128
HONG KONG ANNUAL REPORT
Age
1951
C. D.
1952 C. D.
1953
1954
1955
1956
C. D.
C.
D.
C. D.
C. D.
0-4
92 13
94 12
299 16
250 27
205 19
213 1
5 & over
282 16
242 10
363 10
285 10
319 18
347 3
Total.....
374 29
336 22
662 26
535 37
524 37
560 4
0-4 percentage of total
Cases
24.6
45.2
46.7 39.1
38.0
Deaths
28.0
44.8 54.5 61.5 73.0 51.4 0.25
Enteric fever. The case fatality rate for this disease con- tinued to fall, though the number of cases notified was slightly higher than in 1955. A change in the age group distribution of this infection appears to have taken place since 1953, the highest number of cases now affecting children aged 5 to 9 years of age rather than the young adults of between 20 and 24, as was more commonly found in the immediate post-war years.
An immunization campaign was again conducted through- out the second quarter of the year with a view to raising resistance in the population during the peak period of summer incidence. Following these annual campaigns there has been a definite arrest in the prevalence of Enteric fever.
Diphtheria. The lowering of the incidence of this disease, which became dramatically apparent last year, was main- tained but, disappointingly, not materially increased. The immunization campaign was again particularly directed to children under 10 years of age, and the response was good. It is apparent, however, that many very young children still escape immunization and fall victim to this disease.
Measles, Chicken Pox and Whooping Cough. Measles continues to be the principal cause of infant mortality among the notifiable diseases. Notification of cases is certainly incomplete, and this disease is undoubtedly more serious amongst the child population than is generally appreciated. Chickenpox is of importance in Hong Kong because of the danger of confusion with smallpox; whooping cough, another