Who's calling the shots?
More parents are refusing to have their children immunised against diseases, but doctors insist vaccinations are essential, writes Elaine Yau
When a baby first comes to the world, painful vaccine shots are among the first things that befall the crying infant. Right after he is born in the hospital, he will get Bacillus Calmette-Guérin (BCG) vaccine against tuberculosis and another one against hepatitis B.
Many more vaccine shots will follow right until the child completes primary school to give him comprehensive protection against a host of diseases. But a growing number of parents have spurned the government immunisation programme, citing health concerns, setting off alarm bells among paediatricians and infectious disease experts.
Although the government says they have not observed any decrease in the immunisation coverage rate among children over the years, paediatricians say there are more parents, especially those returning from overseas, who refuse to get their children immunised.
In 2009, parents set up the Hong Kong Vaccine Awareness League, which now boasts 200 members dedicated to the education of parents and concerned citizens regarding vaccination.
The childhood immunisation programme, launched in the 1960s by the Health Department, targets children from newborns to primary six students. The current schedule covers 10 diseases: diphtheria, hepatitis B, measles, mumps, pertussis, pneumococcal disease, poliomyelitis, rubella, tetanus and tuberculosis.
Disease cases decreased as related vaccines were added to the programme. For example, the hepatitis B vaccine was introduced in 1988; cases decreased from 100 in 1997 to 70 in 2011. Rubella cases dropped from 4,958 in 1997 to 85 in 2011, and measles cases fell from 316 to 12 in the same period. No cases of diphtheria and polio have been reported since 1982 and 1995 respectively.
But the drop has not been sustained for some diseases. From 2008 to 2011, mumps cases rose from 136 to 153, and rubella from 38 to 85. Immunisation rates plummeted after a paper - which has since been discredited - was published in the medical journal The Lancet in 2008 - linking the MMR (measles, mumps and rubella) vaccine to autism.
Following the MMR vaccine scare, measles or mumps outbreaks have been reported in Chicago and San Diego in the US, and in Italy.
Paediatrician Dr Maurice Leung Ping says parents from Britain often prefer their children not to have the MMR vaccine. "Some parents have the misconception that vaccines contain mercury. Although the licensed vaccines are safe nowadays, some parents still do not accept the explanation from the local doctors."
Pertussis, a highly contagious bacterial disease that causes uncontrollable, violent coughing, rarely occurs in Hong Kong, says Leung. But he has diagnosed a few cases, the main source of which being the mainland. "The increased contact between mainlanders and Hong Kong people means we should be on alert," he says.
But vaccines are not without risks and not foolproof. From 5 per cent to 15 per cent of people who get the MMR vaccine will develop a fever.
In the US, 1,000 cases of the inflammatory disorder Guillain-Barre syndrome (GBS) were reported after vaccination between 1990 and 2005, according to a study by the University of Medicine and Dentistry of New Jersey that was published in the Journal of Clinical Neuromuscular Disease in 2009.
GBS causes the body's immune system to attack the peripheral nervous system. Symptoms include weakness or tingling sensations starting in the legs and spreading to the torso and arms in many cases. In severe cases, it can cause total paralysis.
The researchers, using data from the US Vaccine Adverse Event Reporting System, found that most cases (63.2 per cent) occurred in subjects who received the influenza vaccine, followed by the hepatitis B vaccine (9.4 per cent). The remainder were associated with other vaccines or combinations of vaccines. The average age of patients was 47 years.
In Hong Kong in 2010, there were some suspected cases of fetal death after pregnant women were given swine influenza vaccination.
But paediatrician Dr Cheng Man-yung says it's better to have the inoculation than risk the disease, especially as the side effects are usually mild. "The high population density in Hong Kong and frequent international travel means outbreaks of diseases can make people vulnerable," he says.
"The phenomenon of parents refusing immunisation came after unfounded vaccine scares in the West. The growing community of parents who are ardent nature advocates and practise organic and chemical-free living are also to blame."
