On tlie occasion of his being elected an Honorary LL.D. of the University of Hong-Kong in January, 1919, Dr. Lim Boon Keng, of Singapore, addressed the assembly in the University Hall as follows:—
The author discusses some of the features of the cholera epidemic caused by El Tor vibrios in 1961-62 in the Western Pacific. The disease originated in the Celebes and spread from there to other parts of Indonesia, to Sarawak and, possibly, to Kwangtung. Hong Kong and Macau were most probably infected from Kwangtung. Subsequently the disease reached the Philippines, progressing from Manila southwards to the other islands, whence it invaded British Borneo. The El Tor epidemic did not differ clinically or epidemiologically from other cholera outbreaks observed during the past decade. The disease attacked poor, under-nourished people living under insanitary conditions. It spread along the coastline and, to a limited extent, along inland waterways. The authorities in the affected territories recommended that the quarantine regulations, sanitary measures and treatment methods used against cholera caused by the so-called "true" cholera vibrios be applied also to cholera caused by El Tor vibrios.
All subspecies of black rats (Rattus rattus) used in the present study are characterized by having large and clear C-bands at the centromeric region. The appearance of the bands, however, is different in the subspecies. Chromosome pair No. 1 in Asian type black rats (2n=42), which are characterized by an acrocentric and subtelocentric polymorphism, showed C-band polymorphism. In Phillipine rats (R. rattus mindanensis) the pair was subtelocentric with C-bands, but in Malayan black rats (R. rattus diardii) it was usually acrocentric with C-bands. In Hong-Kong (R. rattus flavipectus) and Japanese black rats (R. rattus tanezumi) it was polymorphic with respect to the presence of acrocentrics with C-bands or subtelocentrics without C-bands. The other chromosomes pairs showed clear C-bands, but in Hong-Kong black rats the pairs No. 2 and 5 were polymorphic with and without C-bands. In Japanese black rats, 6 chromosome pairs (No. 3, 4, 7, 9, 11 and 13) were polymorphic in regard to presence and absence of C-bands, but the other 5 chromosome pairs (No. 2, 5, 6, 8 and 10) showed always absence of C-bands. Only pair No. 12 usually showed C-bands. C-bands in small metacentric pairs (No. 14 to 20) in Asian type black rats generally large in size, but those in the Oceanian (2n=38) and Ceylon type black rats (2n=40) were small. In the hybrids between Asian and Oceanian type rats, heteromorphic C-bands, one large and the other small, were observed. Based on the consideration of karyotype evolution in the black rats, the C-band is suggested to have a tendency toward the diminution as far as the related species are concerned.
Histocompatibility locus A typing of 43 Malaysian Chinese and 51 Hong Kong Chinese patients with nasopharyngeal carcinoma (NPC) confirmed the association between the occurrence of A2-Sin 2 and the increased risk for NPC that was previously demonstrated in Singapore Chinese. The results support the previous interpretation that the histocompatibility locus A genotype of importance in NPC predisposition is the A2-Sin 2 haplotype. The histocompatibility locus A-linked, genetically determined NPC risk is common to Asian Chinese from at least three geographic locations.