Mr Speaker, Sir, I had originally intended to make a statement before the business of the day on the question of the outbreak of polio, the research that has been made and the final decision of the Government to release the Sabin vaccine, but the introduction of this motion by the hon. Member for Tanjong Pagar has forced me to hold my horses until this debate. I propose now, Sir, to give a full statement on this whole matter and that statement will cover the points which have been raised by the hon. Member for Tanjong Pagar, who has a flair for playing to the gallery and making political capital out of other people's suffering for the benefit of his Party. Until recently, Sir, the only way in which some precautions could be taken against poliomyelitis was by giving standard advice. Until actively immunising vaccines were produced, the measures applied to the disease are given in the Report entitled the "Control of Communicable Diseases in Man" published as an official report of the American Public Health Association. That report from the "Control of Communicable Diseases in Man" published in 1955 has this note - "that the substance of this Report has been accepted by the Ministry of Health for England and Wales and the Department of Health for Scotland with certain reservations to meet international commitments and agreements and differences in legislative and administrative practice in Great Britain." I do not propose to burden Members with a detailed technical discussion. Suffice it to say that the standard advice given there has been repeated continually by members of my Ministry and by myself over Radio Malaya. We asked the people to see that children wash their hands before and after meals and keep away from swimming pools, and so forth. But perhaps I might read one or two of the measures recommended in this report at page 136; Epidemic measures: "Protection of children so far as practical against unnecessary close contact with other persons, especially with other family groups or outsiders during epidemic prevalence of the disease. Urban schools should not be closed nor opening delayed, but intensive or competitive athletic programmes should be postponed..." Furthermore, our health officers, sanitary inspectors, health visitors and other staff have been actively engaged in advising householders. Everything possible to impress on the minds of the people the need for taking these elementary precautions was made, short of addressing each and every householder by letter. Until immunising vaccines became available, such advice could only be given. Without vaccines, the medical profession was, in fact, helpless. Hon. Members may be interested to know that even in countries where sanitary conscience and sanitary discipline are highly developed and where people are likely to observe the advice given almost with religious fervour, particularly in the face of an epidemic, epidemic visitations have recurred. I would like to quote from the Epidemiological and Vital Statistics Report prepared by the World Health Organisation, Sir, Volume II No. 7 of 1958, on the question of the visitation of polio in other countries as late as 1958. In the United States in 1951 there were 28,386 cases with 1,551 deaths - this was not taken over the whole area but in the areas where polio had struck. In 1952 there were 57,879 cases with 3,145 deaths; in 1954, 38,476 cases with 1,368 deaths; in 1956, 15,140 with unknown deaths (this is when the vaccine began to be used); and in 1957, 5,903 cases. In most other countries such as the United Kingdom, Italy, France, Sweden, Australia, the pattern of prevalence has been similar. All the advice, however, does not appear to have retarded in the least the tragic succession of periodic outbreaks. In England in 1951, there were 2,614 cases, and in 1955 6,153. I am saying all this just to show that in the absence of immunising agents, the medical profession is helpless. All the precautionary measures taken were palliatives, both in apology for our helplessness and to appear that something is being done, however futile it may be. When the first few cases of poliomyelitis were notified in late September this year, criticisms were levelled at my Ministry as to why active immunisation was not carried out in order to prevent the occurrence of such an outbreak as we now have in Singapore. I would like to give a short statement of the visitation of polio in Singapore. In 1946, there were 237 cases with an unknown number of deaths; in 1948, there were over 200 cases with 21 deaths; and then there was a steady prevalence. In 1949, there were 76 cases with 2 deaths; in 1950, 82 cases with 10 deaths; in 1951, 81 cases with 9 deaths; in 1952, 55 cases with 10 deaths; in 1953, 43 cases with 5 deaths; in 1954, 71 cases with 3 deaths; in 1955, 24 cases with 2 deaths, and then there was an outbreak in early 1957 of well over 100 cases with 7 deaths. The figures today, Sir, from an analysis which I have got here of cases from August to October, are in August 6 cases, September 32 cases, October 168 cases, and up to 4.30 p.m. yesterday, 26 cases. I have got the breakdown figures, if any Members are interested, the nationality and sex of the victims. Now, poliomyelitis in man, Sir, is essentially an infection of the gut - the alimentary tract in which the virus multiplies. In a very small percentage of cases the virus enters the blood stream and subsequently, in a relatively few cases, may invade the nervous system resulting in paralysis. An infection with polio virus does two things. Firstly, the gut becomes resistant to attack. Secondly, it produces antibodies which circulate in the blood stream and so neutralises the virus that may invade the system. From the statements which I made over Radio Malaya and in the Press, hon. Members are no doubt aware by now that there are two types of vaccines available. One the killed vaccine, which is the Salk, and the other a live vaccine, such as the Sabin. The disease poliomyelitis is now known to be caused by three types of virus, and to effectively immunise a person with the killed vaccine such as Salk, three doses are given by way of injections at stated intervals, the first taking 6 weeks to be effective, and the last dose being given 7 months after the second dose. When this is done the body reacts to the vaccine and produces antibodies which circulate in the blood. It does not, however, prevent the