View report page

34
subsequently developed Scarlet Fever, but it may have been a
secondary case. The first case sickened on April 21st, and the
second on April 25th.
In two instances the person attacked and one other member
of the family were the only ones who drank raw milk.
In six instances all the members of the household drank
unboiled milk, but in these families only one child under 10
years of age escaped.
The age incidence of the persons attacked was as follows:—
Under 5 years. 5 to 10. 10 to 15. 15 to 25. Over 25 years.
2 7 5 3 3
The dates of notification have already been given, but of
more importance is the date of the onset of symptoms. Of the
20 cases we find the date of sickening as follows:—
Five cases sickened on April 20th, eleven cases on April 21st,
three on April 22nd, and one on April 26th.
The estimation of an incubation is always a difficult matter.
It may be asserted with some confidence that the latent stage
of Scarlet Fever is invariably a short one. The vast majority
of patients take from two to three days to develop their first
symptoms. It has been stated that an incubation of only a
few hours is possible.
Murchison had, in his wide medical experience, found only
13 cases that allowed him to draw any certain conclusions as
to the true incubation. Among these it was
Less than 24 hours 2
24-48 3
Between 2-3 days 1
3-4 „ 2
4-5 „ 3
5-6 „ 2