X1000306-1964-65_Part01 — Page 10

CASES

the introduction of a daily water supply in June, there was a marked decrease in incidence during July and August. In September and October an outbreak of the disease occurred in the Ma Tau Kok area of North-East Kowloon and consequently figures of cases notified during these two months showed a marked increase. Monthly notifications are illustrated in Figure 4.

25. The outbreak, the course of which is shown in Figure 5. was confined mainly to persons living within a small area of the Ma Tau Kok district although a number of cases occurred in persons living elsewhere but working or going to school in Ma Tau Kok. Owing to the comparatively long incubation period of the disease, difficulty was encountered in obtaining accurate information of the patients' eating habits during the critical period, but there was sufficient incrimination of certain restaurants and cooked-food-stalls for action to be taken. Due to the numbers of food handlers involved and the possibility of scanty or intermittent excretion of organisms by carriers. Vi antibody titres were used for screening food handlers to determine those who might be implicated; eight showed litres of 1:64 or higher and were

therefore isolated for further investigation and treatment. Although S. ryphi could not be recovered from any of these persons, the outbreak declined after their removal from food-handling practice.

26. The use of Vi antibody titre for discovery of typhoid carriers has been practised on an experimental and empirical basis. In August. its use enable a few cases amongst children to be traced to two women who were dispensing soft ice-cream; these women had high titres and were subsequently found to be excreting S. ryphi.

Measles

27. In Hong Kong, as in other parts of the world, this disease recurs every two years as a wave of infection spreading throughout children age 0 - 2 years. Such a wave of infection was experienced during the winter months of 1964-65, commencing in December 1964 and reaching a peak in January and February of 1965. The mortality, due mainly to complicating advanced broncho-paeumonia, remained low.

Poliomyelitis

28. The incidence of acute poliomyelitis during recent years is illustrated in Figure 6 and will be seen to have remained low since the

+

6

የነ

5

FIGURE 5

TYPHOID IN MA TAU KOK

AUGUST →

"

SEPTEMBER

DATE OF ONSET

· OCTOBER

CASES NOTIFIED

40

FIGURE 4

POLIOMYELITIS 1558-54

AVERAGE (958-62 1961

*** 1964

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

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