Growing up in the 1970s, I cannot remember one school friend who suffered from asthma. Now I can count at least three children in a circle of about 16 of my children's friends who have asthma. A straw poll which exceeds the current prevalence: one in seven Irish children suffers or will suffer from asthmatic symptoms. Surveys show the incidence of asthma has doubled in this country in the past 15 years. While there is no known cure, the medical treatment involving the use of preventer and reliever inhalers has become so well established as being effective that it has, perhaps, sidelined other important preventive measures.
Dr Peter Greally, respiratory consultant at the National Children's Hospital in Tallaght, Co Dublin, has recently produced Ireland's first website specifically directed at parents whose children have been diagnosed with asthma. He says this is the most difficult time of year for asthmatics, due to the combined factors of spending more time indoors (thus increasing one's susceptibility to internal environmental allergens such as the house dust mite) and the increased viral infections during the winter months which irritate the bronchial tubes and may bring on an asthma attack.
"This is a treacherous time of the year for children with asthma because the the number of viruses around appear to trigger asthma attacks, particularly in pre-school children. We see a substantial increase in the number of cases admitted to hospital in this age group at this time of year. "We are not sure why this happens, although it may be that the chronic inflammation of the bronchial tubes renders them sensitive and irritable so that exposure to a virus in the upper airways then triggers inflammation," says Dr Greally. This results in wheezing and/or coughing and laboured breathing, all of which are the typical symptoms of asthma which may lead to a more severe attack.
Dr Greally also points to the house dust mite as a trigger which has perhaps, latterly, received less attention than it deserves. "The house dust mite is one of the key factors because in our affluent, Western economies, we live in centrally heated, doubled-glazed conditions with carpets, which is the ideal breeding ground for the house dust mite. For instance, there are several hundred thousand house dust mites on one square metre of carpet."
The significance of the house dust mite lies in the fact that up to 80 per cent of child asthmatics have allergies, and up to 80 per cent of these are specifically allergic to a protein in the stools of house dust mites (there are specific, although not routine, tests available to test this allergic reaction).
So taking measures such as washing bedclothes at 60C (house dust mites are only killed at over 55C), washing favourite bedtime teddies regularly, vacuuming bedrooms twice weekly (ideally, asthmatic children who are allergic to the house dust mite should not sleep in rooms with carpets), damp-dusting bedrooms daily and covering mattresses, duvets and pillows with special barrier covers will, according to Dr Greally, help reduce the numbers of house dust mites and therefore reduce the strength of this particular factor. Allowing fresh air into the house - even in winter - will work against the environment in which the house dust mite thrives. Pet dogs and cats are also not recommended for children with asthma. However, if there are already family pets, they should not be allowed in the asthmatic child's bedroom.
While Dr Greally says that there are no clear urban/rural divisions in the rising figures of asthma, airborne pollution and specifically ozone, nitrogen dioxide and sulphur dioxide have been ruled in as asthma triggers. He points to an Italian study which found that when children with bad asthma were brought to the Alps for several months, upon their return, their susceptibility to the house dust mite had reduced, their bronchial tubes were less irritable and, most significantly, they were able to cut back on their medication. Tobacco smoke is another major asthma trigger, according to Dr Greally.
"Most people realise that women who smoke will give birth to smaller babies, but what they don't realise is that such babies will also have smaller lungs. They might not be allergic but they are more prone to wheezing in the first years of their lives. We are seeing a huge number of small babies admitted to hospital with wheezing illnesses, a percentage of whom will go on to be diagnosed as having asthma," he says. Perhaps we are soon to enter a new era on asthma where, instead of becoming adept at treating it, we will become more adept at preventing its occurrence. This will, according to Dr Ronnie Russell, immunologist and microbiologist at Trinity College Dublin, require us not only to look more closely at our home environment and external pollutants, but also to re-consider the appropriateness of the timeframe in which children are given vaccinations.
"Our knowledge of the immune system is rudimentary but breakthroughs are being made in the whole area of control and regulation," he says. Dr Russell believes the way immune system is treated in the formative years of one's life is crucial to whether an individual will develop asthma or not. Living in an overly hygienic environment and giving very young babies vaccines such as the BCG, can, in his view, cause the immune system to act inappropriately, which may lead to allergic reactions, one of which is asthma.
In their new book, Asthma - The Complete Guide, Prof Jonathan Brostoff, professor of allergy and environmental health and director of the Centre for Allergy Research at University College London, and Linda Gamlin, biochemist and scientific writer, have brought together much of the latest information on asthma and the best way to treat it with and without drugs. They suggest childhood allergies are a fundamental cause of asthma, not just a trigger for attacks, and reducing exposure to the allergen can make a huge difference.
"There is far more that can be done to avoid allergens than most people (including doctors) realise. Don't believe anyone who says `you can't get rid of house dust mites', or `pollen is unavoidable'," write Brostoff and Gamlin. They go on to provide checklists to help parents work out what their child is allergic to.
In a chapter entitled, "The Asthma Epidemic - and How to Beat It", the authors give detailed suggestions on how to reduce the risk of asthma in babies and children. These include many of the aforementioned household adjustments, dealing with damp, mould and/or cockroaches if they are a problem in your home and replacing gas cookers (particularly older models) with electric ones. Frequent courses of antibiotics given to babies under two are also deemed to increase the risk of asthma.
Dr Peter Greally's website for parents of children who have been diagnosed with asthma is at www.asthma-children.com
Asthma - The Complete Guide by Prof Jonathan Brostoff and Linda Gamlin is published by Bloomsbury, £12.99 in UK
