Doctor warns of complacency in face of autism danger

PUBLISHED : Saturday, 23 April, 2011, 12:00am
UPDATED : Saturday, 23 April, 2011, 12:00am


Hong Kong has escaped the anti-MMR childhood vaccine movement - linking the jab to autism - which spread across many English-speaking countries in the past decade.

But despite the overseas movement's dangers and the fraudulent study that inspired it, a prominent paediatrician has nevertheless warned that local parents are too complacent about potential environmental factors that could trigger the onslaught of autism among some young children.

'They just don't know about it. They are just ignorant about it,' said Dr Wilson Fung Yee-leung, who is a council member of the Hong Kong Medical Association.

He said it was dangerous not to be concerned about autism and its potential environmental causes.

But Fung is in a minority of local doctors who think the commonly administered measles, mumps and rubella triple vaccine could be harmful for children who exhibit risk factors for developing autism. Furthermore, he conceded: 'MMR is doing more good than harm on the whole.' All three diseases may lead to the serious condition encephalitis, which is swelling of the brain.

In the last decade in Hong Kong, MMR coverage for children rarely fell below 99 per cent. By contrast, the vaccination rate in the UK was 92 per cent before the link to autism was made, and plummeted to a low of 79 per cent in 2004. Vaccinations had previously eliminated measles in the UK, but by 2006 it had its first measles death in 14 years.

He said the key was to identify children who might be vulnerable to developing autism and taking precautions. For example, children who have siblings with autistic features are more likely to develop autism.

Fung said for children who have poor immunity or who show adverse reactions to other vaccines, their immune systems can be improved before administering MMR. 'We try to be more cautious for this group. We can do something to help these kids to minimise the risks and to get the benefits out of MMR.'

The controversy over MMR started in 1998 when medical researcher Dr Andrew Wakefield and his team penned a study showing a link between the MMR vaccine and autism. It spurred a groundswell of controversy that led to a dramatic decline in MMR vaccination rates.

The study was discredited last year by the UK's General Medical Council, ruling the researcher acted 'dishonestly and irresponsibly'.

Since its publication, the paper has suffered heavy criticism from the medical community for its unethical recruitment of test subjects and conflicts of interest.

Last year, the Lancet medical journal, where the study was originally published, issued a full retraction in response to the medical council's ruling. In January, the British medical journal BMJ called Wakefield's study an 'elaborate fraud' that damaged public health in the long term.

Yet amid confusion in the West over the vaccine's safety, Hong Kong's MMR vaccination rates have remained consistently high. The Department of Health reports 99 per cent MMR coverage for children born here between 2003 and 2006. The government recommends the first dose of MMR at age one, and the second dose during Primary One.

'I think we are very fortunate our uptake rate remains at such levels,' said Dr Lam Tai-pong, a professor of family medicine at the University of Hong Kong. 'I think we should be proud of ourselves, because it's been proven beyond doubt that it does offer significant protection against these three very serious diseases.'

Public concern over MMR and autism is vastly greater in the UK, where news about the controversy is regularly on the front page.

Wakefield's fraudulent findings were widely publicised in the UK at the time, triggering a decline in vaccination rates. In 2008, the number of measles cases was high enough for the British government to declare the disease 'endemic', meaning it exists within the population. Cases of mumps have risen to epidemic levels, resulting in two deaths.

No other country has experienced a drop in vaccination as dramatic as the UK, but the trend has been felt with measles outbreaks in European countries and the US. The US Centres for Disease Control and Prevention reported that the US population experienced more cases of measles in 2008 than any year since 1997.

But to Wakefield's supporters, the debate is not over. They characterise him as a crusader, one of the few willing to acknowledge the potential problems with vaccines. One of his most high-profile supporters is US actress Jenny McCarthy, who says vaccinations led to her son's autism.

But mainstream medicine subscribes to scientific proof, and there is not enough to link MMR and autism.

'The evidence is not there. I think we have to believe in evidence - that's what the practice of medicine is all about in 2011,' Lam said.

He said Hong Kong parents were more willing to accept the recommended vaccinations for their children because people here tended to follow doctors' orders rather than question them.

'In my practice in Hong Kong, my patients will say: 'Whatever you say; you are my doctor.''

He said the Hong Kong public had a tradition of following authority, part of the Asian culture of conformity. Doctors are also highly respected for their expertise. 'That is an advantage for us practising in Hong Kong. I consider it a privilege, too, because it's not the same in other countries.'

Lam said the prevalence of autism is generally considered to be lower in Hong Kong than Western countries, which might also explain why there was lower awareness about Wakefield's study here.

But Fung, the paediatrician, said people here were less concerned about medical issues because medical services were cheap. But in a country like the US, the high cost of care encouraged the public to pay more attention to their health.

He said the intensity of Hong Kong's work culture distracted people from other issues.

'If they have some time left they'd rather watch a movie or something more relaxing, rather than going after hard stuff like health issues, books, information,' he said.

Sure shot

In the last decade, the percentage of Hong Kong children getting MMR jabs rarely fell below: 99%