DEATH-BEARING WATER IN PHILADELPHIA.
BECAUSE the specific micro-organisms of typhoid fever in sewage-polluted water are not always discoverable, it is argued by some that such foul waters are not the most frequent channels for the dissemination of the disease. This opinion is not unfrequently expressed in Philalelphia, in spite of the testimony which experts have over and over again given to the contrary. The same rule applies to milk, which is frequently the cause of the spread of the disease from the fact of its being taken from a cow either itself infected or one which has been feeding on infected pasture or drinking contaminated water. Often aiso the vessels in which the milk is carried into cities and villages is conveyed in cans which have been washed in polluted water—sometimes such water is made use of to adulterate the milk. But,whether the water or the milk is the source of infection,the closest bact eriological analysis may fail to detect the typhoid germ in such water or milk,for the reason that the special pollutions that are capable of producing typhoid fever are usually intermittent. and, being intermittent, there are intervals during which typhoid dejecta are probably not passed into the water —otherwise the disease would be always much more conspicuously in evidence than it is When, as a result of such contaminations, typhoid fever assumes alarming proportions in the community, attention is then directed to the water that is known to be impure, and a bacteriologist is by some expected to reveal the specific disease-producing impurity. Unfortunately for the Investigation, however.it is begun,as a rule, when the disease is at its height, which is from two to three weeks after the the gross pollution actually occurred—that is, after the interval of time that is necessary for the disease to develop in persons who have swallowed the infective water. Two or thret weeks is quite sufficient time for bacilli to disappear; for they are not normally at home in water, and do not always find in water conditions favorable In their development. In consequence, the efforts of the bacteriologist to find them at the time of his investigations, are, as a rule, rewarded with negative results. Further, when it is borne In mind that the amount oi typhoid excreta capable of seriously polluting a stream is not necessarily large, and that it undergoes in the great volume of water to which it gains access an enormous dilution, it can be fully realized that the bacteriologist, working upon the great mass of fluid with samples rarely larger than a thimbleful, can have but little hope of finding in his tiny sample the organism for which he is seeking.
Applying similar rules to the water supplied to Philadelphia, an expert’s report first gives instances of cities suffering from typhoid fever as the result of the water supply, in which bacteriological proof was not forthcoming; then, passing on to the water supply of the city with which he was concerned, says:
Convincing proof of the quality and character of pollution can easily and always be obtained by any citizen who will inspect the source of our supplies and the course of their flow through the city or who will consult the excellent and exhaustive reports that have been made from time to time by Mr. Hughes, chief of the bureau of house drainage. From these reports may also be seen that the efforts 01 the board of health to check such polluFons have been continuous and in part successful. But their part docs not l believe, extend beyond the city limits. Upon failing to discover the bacillus of typhold fever in the samples of water that we have examined, our attention was given to evidence of another kind that might seem to shed some light upon the source of the outbreak from which the city is now suffering. We believe we have constructed a chain of evidence that will leave little room for reasonable doubt that our water supply is at fault. A study of the weekly reports of the health officer giving the number of cases of typhoid fever and their location by wards demonstrated that the Increase began during the week ending December 4, 1897. It was also noted that the increase in the number of cases reported was largely confined to the wards in the northwes* section of the city Reasoning on the ground that it usually takes from four to eight days from the time of the first manifestations of the sickness until the diagnosis of typhoid fever is marie and reported to the health officer, and estimating that the period of incubation is from seven to ten days, we are brought back to the week ending November 20 as the most probable time for the infection to have taken place. The coincidence of the overflow of the intercepting sewer with consequent sending into the Schuylkill, just above the Queen Lane pumping station, of a considerable amount of sewage on November 16 and the infection of a large number of persons in a well-defined portion of the city with the typhoid bacilli at the same time,was too striking not to be seriously considered and thoroughly investigated It was ascertained, through the courtesy of Mr. J.C. Trautwine, chief of the bureau of water, that the area supplied with water from the Queen Lane reservoir corresponded very closely to the limits of the wards sh wing the largest increase in the number of cases of typhoid fever.
With regard to the overflow of the sewer, it is a matter of record that water, visibly contaminated, was pumped into Queen Lane reservoir on the afternoon of November 16 for some time,probably not exceeding two hours.before the pumps were stopped, which occurred at 4 p. m. The pumps at Spring Garden and Kairmount pumping stations were shut down at 9 p.m.,at which time “ the water at these stations began to have a bad taste.” It is, therefore, clear that, while contaminated water was undoubtedly pumped in the Queen Lane basin, but little contaminated water was pumped by the Spring Garden and Fairmount stations; not only on account of the stopping of the pumps,but chiefly because of the dilution of the sewage, as the Schuylkill was high at the time, owing to the recent rains. Pumping at all the stations was resumed on the afternoon of the 17th, after bacteriological and chemical samples had been taken from the river at the intakes of the various pumping stations and a report of the examination of the chemical had been sent to Mr. Trautwine. It is of importance to know that there had been light, but widespread rains from the 14th of November until the morning of the 17th. This complicated the interpretation of the bacteriological findings, as an increase in the number of bacteria in the water is always expected after a period of rain. It was very difficult, therefore, to determine whether the increase in the number of bacteria was due to the rain or to the sewage.
The rise in the number of typhoid cases in the wards supplied by the Queen Lane reservoir is shown by charts and figures—the inevitable conclusion being that the overflow of the intercepting sewer on November 16, was the cause of the increased prevalence of typhoid fever, first manifesting itself in the city in the week ending December 4.
There seems likewise to be no doubt that the second sudden inciease in the disease which started in the week ending Jannary 1 of the present year—an increase greatest in the Queen Lane reservoir supply area, though considerable also in other portions of the city, especially the Shawmont area—showed that the contamination of the river occurred above the Sh wmoot pumping station; while that the increase in the disease in the Queen Lane area is greater in the Shawmont area would also indicate that the contamination was increased between Shawmont and Queen Lane by further pollutions.
In the neighborhood of Twenty-fifth and Thompson streets there was a large increase of typhoid fever. It was found, however, that the drainage of properties on the latter street, west of Twenty-fifth, Hows over the surface, and during freezing weathers forms ice on the sidewalks. The condition is due to the fact that sewer facilities are not as yet provided for proper drainage.
Regarding the investigation which the chief made of pollution along the Schuylkill river, from the falls of Schuylkill to Lafayette, at the county line; and along the Wissahickon creek and its tributaries, it was reported that a vast amount of drainage has been diverted to the intercepting sewer and branches. The report continues with a statement that original conditions are much improved, and concludes with the following statement:
The cooperation of Montgomery county and the State board of health is necessary to ascertain if the streams flowing into the river are polluted, and to what extent the sewage from the towns lying the river beyond Philadelphia contribute to pollution. I feel sure that, so far as pollution from our city is concerned we supply the minimum quantity of filth contamination.