Kids flu 'super spreaders' - and why immunisation really matters
The new flu vaccination season is underway, and I've been bracing myself to answer the same questions I answer every year - and bust the same old myths. But this year there is one big difference and that difference is kids.
Three years ago, all two- and three-year-olds were offered a flu immunisation for the first time. Last year, two- to four-year-olds and primary school children in years one and two were added to the list - and this year, all children in years one to three in primary school will be invited too. For children aged two to four, immunisation will be through GP surgeries, while for those in primary school years one to three it'll be via the school.
Before introducing flu vaccination for all children, pilots were run in some parts of the country, with all primary school children offered immunisation. This allowed Public Health England to get a snapshot of what introducing the vaccine might mean in terms of reducing the burden of illness from influenza. Kids are known as 'super spreaders' - they spread the virus around far more other people than adults do. That means immunising them should cut the number of vulnerable adults getting flu complications too - and this theory was borne out in the pilot year.
At pilot sites where all children in local primary schools were vaccinated in the 2014/15 winter there was:
- A 74% reduction in attendances at A&E for respiratory illness amongst primary school aged children in primary school pilot compared to non-pilot areas
- A 93% reduction in hospital admissions due to confirmed flu in primary school age children in primary school pilot compared to non-pilot areas
- A 59% drop in GP consultations for flu in adults in primary school pilot compared to non-pilot areas.
Catching or passing on the flu virus following immunisation is never an issue with the adult flu vaccination, as it doesn't contain any live virus. That means it's impossible for the virus to multiply - and absolutely impossible for it to 'give you flu'.
There are two main reasons people are convinced this happens. Firstly, we give the flu immunisation in winter, when many people are coming down with viruses anyway. If you have the flu immunisation and develop a streaming nose two days later, you may well blame the vaccine even though it would have happened anyway. And secondly, the whole point of the vaccine is to prime your body to fight off the real flu virus if you're exposed to it. This immune process can result in you feeling a bit achey and cold-ey; but this definitely isn't flu either.
I'm often asked about the chance of children who've been immunised infecting others. This is theoretically a risk because it's a 'live-attenuated virus' - the virus that's used in the childhood nasal spray hasn't been killed, but treated to weaken it dramatically. It's been 'cold adapted' - that means that while it can multiply in colder areas like the nose, it can't replicate in the lungs. This allows your child to produce antibodies to help them fight off the real virus, but means they don't get any of the severe symptoms from exposure to the real thing.
In terms of infecting others, you 'shed' much less virus after the childhood immunisation than someone with influenza would. What's more, the virus you do shed can't multiply in the lungs and cause serious infection. The only people who might be at risk are those with a very seriously depleted immune system - such as people who have just had bone marrow transplants. Clearly, children who've just had a bone marrow transplant won't be attending school. And in the USA, where millions of children have been immunised over the last 11 years, there have been no reported problems relating to passing on the infection. To be completely on the safe side, however, a child living in a household with someone in this position would be offered an alternative form of vaccine.
Of course, kids aren't the only ones being invited for immunisation. Other groups are at higher risk of complications such as pneumonia and even death from influenza, and Public Health England is encouraging them to come forward as well. To put the risks into perspective, here's how many times more likely you are to die from influenza that a similar person without a long-term health condition:
- Pregnancy - 7 times more likely (more likely in later stages of pregnancy)
- Heart disease - 11 times more likely
- Lung disease - 7 times more likely
- Liver disease - 48 times more likely
- Kidney disease - 19 times more likely
- Diabetes - 6 times more likely
- Suppressed immune system (cancer, cancer treatment, HIV, treatment for auto-immune conditions, etc) - 47 times more likely
- Multiple sclerosis - 40 times more likely
- Parkinson's disease - 40 times more likely
So there you have it - flu is NOT the same as a nasty cold and it can kill. Getting immunised if you're in a high-risk group can prevent serious complications and even save lives. What are you waiting for?