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The circumstances are highly suggestive of a special pathogenic quality of the red heifer's
milk which may possibly have caused first the death of her calf, and then, on the distribution of the
milk in London and Surrey, produced scarlet fever among consumers in those counties. It would
appear that June 7th, the day on which the red heifer's milk first came into use, was the day on
which the milk from the farm first showed evidence of being infective. It is probable that for two
or three days the property of infectiousness was confined to the milk of the red heifer ; but the roan
and white heifers, with which the red heifer had then for some days past been closely associated,
must soon have become also involved. The assumption that the infected milk of one or more of
these heifers, after being distributed on June 7th, 8th, 9th and 10th, was for one reason or another
not distributed on the llth and 12th, but that it and the milk of other cows which had now become
infected was sent to the depot after that date until the time of stopping of the supply from the
depot, would afford a satisfactory explanation of the phenomena of the outbreak.
3. As to spread of infection from cow to cow.-—An hypothesis that a cow disease originated
among newly calved heifers at farm X- appears to require, in further explanation of the sequence of
events, the assumption that there was transference of the diseased condition from cow to cow
involving almost all the milch cows at this farm, the disease then further spreading to some of the
milch cows at farm X1. Such transference, it may be noted, is possible, having regard to the fact that
a particular milker each day milked one or two cows at each farm. (Carter G. L., see page 4.)
4. As to the possible origin of the cow malady.— No information could be obtained from the
milkers as to when this cow malady first appeared in the herd. No admission was made that it had
been observed before the time of our visit. As was mentioned on page 10, we were informed that no
newly-bought cow was brought on to the farm since the first week March. Faute de mieux the
possibility may be considered that the affected animals were infected by food ; a question to which
attention wan called a number of years ago. It was ascertained that the cows were turned out to
grass at the beginning of May; they had had no roots since the middle of April. There was a
supply of hay at each farm, and a supply of cake which was replenished fortnightly was kept at
farm X1, whence cake was from time to time sent to farm X2. The cake (and the statement holds
good for this food alone) was supplied only to milch cows; dry cows had no cake, and, as has already
been noted, the dry cows presented no lesions indicative of the cow malady. Obviously, however, the
escape of the dry cows might be explained by the fact that as they were not milked no infection
could be transmitted to them by the milkers' hands; and in this connection (see page 10) we may
recall the fact that two newly calved cows were also unaffected.
The clinical characters of the disease.
In conclusion, we may briefly refer to some observations that we have been able to collect
with regard to the peculiarities, clinical or other, of the disease in man and in the cow. In connection
with several outbreaks of milk scarlet fever investigated by medical inspectors of the Local Government
Board and medical officers of health, attention has been called to certain anomalies, clinical and
other, which presented themselves ; and the question has even been raised as to whether milk scarlet
fever is or is not identical with scarlet fever ordinarily so-called. The large number of coses,
between 400 and 500, occurring in the present outbreak affords a particularly good opportunity for
investigation of this question, and we have obtained an expression of opinion on the matter from each
of the medical officers of health already named of the districts affected in Surrey, from Dr. Meredith
Richards, of Croydon, and from Dr. Bruce and Dr. Beggs, superintendents of the Western and Grove
Hospitals, to which most of the London patients were sent. All are agreed that the cases were
indistinguishable from ordinary average cases of scarlet fever. If anything, the type of disease was
somewhat mild, but, as Dr. Beggs has pointed out, the age distribution of the cases was slightly
unusual, adults being not infrequently attacked, and this circumstance in itself would explain a
lowered case fatality. Vomiting was a not uncommon initial symptom ; intestinal disturbances
were, in this outbreak, at any rate, quite rare. As regards infectivity, to which question attention
was specially directed, it was remarked in most of the reports that infection from person to person
in the course of this outbreak was uncommon ; only in the report from one district was a different
impression conveyed. It should be added that Dr. Parkes has furnished us with particulars of one
invaded household in Chelsea in which three cases were notified on June 30th ; the dates of onset
(June 15th and 16th) of two of these proved them to have been primary cases, but the date of onset
of the third (June 26th) suggested that this was a secondary case. In connection with this third
case, however, the possibility of a prolonged incubation period, of which cases have been recorded in
recent years, should be borne in mind. There may be further mentioned the possibilities, first, that
the case notified on June 30th was an instance of a relapse, or, secondly, that it was of altogether
independent origin from the cases earlier notified.
Dr. Meredith Richards has kindly furnished us with a detailed statement. He finds that of the
28 cases in Croydon eight occurred in four houses. Of these eight it would seem probable, he says, that
the infection was due to a common origin, having regard to the dates of onset (house A, onset June 17th
and 18th ; house B, onset June 17th and 17tli; house C, onset June 16th and 17th; house D, onset
June 17th and 18th). "Apart from these duplicate cases," Dr. Richards says, " there were no
multiple attacks, and this is all the more striking because there was a considerable number of young
persons living in the invaded houses who had not previously suffered from the disease. The exact
figures were as follows :—
Number of invaded bouses 24
Number of scarlet fever patients 28
Total inhabitants of infected houses (exclusive of the 28 patients) 100
Of the total inhabitants (exclusive of the 28 patients), 17 are stated to have previously had scarlet
fever, 73 are stated not to have had scarlet fever, and concerning the remaining 10 information
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