How to overcome S'pore parents’ hesitancy over their kids' Covid-19 vaccinations

The Covid-19 pandemic shows little sign of waning as we approach the end of its second year, with the appearance of the highly transmissible Delta and Omicron variants in October 2020 and November 2021 respectively.

Even as we await the results of epidemiological and laboratory investigations on how easily the Omicron variant spreads and the extent that it can evade the immunity provided by vaccination or past infection, it is clear that there will likely be future variants and waves of infections in the near term.

The virus is unlikely to evolve itself into obsolescence, and there is no obvious selection pressure for less virulent variants to emerge.

Against such a backdrop, Singapore’s Ministry of Health has signalled that it will roll out Covid-19 vaccination for children aged five years and above by January 2022.

This has seemed an inevitable move, as Singapore has achieved over 90 per cent vaccination rates for all age groups 12 years and above through a combination of ease of access to free vaccines, public education, outreach, and coercive vaccination-differentiated measures against those who voluntarily remain unvaccinated.

Multiple studies evaluating the cost-benefit of Covid-19 vaccines versus the risk of  infection in young children agree that although the individual benefit of vaccination is lower compared to adults, it still greatly outweighs the risk of adverse outcomes from being infected.

There are other important population benefits too, including indirect protection of vulnerable members of the same household or class as well as potentially reducing the risk of disruptions to face-to-face schooling and other educational activities.

Several Covid-19 vaccines have also been approved for children aged five years and above in many countries, including the Pfizer-BioNTech and Sinovac vaccines that are available in Singapore.

Millions of children aged five to 11 years have already been safely vaccinated in the United States and Israel, with most European countries poised to follow suit later this month.

Yet, anecdotally and based on opinion polls, it is likely that there will be considerable hesitancy among parents to sign up their young children for Covid-19 vaccination.

This might seem surprising considering that Singapore has one of the highest childhood vaccination rates worldwide, with well over 95 per cent of children vaccinated against measles, diphtheria, poliomyelitis and hepatitis B despite the fact that only the first two vaccinations are mandatory here.

However, history shows that immunisation is a social and cultural programme in addition to being a public health measure.

How well a community responds is also shaped by the historical context.

Our high childhood vaccination figures belie the initial difficulty in convincing parents to vaccinate their children decades ago, and it is helpful to revisit the circumstances leading to diphtheria vaccination being mandated here, as well as the reactions thereafter.

A LESSON FROM THE PAST

Diphtheria was one of Singapore’s worst infectious diseases after the World War II (WWII).

The diphtheria vaccine first became available in Singapore in 1939.

Post-WWII, efforts were made to encourage uptake by offering the vaccine free alongside public education, but these were met with lukewarm parental response.

Interestingly, when compulsory vaccination was mooted in 1957, many parents’ thinking was: “If prophylactic immunisation is so effective and not dangerous, why is it not compulsory like vaccination against smallpox?”

In 1961, the Diphtheria Immunisation Ordinance was passed by Singapore’s Legislative Assembly, mandating vaccination for children under the age of one year after years of lukewarm parental response to free voluntary vaccination.

In the lead up to independence and the years that followed, many parents were reluctant to have their children vaccinated because they distrusted biomedicine and its association with colonial rule.

As the British lamented, terminally ill children were being brought to the hospital too late to be saved.

This also stemmed from a long history of Asians in Singapore viewing the hospital as a place of dying.

Even in the initial years of mandatory vaccination for diphtheria, despite the risk of a fine of S$500 (equivalent to more than S$2,000 today) for parents whose child was found to be unvaccinated, public uptake remained low.

In 1971, the Health Ministry announced a new requirement for children who wished to be admitted to primary school — that documentary proof of vaccination for diphtheria, smallpox, tetanus, poliomyelitis and tetanus be produced.

This final measure lifted and kept diphtheria vaccination rates above 90 per cent from 1972 onwards.

That was the challenge Singapore had to tackle as it made the transition from a colony to a nation-state.

People’s anxieties were overcome only by a combination of factors — multiple public health campaigns aimed at parents and proof that vaccines were safe in the long term.

Even then, measures such as linking vaccination to schooling were required to speed up the pace of vaccination and keep vaccination rates high.

It was only in 1975, 14 years after diphtheria vaccination was mandated, that Singapore became free of diphtheria.

How does this history relate to vaccinating young children against Covid-19?

It is clear that parents’ concerns about the Covid-19 vaccines need to be taken seriously, even if the vaccines have already been shown to be safe in adults here and children overseas.

If the aim is to achieve a high vaccination rate among young children rapidly, coercive measures will likely be necessary, and linking vaccination to schooling is the most effective measure historically.

However, such measures — even if vindicated on a public health basis — result in polarisation and will spark greater resentment in the minority who are hesitant about Covid-19 vaccines.

Covid-19 vaccination is also unlike other childhood vaccinations in that frequent repeated boosters may be necessary as immunity wanes and new variants arise.

Based on the history of other vaccines such as the pneumococcal, chickenpox and human papillomavirus vaccines, vaccination rates among children should eventually rise over time in Singapore, even without legal mandates or the introduction of measures linking vaccination to schooling.

The key question is whether there is the luxury of time in the case of Covid-19, given the threat of new variants and the coronavirus’ continued ability to spring nasty surprises around the world.

ABOUT THE AUTHORS:  

Associate Professor Hsu Li Yang is vice-dean of global health and programme leader of infectious diseases at Saw Swee Hock School of Public Health, National University of Singapore. Dr Loh Kah Seng, a historian and founder of Chronicles Research and Education, is researching the history of pandemics in Singapore.