneys. That the infection may be transported in clothing and rags has been long known. The following extract from a memoir by Sir John Hay, then minister from England to Morocco, indicates that the plague was introduced into Morocco in 1826 by means of infected articles of clothing: "The danger from plague by contagion can not, however, to my mind be called in question. That dire disease was introduced into Morocco about the year 1826 by an English frigate, which our Government had dispatched to Alexandria, where the plague was then raging, to convey from that port to Tangier two sons of the Sultan, returning from a pilgrimage to Mecca. No case of plague or other illness had occurred on board the frigate during the voyage, and the Sultan's sons and other passengers were allowed to land at Tangier.
"The customs officers, being suspicious that, in the numerous boxes brought by the pilgrims who had been permitted to embark with the Moorish princes, contraband goods were being smuggled, caused some of the cases to be opened. One contained Egyptian wearing apparel, which the owner said he had bought second hand, and subsequently confessed had belonged to a person who had died of the plague in Alexandria. The two Moorish officials who opened the boxes were attacked with the plague that night and died in a few hours. The disease spread rapidly throughout Morocco, carrying off eighty per cent of those who were attacked."
I mention these facts in order to emphasize the desirability of disinfecting all articles liable to carry the infection coming from infected places.
Professor Haffkine's preventive inoculation against the plague is still being largely employed in India. This consists in injecting hypodermically sterilized cultures of the bacillus. No curative action is claimed for this treatment, but it is believed to be protective against the disease. It is stated that more than eighty thousand people in India have undergone this form of vaccination, and that the death rate among these has been exceedingly low. However, it is well to be careful in accepting statistical statements on a matter of this nature. In the first place, it is probable that only the more intelligent will submit to vaccination, and these will also employ other means of protecting themselves against the disease. In the second place, there are many thousands of people exposed to the infection, or at least live in infected districts, who have never been vaccinated and who do not acquire the disease.
Three kinds of serum have been used as curative agents in the plague. In 1896 M. Yersin began the use of a specially prepared serum in China. The first cases treated with this preparation did unusually well, and it was hoped that most valuable results would follow from its more extended use. This serum is prepared after the manner of the antitoxine used in the treatment of diphtheria. That used most largely in India is made at the Imperial Institute of Experimental Medicine in St. Petersburg. Numerous physicians in India have reported upon the action of this serum, and none of them favorably. Very recently Dr. Clemow treated fifty cases with this serum, and compared them with fifty other cases treated without the serum. Every other case was selected for the serum treatment. The mortality was exactly the same in each group, forty patients out of fifty dying.
The second serum is that prepared by M. Roux, of the Pasteur Institute in Paris. This is practically the same as the preparation made by M. Yersin, and the results obtained are equally unsatisfactory. In 1897 the writer had the privilege of observing, both at Paris and at St. Petersburg, the preparation of these agents, from which at that time great results were expected. A third preparation is made by Professor Lustig, of Florence. I have been unable, so far, to find any detailed account of the method followed by Professor Lustig in preparing his serum. From all that I can learn, however, it is not a serum, but a sterilized bacterial culture; at any rate, Lustig's preparation has proved probably least valuable of all.
At present (July, 1899) the plague prevails throughout India, and has appeared at various places in Baluchistan and Afghanistan, at Samarkand in the Transcaspian Province of Russia; in Persia, at Bassorah and other points along the Persian Gulf; at several places along the western shore of the Red Sea; at Suez and Alexandria; at Tamatave, in Madagascar; at Port Lewis, Mauritius; at Penang, in the Straits Settlements; at Amoy and Hong Kong, China; and at numerous places in Formosa. For reasons already given, it will not be at all surprising should the recent report that the plague had appeared in Constantinople prove to be true. If it once reaches that place, it is more than likely that it will become scattered throughout the Balkan Peninsula. The sad death of Professor Müller and his laboratory servant, at Vienna, from the plague bacillus which Professor Müller brought from Bombay, shows the necessity for caution in handling the germ of this disease.
Are we in America in danger of the plague? I will have to answer this question very much as I did two years ago: "Yes, we are in danger; but this danger, being foreseen, may be easily avoided." In my opinion, our most vulnerable point is along the Pacific coast. With the plague at Hong Kong, it is possible that it may be transferred to Manila, and the transports bringing soldiers to this country may also bring the infection. However, I think the chances of this happening are small. The length of time required to make the voyage from Manila to San Francisco is so great that, with the infection on board, it would be almost certain to manifest itself before reaching our shores, and, knowing its presence on board a ship reaching San Francisco or any other point on the western coast, thorough inspection and disinfection will keep the disease out of this country. The probabilities are that for several years to come the larger cities of India, at least, will remain infected, and our sanitary authorities must be vigilant. The fact that, if the plague reaches us at all, it must come by sea, that a long voyage must be made before it can reach us, and that the disease will most probably appear on board ship before arrival at any American port—all these conditions are in our favor. The General Government should take upon itself the control of all measures to prevent the introduction of infectious diseases from without. Quarantine detention is a relic of ignorance of the true nature of infectious diseases. All transports and other vessels between Manila and this country should be provided with proper disinfecting apparatus. The Government should supply the Marine-Hospital Service with every needed equipment, and if this be done the plague can enter America only through incompetency in that service. There is another source of danger on our Western coast that must not be overlooked. The plague is now widely distributed in Formosa, which is under the control of Japan, and our intercourse with the last-mentioned country should be most carefully watched.