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RESULTS OF WATER ANALYSES
Abbreviations used to describe odors of water: 0, none; 1, very faint; 2, faint; 3, distinct; 4, decided; 5, strong; 6, very strong; a, aromatic;
d, disagreeable; e, earthy; f, fishy; g, grassy; m, musty; v, vegetable
.002.00s| Tr.14.000 55 11.00| 253.0 204.0
02.0:5S| Tr.|0.20|0.70 4.50] 214.00
Tap, public supply
6/5/08| Tr. Tr. 12/70 | Tr.] C1.
3/8/10| . Ci.
4/4/12 Tr. Cl.
Tr. 2 v
225.000 .020.0010.00 0.00 5.00 201.0 190.0
.002.0181.003 7.60 0.70 15.25 343.00 213.0
LINSLY R. WILLIAMS, M.D., Acting State Coinmissioner of Health:
I beg to submit the following report on an investigation of an outbreak of typhoid fever in the city of Utica, made by Mr. E. S. Chase, assistant engineer, acting in cooperation with Dr. J. E. Clark, sanitary supervisor, and Dr. C. N. Hichman, health officer.
On February 2, 1917, information was received hy this Department that several cases of typhoid fever were present in Utica and, as there seemed to be some question as to whether the public water supply might be responsible for the outbreak, an investigation was immediately started by the engineering division to determine the source of the infection.
This investigation included the collection of all facts that might have a bearing upon the cause of the outbreak, and a canvass of all the cases of typhoid was made in order to find out the food or drink supply used in common, and to determine as accurately as possible the date of the onset of the disease. Data were also collected with respert to the supplies of milk, uncooked foods and ice, occupation, association with previous cases of typhoid and all other factors which might possibly have a bearing upon the cause of the infection.
The investigation disclosed the fact that some 49 cases of typhoid had occurred in the city of Utica with onsets since the first of January of the present year. The data obtained with respect to these cases are given in detail in the appended table "A”.
This table has been summarized first to show the prevalence and intensity of the outbreak as indicated by the probable dates of onset as follows:
Probable dates of onset
Jan. 10 ? cases: Jan. 11, 1 case; Jan. 12, 1 case; Jan. 13, 1 case; Jan. 14, 4 cases; Jan. 15, 1 case; Jan. 16, 1 case; Jan. 17, 1 case; Jan. 18, 2 cases; Jan. 19, 1 case; Jan. 20, 4 cases; Jan. 21, 4 cases; Jan. 22, 1 case; Jan. 23, 4 cases; Jan. 24, 3 cases; Jan. 25, 1 case; Jan. 26, 8 cases; Jan. 27, 5 cases; Jan. 28, 2 cases; Jan. 30, 1 case; Feb. 4, 1 case.
From this table it will be seen that the peak of the outbreak occurred during the week of January 21, and, allowing two weeks for the average period of incubation of the typhoid germ in the human system, it is evident that the specific period of infection occurred about the first week in January.
With reference to the milk supply, the table of case data has been summarized to show the milk supplies used by the various cases as follows:
Cases of typhoid on each milk dealers' route
13 9 4 8 14 1
This table shows that there is no particular predominance of cases upon any milkman's route and those dealers which have the most cases are those which have large numbers of customers in that section of the city in which the cases have occurred. Inquiries into the possibility of typhoid cases at the dairies from which the milk is derived led to no information as to such
A careful study of the data indicates that all probability of infection from such other sources as ice, raw oysters, uncooked food, raw vegetables, contact, etc., may be eliminated in the majority of cases. Twenty-one or less
than 50 per cent of the cases gave evidence as to having eaten celery or lettuce around the holidays, at a time when the consumption of such food might be expected to be more or less common throughout the city. In only two cases was there evidence of raw oysters. having been eaten. Three cases may have been due to contact, having occurred in houses in which primary cases have been present, two or more weeks previous. One case may have been due to a carrier, as a sister of this case had typhoid the previous
With respect to sex, the cases are about equally divided, there being 27 females and 22 males. The occupations are diverse and in very few cases is there evidence of common association, such as church, social gatherings or places of work.
The study of the data narrows the field of investigation down to two factors affecting in common the majority of cases. First the localization of residence, the cases, with three exceptions, occurring in the 9th, 11th and 14th wards of the city. These wards, containing approximately 20 per cent of the population of the city, contained 90 per cent of the cases. This lo-alization of the outbreak is also shown by the appended map. The second factor in common is the public water supply.
