When three-year-old Jacob's mother asked me recently whether she should take her son round to a friend who had chickenpox, so that he could catch the illness and get it over with, I told her I thought it was an excellent idea. Chickenpox is a mild illness that we all have to catch at some time, so if now is convenient, then go for it.

When I was a child in the 1960s, measles parties were fashionable; we all caught measles and it suited parents to have some control of when they would have to spend ten days nursing their unhappy child. These days, chickenpox parties have taken their place.

Chickenpox and measles are both suited to parties because they are easily recognisable: the blisters of chickenpox and the darkening rash and sticky eyes of measles. Though encouraging children to catch mumps or German measles from an infected child may be a good idea, it is less likely to work, because the diseases are often so mild that they pass unnoticed.

My sister – an experienced nurse - took her son, James, 3, and his best friend Anna, 4, to see their neighbour Kate, who had chickenpox. This was so both James and Anna could catch it at the same time and their mothers could share the childcare.

The children were all encouraged to drink through Anna's drinking straw and the plan worked – both James and Anna caught chickenpox.

However, our view of chickenpox as a harmless illness was challenged by doctors last week, when a call went out for all children to be vaccinated against it.

The doctors had searched out all children who had been admitted to hospital with serious complications of chickenpox; in a 13 month period they found a total of 112 children in the whole of the UK and Ireland .

Most of these had fully recovered by the time they were discharged. However they found six deaths that were due or, the doctors say rather confusingly, possibly due, to chickenpox.

But when we look more closely at these children who tragically, and unusually, died, we find that one did so in the womb, and four out of the remaining five had a serious medical condition such as HIV or cerebral palsy. Only one of the children who died had been in good health – out of a total childhood population of over ten million.

There are other reasons to question the chickenpox vaccine.

Using it will simply shift the age at which people get the disease from young children, to teenagers and adults as their childhood immunisation wears off. (We have already seen this happen with mumps.) This is a problem because the older you are when you get it, the more serious it can be: an adult over 50 is one hundred times more likely to die from chickenpox than a child.

Another problem is that vaccinating against chickenpox will increase cases of shingles, a disease caused by the same bug that is more serious and causes more suffering and death.

The number of children under 10 getting shingles in the USA has doubled since they started vaccinating against chickenpox.

As if that were not enough, we know from experience in the USA , where the vaccine was introduced in 1995, that vaccinated children sometimes develop chickenpox themselves and can occasionally even pass the disease on to others; in one case a pregnant mother had to have an abortion after catching chickenpox from her vaccinated child.

I spent five years researching a book on childhood immunisation and discovered that vaccines often receive less scrutiny of their safety than drugs and other medicines. How can we be sure that a chicken pox vaccine will be any different?

Furthermore, babies already receive 25 vaccines before the age of 15 months. If the chickenpox vaccine is introduced, it is likely to be added to the controversial MMR vaccine. Those of us who have concerns about the cocktail of three live vaccines in the MMR can only shake our heads in disbelief at proposals to add the live chickenpox vaccine to the mix.

There is a case for vaccinating children with serious medical conditions who are more likely to suffer complications, but it makes no sense in healthy children.

So I shall risk the wrath of my colleagues by encouraging mothers to take their children to chickenpox parties. They can then catch the disease at an early age when complications are most unlikely, and they will have lifelong protection, which they won't get from the vaccine.

This does require a commitment to nurse the child through a period when they may be unwell. Not such an easy thing to commit to in this time-pressed society when many parents work, but I believe it is the sensible choice.

Dr Richard Halvorsen is a GP and the author of The Truth about Vaccines (Gibson Square Books)