Vaccine Reactions in Children

( “There’s been a lot of focus in the past week on what we call “febrile convulsions” – a phrase that is probably new to most people, but which describes something which happens to about 3-4% of children under the age of 5. When they get a high fever – for whatever reason – those children have convulsions.

“Febrile convulsions can be alarming for parents, and if they persist can result in a brief admission to hospital. Parents need to keep their children safe during any convulsion. But febrile convulsions do not cause long-term harm, and it is extremely uncommon for them to prove life threatening.

“We’ve received reports about five incidents of febrile convulsions this year among children under the age of 5 years within 24 hours of getting a flu vaccine – four for the seasonal flu vaccine, one for the H1N1 swine flu vaccine.

‘That number will inevitably go up due to publicity around this issue – as health professionals and families report convulsions which may have occurred weeks or even months ago but which they did not feel needed to be reported at the time, or were unaware that they could report this to the Centre for Adverse Reactions Monitoring.

“It’s important for all parents to know that febrile convulsions in under-5s can occur for lots of reasons – they are one way that certain children react to a high fever.

“In Auckland for example, in an average month around 40 to 50 children are brought to hospital Emergency Departments with febrile convulsions – about half of these at Starship and the other half at KidzFirst.

“Some other cases of febrile convulsions are dealt with at a GP’s clinic, in primary care, or in the home – and those do not show up in the hospital figures.

“In looking at the data available to date, it does not appear that there has been any increase in the total number of under-5s hospital presentations in Auckland for febrile convulsions in 2010, compared to the corresponding months in recent years.

“All of the evidence which I’ve seen to date indicates that there has not been a sudden wave of febrile convulsions – or as far we can tell any perceptible increase in the overall rate of febrile convulsions occurring.

“Another way we look at reactions to a vaccine is by seeing how many people go back to their GP or family doctor within three days of receiving a vaccination. Once again, by that measure there does not appear to be any difference between the number of people who return to their GP after receiving the 2010 seasonal flu vaccine, and the rate of re-presentation to GPs for other vaccines in previous years.

“Fever is a common reaction to an immunisation – it shows the immune system is working. In most instances that reaction takes the form of a slightly raised temperature and perhaps feeling a bit off-colour. Only a small fraction of those people go on to develop “a high fever” – the sweaty disoriented state most people think of when they hear the word fever.

“The Ministry of Health’s advice for New Zealand remains the same as it was on Friday last week: People, including children under 5, at risk of increased complications from flu should get a flu vaccine.”

Media Release 30 April 2010 from Ministry of Health’s Chief Advisor on Child and Youth Health, Dr Pat Tuohy.