In many cultures in the past, a baby was not named upon birth but a month or more later, when survival seemed more likely. Infant death, for much of history, was brutally common.

Parents often had to bury a child. In parts of Europe in the 18th century, as many as every third child died. The Victorian poet Christina Rossetti wrote about a painfully familiar tragedy in Baby Lies So Fast Asleep:

Baby lies so fast asleep
That no pain can grieve her;
Put a snowdrop in her hand,
Kiss her once and leave her.

“The Pox” – small pox – was a common killer during Rossetti’s lifetime. Survivors were often disfigured with horribly ugly scars, especially on the face, or left blind. Even in the 20th century, as many as 500 million people died from small pox. Also deadly was diphtheria, recognised by rapid breathing, difficulty swallowing and swelling. Measles made its rounds everywhere – almost every child got the red rash.

Whooping cough was no ordinary cough and lasted months. Violent coughing fits, intense enough to break a rib or cause vomiting, were followed by the suffering child gasping for air in a characteristic “whoop”. Polio left many children paralysed, even quadriplegic, and struggling to speak or breathe, (thus the “iron lung” invention).

In fact, a child surviving childhood without any major disease is a modern phenomenon.

What categorically changed childhood was vaccination. Today, “the pox” is relegated to history, eradicated with vaccination (which ceased in 1977). Polio elimination is probable. Polio cases fell by 99% in the last 30 years. Other scourges of the past are hardly heard of today.

Still, several million young children die annually – about 20 every minute – from preventable illnesses, Unicef (United Nations Children’s Fund) says. Many lack access to immunisation services.

But some have parents who choose not to vaccinate them. Last year in Malaysia, there were 1,500 cases of parents refusing vaccination, the Health Ministry said recently. And in June 2016 , three Malaysian children died from diphtheria.

Knowing the history of childhood diseases, and the colossal impact of vaccination, I find it astonishing that parents would put their child at risk of getting these deadly, crippling diseases.

Because these diseases are out of view, people assume they pose no risk. Not true. Measles cases in Malaysia jumped by 340% in the first week of June compared with the same period last year, a June 27 news report said, quoting the Health Department.

Measles epidemics have surged in Europe. A 2011 outbreak in France spread to 15,000 children. In December 2014, an infected child strolling around Disneyland in the United States led to an outbreak of nearly 100 cases by the end of January. Whooping cough is also back, with 50,000 cases in 2012 in the United States.

While children from severely impoverished families in many parts of Africa and Asia are unable to get vaccines, a vociferous anti-vaccination lobby whipping up fear in the developed world has led to relatively absurd rates of preventable diseases.

Parents are often scared to see a child have any symptoms from a vaccine. But, hey, that’s how vaccines work. A small, weakened sample of the infectious agent provokes the body to produce antibodies and T-cells that remember the disease. Some mild symptoms are normal.

Vaccines are blamed for countless problems – allergies, autism, SIDS, asthma, arthritis…. Polio elimination efforts halted in 2003 in Nigeria after rumours spread that the vaccines were being used to sterilise a community.

The most damaging scare has been sparked by the fear that autism was linked to the measles, mumps and rubella (MMR) vaccine, spread by research involving just 12 children by Andrew Wakefield way back in 1998. He has since been shown to be a fraud who took money for his work. Yet the scare remains.

Public health professionals, who tend to focus on the important stuff like saving lives rather than PR campaigns, have since been forced to spend an awful lot of time and money trying to undo the damage unleashed by Wakefield.

In 1999, a study on MMR and autism was done on 500 children – no connection was found. Another study was done in 2001 on 10,000 children, another on half a million children, and then another … and every time, no connection was found. A 2012 Cochrane Library review of studies covering 14 million children again found, guess what? NO connection. Yet the belief persists. Someone I know recently insisted to me that by “mother’s instinct”, she “knew” the truth.

Anti-vaxxers have a very strong online presence – anyone Googling information on risks will run into their ideas. A new film will no doubt perpetuate this myth.

When parents refuse vaccination, it affects us all. Only when a large proportion of people are immune will the spread of disease stop in the process known as “herd immunity”. For measles, that proportion is 92%; for polio, 80%. Vaccination is a social contract with which we protect each other.

In a world with so many uncertainties and risks, why add preventable diseases to that list? We should be able to kiss our children good night without the threat of deadly diseases looming over us.

Mangai Balasegaram writes mostly on health, but also delves into anything on being human. She has worked with international public health bodies and has a Masters in public health.