Leung says misconceptions about vaccines are still widespread among parents: "For example, some parents discredit the influenza vaccine when they see their children develop cold symptoms after the vaccination. But most of the time, people are confusing symptoms of influenza with the common cold."
Vaccination has been successful at eliminating diseases. Smallpox, which has caused widespread epidemics throughout history, was declared eradicated by the World Health Organisation in 1980. Polio, which struck 1,000 children per day in the mid-1980s, has been reduced by 99 per cent worldwide and is now found only in a few areas in Nigeria, Pakistan and Afghanistan.
Financial planner Kay Fung Yin-ha always prepares two letters before her six-year-old son Markus Tsui starts the academic term each year. One is addressed to the Health Department asking for exemption from immunisation. The other is addressed to the school, spelling out her reason for doing so.
"My son has not had even one shot of vaccine since his birth," she says. "When health officials visit the school to immunise children, the teacher shows the letter to them so that my son can be spared."
Fung feels there's no need to subject her child to vaccine for diseases that are no longer found in Hong Kong. She says parents lack information about the content of vaccines to make an informed choice. "Pharmaceutical companies have axes to grind in their vehement push for vaccination," she says.
"Diseases are natural and stir up a child's immunity system. Markus developed rashes before, but he quickly recovered from them."
Beautician Shirley Fu Pui-lam, chairman of the Hong Kong Vaccine Awareness League, says it's irresponsible and immoral to dismiss as alarmist the diseases caused by immunisation.
"Even if just one person fell ill, it still constitutes a risk which merits more research to further prove the safety of vaccines. Tracking studies of over 10 years should be conducted to see whether those who are immunised develop any problems before mass immunisation programmes are promoted."
While the childhood immunisation programme is voluntary in Hong Kong, in parts of the US, Australia, Spain, Greece and Germany parents must provide vaccination certificates before children are allowed to start school. WHO recommends that at least 95 per cent of the population needs to be vaccinated in order to create a herd immunity effect.
A government spokesman says Health Department surveys on Hong Kong children show that coverage rates of vaccines included in the childhood immunisation programme has consistently been higher than 95 per cent. Surveys are done regularly: four have been done between 2001 and 2009, covering those born between 1995 and 2006.
The Children Health Concern Society - which runs the Child Vaccination Concern Group - surveyed 624 families with children under 12 years in 2008. They found that less than half the families had children who received the influenza vaccine. Society convenor Bill Lay says the government should update the childhood immunisation programme to include diseases such as influenza and meningitis.
At present, the government provides free influenza vaccination only for chronic patients in paediatric outpatient clinics, and children aged between six months and six years from families on social security. A government spokesman says the Scientific Committee on Vaccine Preventable Diseases under the Health Department provides science-based advice on vaccine use at the population level. The pneumococcal conjugate vaccine was included in the childhood immunisation programme in September 2009 following the committee's recommendation.
"The committee closely monitors and reviews the latest position of the World Health Organisation on immunisation and vaccination, scientific developments and application of new vaccines, vaccine formulations and cost-effectiveness, changes in the epidemiology of vaccine preventable diseases and the experiences of other health authorities," says the spokesman.
Compulsory immunisation is a contentious issue. Those against immunisation argue they should be given a choice; health advocates say failure to immunise will put the child and the population at risk.
Following the MMR scare, and a resurgence of measles in England and Wales, there have been calls from the health community for the MMR jab to be made compulsory.
In an article published in The Lancet in last year, Adam Finn, professor of paediatrics at the University of Bristol Medical School and Julian Savulescu, bioethicist and professor with the University of Oxford, equate the failure to vaccinate with child abuse.
They wrote: "Some parallels can be drawn between immunisation and child protection. Child abuse and many vaccine-preventable infections are prevalent but are largely invisible or at least not widely known about … There are many challenges [for successful development and implementation of vaccines in the coming decades.]
"For all the recent advances in biomedical sciences, particularly molecular microbiology, immunology and genetics, the biggest hurdle … could relate to failure of parental acceptance of safe and effective vaccination."