As swine flu ramps up in Ireland, what steps can we take to make sure our immune systems are ready? CLAIRE O'CONNELLinvestigates
IT WAS bound to happen – the influenza A H1N1 virus has started to rapidly gain ground in Ireland.
A surge in reported cases last week means “swine flu” is back hogging the headlines, and health authorities here anticipate the virus will continue to spread and cause illness over coming weeks and months.
No vaccine is available yet, and the official line is that anti-viral medication like Tamiflu is to be used only in severe cases, or where there is an underlying condition that could cause complications.
So it’s hardly surprising that DIY immune-boosters and remedies to counter viruses are now exciting interest.
The internet in particular is replete with lists of kitchen-cupboard anti-virals, including lemon balm and green teas, garlic and even plain old apple juice.
Meanwhile in the US, the Food and Drug Administration (FDA) has been actively clamping down on websites selling products with unvalidated claims that they protect against H1N1 – they include a shampoo, essential oil inhalers, protective gloves, various supplements and an electronic instrument offering “photobiotic energy” to strengthen the immune system.
So are there any scientifically proven ways we can help bolster our body’s defences in preparation for exposure to swine flu?
“There is a lot of nonsense out there, but there is also some good science,” says Luke O’Neill, professor of biochemistry at Trinity College Dublin.
Top of his list of anti-H1N1 strategies is avoiding infection in the first place, and our behaviours can help stop the virus spreading.
“It’s the usual thing like washing your hands – it seems very trivial but general hygiene is important. And if someone is infected they have got to stay home,” he says.
But if H1N1 comes knocking, it’s your immune system that will answer the call, and again how we live our lives can affect our immune response.
“We have survived with viruses for millions of years because we have a very effective immune system, so the question is how do you keep that immune system going, and general things like good health will do that,” says O’Neill, who has done research on how the immune system is spurred into action.
Malnutrition, obesity, alcohol, certain diseases and medications and going short on sleep can compromise your immunity, he explains, and there’s also evidence that ongoing stress can weaken your defences.
“Low-level stress can have an effect on the immune system and that’s probably down to the hormone cortisol, which is made during stress and is a well known inhibitor of the immune system.”
But, on the bright side, studies also suggest that keeping a good humour can give your immunity a helpful shot in the arm, according to O’Neill.
“Reasonably credible research over the last couple of years has shown that a happy state gives rise to a better immune system and they can measure that quantitatively,” O’Neill says.
One experiment divided participants into “glass half full” and “glass half empty” dispositions on the basis of brain scans, and found that optimistic people had a four-fold stronger immune response to a flu vaccine, explains O’Neill.
Meanwhile, people watching a funny film have been found to have increased levels of virus-busting cells in their blood compared with those who watched a more mundane movie.
The effect could be down to laughter producing more immune-boosting endorphins, which are also released when we exercise, he suggests.
However, the science is less encouraging about one of the most popular home remedies for fighting viruses: vitamin C.
“There have been many trials on it since the 1970s and no worthwhile effect has been shown,” says O’Neill, who notes that Nobel laureate Linus Pauling’s endorsement of the vitamin fuelled much investigation into whether it could really help protect against viruses like the common cold.
“People tried very hard to show an effect for vitamin C and they couldn’t find it,” he says.
“The best trials were done with identical twins in the same environment: they gave one vitamin C and one didn’t get it, then they looked at infections over the following months and there was no difference.”
The dietary mineral zinc has also been hailed as an immune-booster, but O’Neill argues that we don’t tend to run short on it here.
“The society we live in is overnourished, it would be hard to find zinc deficiency in Ireland – so will taking [high] concentrations of it make a difference is the question, and there’s very limited evidence for that.”
Nor does he see evidence for anything more than a marginal effect of probiotic drinks marketed as immune-boosters. “They are harmless I suppose, you are just paying money,” he says.
However, the herb echinacea has fared better as an anti-viral agent in scientific tests, although its exact mechanism remains unknown and there’s no evidence for any effect against swine flu, according to O’Neill.
“The bottom line is that there does seem to be an effect and it suggests it speeds up your immune response.”