Excluding the four cases due possibly to contact, it will be seen that 41 cases used the city water unboiled, although in a few instances the water has been boiled since the middle of January but subsequent to the probable period of infection. Of the four cases using boiled water, in the case of two only is there evidence that the water was boiled more or less consistently. By the process of elimination, therefore, the evidence points strongly to the public water supply as the probable source of infection. In this connection it is significant that the outbreak was not of a markedly explosive nature and that there seems to be no preponderance of cases among the younger children. Both these characteristics are indicative of waterhorne typhoid as is also the age distribution. The age distribution at Utica and during two epidemics elsewhere, one due to water and the other to milk is shown by the following table:
The figures for Stamford are from “ Typhoid Fever" by George C. Whipple. The public water supply of Utica is owned and operated by the Consolidated Water Company, and is derived from two principal sources, namely, West Canada creek impounded in the Hinckley reservoir, 20 miles northeast of the city and from a series of reservoirs located just southeast of the city limits. The water from the northern watershed is soft while that from the southern is very hard. The water from the Hinckley reservoir flows first to two reservoirs located 3 or 4 miles north and northwest respectively of the city. One of these reservoirs, known as the Deerfield reservoir, is located three miles north of the city and the main from it enters the city at the foot of Genesee street. This reservoir also receives a small amount of water from Reels çreek, a small tributary to the Mohawk. The other distributing reservoir
known as the Marcy reservoir is located about 412 miles northwest of the city and the main from this reservoir enters the city near the western city line. The distributing reservoir No. 4 on the southern watershed discharges into the city mains at the head of Mohawk street, and also into separate mains supplying the village of New Hartford and a small portion of the city itself.
The mains of the distribution system of Utica are all interconnected and it is therefore possible for the water from any of the three distributing reservoirs to reach any portion of the city. It is probable, however, that the water from the Deerfield reservoir reaches that section of the city east of Genesee street and north of South street and possibly to some extent a snall section west of Genesee street. The water from the Marcy reservoir reaches the villages of Whitesboro and Oriskany with a combined population of upwards of 5,000 and that section of Utica west of Genesee street and north of Hickory street. The water from the southern reservoirs under ordinary conditions probably reaches that section of the city south of South street and east of Genesee street. These boundaries are of course approximate and are given to illustrate in a general way only the distribution of the waters from the various sources throughout the city. The heavy draft upon the supply is in the northern part of the city, which receives mainly the waters from the Marcy and Deerfield reservoirs. Approximately 5,000,000 gallons a day are delivered by each of these reservoirs and 2,000,000 gallons from the southern reservoirs. At night, when the draft upon the system is less than during the day, the water flows through the distribution system from the northern portion of the city toward the southern section, and at this time a back flow may occur into the southern distribution reservoir, due to the fact that the Deerfield and Marcy reservoirs are at a somewhat higher elevation. An automatic hydraulicly-operated gate valve has been installed to stop any excessive back flow which may occur. At times of heavy draft in the northern section of the city the water from the southern water system may reach points in the distribution system nearer north and west than has been indicated in the preceding discussion. At times hard water has been noticed as far north as Court street and as far west as Stark street. Owing to the fact, however, that certain mills require soft water in their process, it is the aim of the water company to maintain soft water in the northern part of the city.
That portion of the city in which the majority of cases of typhoid have occurred is situated in the zone where the pressures from the north and from the south are maintained in a somewhat unstable equilibrium. In other words, it is possible that this particular section of the city may receive water from either the north or from the south, although probably during the greater part of the time from the north, this being due to the necessity of supplying soft water at all times to one of the mills near the northern part of this zone. It is evident that, due to the peculiar conditions of flow and balancing of pressures, the water in the mains in this section is more or less in a state of oscillation, the general flow, however, being in a southerly or southwesterly direction, due to the fact that in the extreme southwestern part of the zone the distribution system terminates at a dead end and also due to the fact that there are several large consumers of water in the southern part of the zone. Furthermore, at times the State Hospital draws heavily upon the system in the western part of this zone.
From the above discussion it will seen that the area in which the cases of typhoid have occurred probably receives during the greater part of the time water from the Marcy distributing reservoir. This reservoir, however. as above stated, supplies the villages of Oriskany and Whitesboro, and the residential portion situated in the northwestern part of Utica itself and in which no cases of typhoid have been reported. Furthermore, the waters from all three distribution reservoirs are sterilized with liquid chlorine, the amount of chlorine ranging from approximately 3 to .4 parts per million. During November and until December 11, however, the southern supply was not treated. No cases of typhoid hare occurred, however, in that section of the city which receives southern rater exclusively nor in New Hartford. A care