77. During February and March 1958 the incidence rose consider- ably and the total number of cases notified in the first quarter of the year was 6,807,
Dysentery
78. 550 cases of Bacillary Dysentery including forty three non- Chinese cases were recorded during the year as against $60 in the previous year. 181 notifications were received during the last quarter of the year as compared with 89, 132 and 148 in the first, second and third quarters respectively. The number of deaths and the case fatality rate were, with the exception of last year, the lowest on record, being 9 and 1-6% respectively.
79. The incidence in the 0-4 age group of children remained high, being 190 or 34-5% of the total, as compared with 213 or 38-0% in the preceding year and 250 or 46-7% in 1954, the highest on record.
80. 330 or 60% of the returns were reported on Hong Kong Island as against 184 or 33-4% in Kowloon and 36 or 6-6% in New Territories. 81. During the course of routine investigation one hundred carriers were discovered amongst the contacts and dealt with by Health Officers. 82. Amocbic dysentery and other forms of amocbiasis were notified and 217 cases and eight deaths were ascribed to this infection.
Enteric Fever
83. There was notified a total of 728 cases of typhoid fever which included 723 Chinese and five non-Chinese; twenty six cases of paratyphoid were notified, the lowest figure since 1950. The number of deaths attributed to typhoid and paratyphoid was thirty three giving a case fatality rate of 4-5%, which is the lowest on record.
84. The incidence returns in the 5-9 and 10-14 age groups remained high being 207 or 28-4% and 143 or 19-6% of the total respectively. The age incidence peak occurred again in the 5-9 group for the fifth consecutive year.
85. In contrast to bacillary dysentery, 46-2% of the cases of enteric fever came from Kowloon as compared with 39-6% from Hong Kong Island.
86. T.A.B. inoculation was offered to members of the public throughout the year. During May, June and July, the campaign was intensified and 69,693 first doses. 51,144 second doses and 83,487 booster doses were given as against 118,879 first doses, 88,605 second doses and 120,891 booster doses for the whole year.
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87. Other control measures included general preventive measures in public eating houses and stalls, a search for and supervision of carriers and education of the public in general and personal hygiene. During 1957 a total of thirteen carrriers was detected in the course of the investigation of contacts. The carriers were given treatment by the Health Officer staff.
Chickenpox
88. There were 280 cases, including twelve imported cases, notified during the year as against 273 in 1956. This disease was mainly prevalent during the first four months of the year with outbreaks in schools and other institutions in both the New Territorics and the urban
areas.
Diphtheria
89. 1,239 cases of diphtheria were reported, representing an increase of 525 or 73-5% over the preceding year. This rise was most marked in the last quarter of the year when 770 cases were reported as compared with 258, 94 and 117 in the first, second and third quarters respectively. The strain responsible was identified as a mitie strajn,
90. Deaths attributed to this infection numbered 129 giving a case fatality rate of 104% as against 10-5% in the previous year.
91. Most of the cases occurred in the 0-4 age group, more particu- larly in those under 3 years, giving a total of 626 as compared with 381 in the 5-9 age group and 232 in the group 10 years and over.
92. Out of the total of 1,239 cases, 440 or 35-5% occurred on Hong Kong Island, 575 or 464% in Kowloon, 179 or 14-4% in the New Territories, and 45 or 3-6%. including three imported cases, among the 'floating" population. The incidence was highest in the more congested districts of the urban areas. It is gratifying to note that more notifications were received from Medical Practitioners in private practice and cases are now sent earlier to the Infectious Disease Hospitals for treatment.
93. Prophylactic inoculation against diphtheria is carried out throughout the year and is intensified before the onset of winter when the disease is most active. This has caused a decline in the number of cases and deaths since the disease reached its peak in 1953. However, the number of infants and children immunized each year is not yet sufficient to bring the disease under satisfactory control as there are always sufficient non-immunes available to support a large scale outbreak
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