© Hong Kong Academy of Medicine. CC BY-NC-ND 4.0
A smallpox vaccination certificate
WP Mak, FHKAM (Pathology)1; TW Wong, FHKAM (Emergency Medicine)2
1 Chairman, Hong Kong Museum of Medical Sciences Society
2 Director, Hong Kong Museum of Medical Sciences Society
 Full paper in PDF
Compulsory vaccination in Hong Kong began in 1888, when the Vaccination Ordinance was enacted in response to a severe epidemic the year before.1 All infants were required by law to be vaccinated before the age of 6 months, and only vaccination performed by a medical practitioner or a government-appointed public vaccinator was recognised; unauthorised persons who performed inoculations would be penalised. A certificate of vaccination would be issued and the parents were required to register the vaccination with the stipulated government department within a specified period.2
This certificate of successful vaccination (Fig 1) was issued for a smallpox vaccination in January 1950. The vaccinator was a Ms Mei-ching Yip, a midwife who ran a private maternity home in Shanghai Street, Yaumatei, Kowloon. Because the baby was unnamed at the time, it was recorded on the certificate as ‘Tai So’ (大蘇), meaning ‘firstborn boy’. The parents then took this certificate to the Registrar of Births and Deaths where a stamp was made on the right upper corner of the certificate as a proof of registration.

Figure 1. Certificate of successful vaccination (image courtesy of the Hong Kong Museum of Medical Sciences)
Vaccination was an important measure for the control of smallpox in Hong Kong. The vaccines were produced initially by the Vaccine Institute, which was established in 1892. Production was taken over by the Bacteriological Institute in Sai Ying Pun from 1906 until 1973, when the Institute of Immunology was opened in Victoria Road, Pokfulam.3 The smallpox vaccines (Fig 2) were produced using various techniques, including injection of pox viruses into the bellies of buffalo calves. The number of smallpox vaccines produced rose from 8797 in 1906 to 17 536 in 19083 and the vaccines were distributed to various local clinics, hospitals, and maternity homes; the Bacteriological Institute was also able to supply vaccines to some neighbouring cities.4 A variety of special vaccination knives and techniques were used at this time to ensure success.5

Figure 2. Glycerolated smallpox vaccine. The label notes that it was manufactured by the Hong Kong Government’s Institute of Pathology, contained no more than 0.4% phenol and required storage at a temperature below 5°C (image courtesy of the Hong Kong Museum of Medical Sciences)
Around 1950, smallpox vaccination was no longer compulsory and instead became one of the recommended immunisations for a child. As well as the vaccination of newborn babies, revaccination at school entry was also introduced. The last local case of smallpox was recorded in 1952. Hong Kong was declared smallpox-free on 30 July 1979 by the Hong Kong Government and the World Health Organization announced the global eradication of smallpox later that year. On 1 January 1981, smallpox vaccination was formally deleted from the immunisation schedule and supply of the vaccine to medical practitioners was also discontinued.6
1. Chan-Yeung M. A Medical History of Hong Kong: 1842-1941. Hong Kong: The Chinese University of Hong Kong Press; 2017: 211-7. Crossref
2. The Vaccination Ordinance, 1890. Historical Laws of Hong Kong Online. Available from: https://oelawhk.lib.hku.hk/archive/files/7744fd4e98b3640e9f660c2b3d10668a.pdf. Accessed 5 Jan 2024.
3. Starling A, Ho FC, Luke L, Tso SC, Yu EC. Plague, SARS and the Story of Medicine in Hong Kong. Hong Kong: Hong Kong University Press; 2006: 24-5.
4. Ho FC. The Silent Protector–Hong Kong’s Bacteriological Institute, its History and Legacy. Hong Kong: Hong Kong Museum of Medical Sciences Society; 2020: 37-8.
5. Chan-Yeung M. Vaccination knife. Hong Kong Med J 2017;23:670-1.
6. Lee SH. Epidemiological Surveillance of Communicable Diseases [MD thesis]. Hong Kong: University of Hong Kong; 1991: 203-15.