Measures to Prevent Measles Outbreak in Singapore

Sir, measles is a highly contagious and serious viral disease and vaccination is the most effective protection against this infection. High vaccination coverage at the population level not only protects the individuals but also makes it harder for the disease to spread thereby reducing the risk of large outbreaks. This way, it provides herd immunity which will also protect those who are unable to receive vaccination such as infants under the age of 12 months and those who are immune-compromised. It is therefore important for countries to maintain a high level of vaccination.

In recent years, there has been a global increase in measles outbreaks because of declining vaccination coverage in many countries. This has resulted in a significant increase of non-immune individuals in the community, making it easier for the disease to spread. Being a travel hub, Singapore is also exposed to imported cases. In the first four months of 2019, Singapore saw 43 measles cases, nearly three times more than the same period in 2018 as a result of increased global outbreaks. These were all sporadic cases or cases with limited spread and there was no community outbreak. We are monitoring the global and local situation closely. We have alerted our doctors to look out for measles cases and notify MOH promptly so that actions can be taken to prevent disease spread.

We should also strive to achieve a high level of vaccination in Singapore. Our national immunisation schedule recommends that children should have their first dose of measles vaccine at 12 months of age and the second dose at 15 to 18 months of age. With the exception of those who are unable to be vaccinated because of medical reasons, the measles vaccine is compulsory for local children. Earlier this year, we have also made it compulsory for foreign children applying for long-term passes to be fully vaccinated against measles.

We have also put in place measures to facilitate and encourage vaccination. Vaccination is available free to all Singaporean children at polyclinics. The Health Promotion Board (HPB) sends reminders to parents whose children have yet to complete vaccination by two years old. HPB also provides catch-up vaccination in primary and secondary schools for students who still have not completed their vaccination. The measles vaccination coverage among resident children reached 95% for the first dose at two years of age and 93% for the second dose at seven years of age.

Nonetheless, we cannot be complacent. MOH is looking into ways to raise the vaccination coverage further. Some of the measures being considered include sending reminders to parents ahead of vaccination due dates. This way, we ensure that children are protected as early as possible. We will also look into how we can raise the vaccination rate of children before they enter pre-school and primary school. To protect the more vulnerable populations like infants and the immuno-compromised, we will study ways to ensure that workers caring for them achieve a high level of vaccination coverage.

Even with these measures, we can continue to have sporadic cases of measles due to imported cases. We can expect to see more cases when there is an increase in global outbreaks. I would like to urge parents to bring their children for vaccination when it is due. By working together to improve and maintain a high level of vaccination coverage, we can better protect our population and reduce the risk of large local outbreaks.

I would like to thank the Minister for the very comprehensive response. I have a few supplementary questions. The first is with regard to the measles cases that were reported recently; the increase to 43 cases. Could I just maybe have an understanding of the type of cases? Were they adults, children? Were they imported cases? Just to get a feel of how these cases arose.

The second is with regard to vaccination rates. I note the answer on the vaccination rates with regard to children. I was wondering whether we have data on the overall vaccination rate for the resident population in Singapore. Because if we look at the outbreaks overseas, a lot of cases arose in adults and so on, not just in the paediatric community.

The third supplementary question: I was wondering whether we have some ideas or some knowledge about what are the reasons that certain children or adults refuse to be vaccinated? I think this maybe comes with the next PQ. Does the Ministry think that the anti-vaccination movement and the online misinformation have an important impact on the reason why parents, or maybe adults even, are refusing the vaccination?

The last supplementary question is regarding whether MOH foresees that in the event of an outbreak or even pre-emptively, actions might be taken against unvaccinated individuals? We have seen in other countries there are restrictions on children who are unvaccinated from attending pre-school or even going to school. The German Minister for Health has just proposed that there might be financial penalties for people who are unvaccinated.

I thank Dr Chia for the four supplementary questions. First, for the cases which have been reported during the first four months this year, let me share that among the 43, 33 were not vaccinated. Ten were vaccinated but as all of us know, vaccination may not be 100% effective. Even among those who were vaccinated, up to 3% may not be effective. Therefore, we need to raise the overall population coverage to protect the small number of people who are unprotected despite vaccination.

Among those who were not vaccinated, nine of them were infants before they were due for vaccination. The rest were aged between one and 54. So, there is a wide variation of ages.

For the adults, we do not have specific data on how many of them were vaccinated. But there was a recent study in 2018 on seroprevalence. The study indicated that the vast majority of adults in Singapore had a very high level of immunity against measles. One of the possible reasons could be that in the early 1970s, measles were very widespread, a very common occurrence, and many of us who are adults could remember having measles during that time. Therefore, the naturally acquired immunity arising from actually contracting measles is prevalent among adults. Based on our studies, our immunity level is in the high 90% levels among the older adults.

Dr Chia also asked about the reasons why some of them did not go for vaccination. The factors are quite varied. A large majority of them were just passive, waiting for the next convenient occasion to bring their children for vaccination. Unfortunately, sometimes that occasion never came. They hope that the next time when they see a doctor, they can bring their children, but their children stayed healthy, so never had a chance to see the doctor. When they do see the doctor, the children may be unwell and, therefore, not suitable for vaccination. Therefore, we would like to encourage parents, if possible, to bring your children for vaccination as soon as possible. HPB does conduct vaccination programmes in the schools to provide convenience for parents to have their children vaccinated.

Dr Chia also asked about potential actions against parents whose children are not vaccinated. We are looking into various possibilities, even at the pre-school level, on how we can encourage and ensure that our children who go to pre-schools are vaccinated. Because this is important, not only to protect the individual children but also to protect children who could not be vaccinated. Especially in the infant care, many of them are below 12 months of age and they could not be vaccinated. Therefore the older children ought to be vaccinated to protect them. At the same time, we are also looking at workers in the pre-school sector to ensure that they are covered by vaccination or they have immunity, so as to protect the children under their charge.