Sessional_Paper_1918 — Page 80

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The relative incidence of the disease in crowded and uncrowded districts adds further evidence. As shown above, the disease took its greatest toll from the crowded districts. Among the Europeans the incidence was a 1:1250 among the Chinese it was as 1:509 * Yet epidemic meningitis is not peculiarly a disease of the Chinese. In Swatow, simi-. larly, about sixty cases developed--all among Chinese, who live under the same (or possibly worse) conditions as in Hongkong. On the Trans-Pacific, or the coast-line steamships numerous cases have occurred in the crowded steerage and but rarely has a case occurred among the cabin passengers. Among the Chinese themselves, in the less crowded areas of Kowloon, fewer cases pro rata have developed.

On the other hand, at Canton there were no authenticated cases of epidemic menin- gitis amongst the Chinese, according to the medical authorities at the Canton Hospital. The crowding at Canton is of a different nature from that in the Colony. In the former city, there are too many dwelling houses on too small a space but there are no cubicles within the houses. Each house has two storeys; the upper one usually has an open skylight. Each floor is subdivided into two large rooms with beds along the walls, so that the usual number of occupants, five to seven have sufficient air space; the front and rear walls open completely on to balconies or to the street. In other words the Can- tonese live in better ventilated quarters and are less crowded within their dwellings than the natives of Hongkong.

This evidence based on the relative incidence in crowded and uncrowded living conditions shows the direct influence of crowding upon the dissemination of epidemic meningitis.

The relation of the carrier to the spread of the epidemic offers an interesting study. Of course a carrier is a sine qua non of an infection. He is the source of infection. But the passive carrier per se, that is, the healthy carrier not subject to the influences shown to be contributing to the dissemination of the disease has been found to have had little influence upon the great spread of the epidemic.

Drs. Macfarlane and Earle have shown that the percentage of carriers among Eur- opean contacts was 9.8 per cent. while that among Chinese contacts was 67 per cent. Yet the Chinese by far outnumbered the European cases.

I have found that 24-61 per cent. of 130 inmates of the gaol harbour various types of meningococci, yet not a single case has developed in the gaol. More important is the fact that the living conditions in the gaol, as far as overcrowding is concerned, is more hygienic than in the Chinese community.

The bacteriological evidence obtained from patients suffering from epidemic men- ingitis offers additional proof of the spread of the epidemic by close contact. That almost all (95 per cent.) of the patients examined should be infected with one type, when other types are present in the community command attention. While the evidence is not con- clusive, yet it is very suggestive of the great communicability of the disease directly from one person to another-a condition which is usually brought about by close contact of individuals.

(c.) Other factors contributing to the continuance of the epidemic. The epidemic having gained headway, it is possible that its continuance depends on the constant immigration into the Colony, adding new susceptible individuals to the epidemic areas who come in contact in this way with the sources of infection. To this may be added the unhygienic habits of the natives: the use of common drinking cups and towels; the use of the same and uncleansed food utensils by the numerous patrons of the street and house restaurants; the placing of food directly on streets which are covered with mouth and nose discharges, and indeed, the many ways prevailing in the Chinese community of distributing the nasopharyngeal secretions from one to another.

* According to returns to the Medical Officer of Health. The actual number of cases have been very much greater, as

stated above.