Rate per 1000 for Chinese
M 52
The following table shows the result of this calculation.
Year Rate per 10000 for non-Chinese 1920 0.118 2.64 1921 (A) 0.191 4.11 1921 (B) 0.176 4.25 1922 0.172 3.22 1923 0.326 *4.32 1924 0.1931 6.31(A) gives results based on the census figures.
(B) gives results based on the estimated population.
The rates for the years 1923 and 1924 invite attention, the former on account of a noticeable increase in the Chinese rate and the latter on account of an unusually high rate for non-Chinese.
The high rate for non-Chinese during 1924 is due to a small but sharply defined epidemic in July and August of that year which was superimposed on the usual incidence of these diseases.
The following table shows the number of cases both Chinese and Non-Chinese of Typhoid and Paratyphoid Fevers notified weekly throughout July and August of 1924. Imported cases are excluded.
Weeks ended Chinese Cases Non-Chinese Cases Total Cases July 7th 2 4 6 14th 2 4 6 21st 1 17 18 28th 6 14 20 August 4th 5 5 10 11th 3 4 7 18th 12 0 12 25th 5 3 8 Sept. 1st 5 4 9A diagram is given to show the number of cases of Typhoid and Paratyphoid Fevers notified during the months of July, August and September 1924.
In viewing this diagram it must be remembered that the cases notified on any day were not necessarily infected on even approximately the same day.
The incubation period of typhoid fever is variable and notifications are made at very different stages of the disease, some being comparatively early and the others late, while some cases are only diagnosed post mortem.