infection of the gut by virulent organisms nor protects any one who may be incubating the disease within this period. Salk vaccine, therefore, provided all the three inoculations have been given, acts as a barrier against the invasion of the nervous system by the virus and so would prevent a paralytic attack. Recent evidence shows that the original figure of 70 per cent protection of persons so inoculated is incorrect and is found to be very much less. There is one thing certain that it does not do, and that is, it does not prevent the infection of the gut and, therefore, does not prevent the inoculated person excreting the virulent virus and so cause disease amongst the non-immune. To be effective as an anti-epidemic measure, the inoculation must be carried out on a very substantial scale and within as short a time as possible. By the importation of large quantities of the vaccine which has only become available recently, and by employing large numbers of persons to carry out the inoculations, and at tremendous expense, involving several million dollars, it is theoretically possible to immunise a large percentage of the population temporarily. Such vaccine, however, does not stop an epidemic in progress. I would like to read the World Health Organisation Technical Report of 1958 - this is the World Health Expert Committee on polio - and I am reading at page 8: "In July 1956, during a period of rising incidence, the Chicago Board of Health initiated a mass vaccination programme in which 1,750,000 doses were injected in less than two months. However, there was no demonstrable effect as to dampening the epidemic." Hon. Members of this House are aware how Government has been pleading with parents in the rural areas to bring their children forward to receive protective inoculation against a far more dangerous and fatal disease than poliomyelitis, namely, diphtheria. This has received some success after prolonged sustained appeals. The response has been poor in the city, possibly because it involves injections, and two visits must be paid. Immunisation with Salk vaccine involves three painful inoculations. An ideal immunising agent for Singapore, therefore, is one that should effectively protect the population against disease and, more important, one that the population will readily accept. An even more important consideration is that the vaccine should be safe to use, and I repeat that, Sir, "the vaccine should be safe to use". If there happens to be a vaccine that does not require a syringe with its threatening needle, if there is one which is pleasing to the children taking it, if there is one which at once produces full resistance to invasion by the polio virus and further produces neutralising antibodies in blood stream and it is at the same time safe to use, this vaccine would be the vaccine of choice. Much research has been carried out in this direction and, as is usual, experimental work has been undertaken in regard to various types of live vaccines. Live vaccines will have the virtue of being administered by the mouth, of effectively immunising the gut and of producing antibodies in the blood stream. The problem has been to develop a virus considerably weakened, I repeat, considerably weakened, yet possessing full immunising properties so that it would not cause the disease in the most sensitive of animals - animals far more sensitive than man is - when injected directly into the spinal cord. Unfortunately, Sir, the co-ordinated series of experiments were interrupted by an experiment on man in Belfast with a strain of virus prepared in 1956 and the methods used did not comply with the strict standards set by the World Health Organisation. When live vaccine is being given by the mouth, the attenuated virus infects the gut, multiplies therein, as does a natural infection, and are excreted in the stools. It so happened that in this particular experiment in Belfast, the outgoing virus in a number of cases reverted to full virulence. That is the virulence acquired through passage, and the experiment was found dangerous and called off. That experiment produced a real scare. It was widely publicised, and the medical profession certainly and some members of the public are aware of this experiment. The dangers inherent in the experiment in Belfast did not deter research which continued, and it is now possible to produce a live vaccine like the Sabin that would both be safe and would prevent the gut from such further invasion of the virus and, at the same time, produce antibodies in the blood stream, and when excreted would not revert to virulence. Late in 1956, a batch of over 10,000 doses of a highly attenuated vaccine produced by Professor A.B. Sabin, and which conforms with the World Health Organisation Expert Committee's rigid standards, was sent to Professor J. H. Hale, Professor of Bacteriology of the University of Malaya, for field trials. Professor Hale carried out experiments among European and other volunteers with this vaccine, and over a considerable period of time, in order to assess its safety, watching carefully to see whether any virulent virus would be excreted. Simultaneously also in other countries experimental research with this type of vaccine was undertaken. In the meantime, Sir, the World Health Organisation had appointed an Expert Committee comprising eminent virologists from twelve different countries to further study the problem of poliomyelitis and the use of vaccine. Now the members of that Conference were Israel, Australia, Scotland, Sweden, South Africa, Singapore (Professor Hale attended), Japan, Canada, United States, France, Poland and Russia. They sat in Geneva from 15th to 20th July, 1957. The Report was published in 1958 and that Committee's Report was received by this Ministry on the 13th of August this year. The Ministry immediately entered into discussions with Professor Hale, who was a member of that Expert Committee, regarding the cautious statements contained in the Report, but the discourse appearing on page 24 of the Report shows that studies with the most highly attenuated strains, one of which is Sabin, showed that the excreted virus was harmless even when injected directly into the spinal cord of the most sensitive of animals - animals more sensitive than man is to poliomyelitis. The Committee itself was so convinced of its safety and efficacy that it made certain recommendations which I will read.