I am writing this at 38,000 feet, passing over the coast of Labrador on the way to Chicago. As I have been in the air for six hours already, it is time to reflect on how well the frequent-flyer health tips are working out.
Admittedly, I started with a handicap. Forty-eight hours before flying, I developed a head cold, which explains the ear pain I have experienced since taking off from Heathrow. As my sinuses are full of fluid, the Eustachian tube which connects the middle ear with the back of the throat is blocked. This means I cannot equalise the air pressure between inside and outside. The trapped air is causing pain and, as it expands, I run the risk of perforating an ear drum.
I have tried to walk around as much as possible, but the Airbus is not as roomy as the older Jumbo jets I have been on before. So I have had to rely on raising my thighs from the seat by means of a cushion in an effort to decompress the leg veins so as to avoid the most serious risk to the modern air traveller; the development of a deep clot in the leg. Doing regular foot exercises helps also.
However, in my rush to get away, I forgot to take a dose of aspirin the day before flying, which is a good preventative measure for anyone who is not allergic to the blood-thinning agent.
I had phoned the airline to try to pre-book a seat as near the front of the aircraft as possible. But so had most of the other passengers, so it was row 64 for me. Possibly the worst place on the aircraft is the back, which is where I found myself sitting, beside an equally disgruntled American of six foot six inches.
Frequent travellers have realised that air quality on modern aircraft deteriorates significantly as you move towards the rear of the cabin. Paradoxically, as Airbus and Boeing develop airplanes which can fly further and more efficiently, the standard of air circulating at altitude has deteriorated sharply. The older Jumbo jets are actually healthier to fly in because fresh air is circulated throughout the cabin. More modern jets re-circulate the same air, which gives the airlines a two per cent fuel bill reduction.
I have been seeing an increasing number of patients with respiratory problems in the week following air travel. Viral upper respiratory tract infections are especially prevalent, which seems to be linked to poor air quality as well as low humidity in the cabin.
The big worry for me is the increasing incidence of TB worldwide. The World Health Organisation is predicting seven million new cases per year. The Centre for Disease Control in Atlanta, Georgia has shown that TB can infect through prolonged exposure to droplets dispersed through the recycled air in aircraft.
A recent case proves the practical implications of the research. Two Scots who flew to New York via Brussels developed multiple drug resistant TB. They had been infected by a female passenger sitting 13 rows away.
I had thought of bringing a surgical mask with me, but according to the director of the Aviation Health Institute in Britain it would not be effective. The AHI has developed a facemask especially for bad air on planes. It can be reused and costs just £10. If you are keen to try one out on your next trip, then telephone 0044 800 6066 to order.
A slightly more expensive, and scientifically unproven gadget is the Ionic Breeze Personal Air Purifier and Humidifier. With a name like that, it has to be American. The device is compact - it looks like a small pair of binoculars or a personal stereo and is worn around the neck.
Whatever about the ionising effect of the gadget, I'm prepared to accept its humidifying benefits. By moistening dry aircraft air as it heads for your nose and mouth, the mucus membranes will become more efficient at repelling the circulating microbes.
Lack of oxygen also contributes to jet-lag, leading to poor productivity. The Institute of Aviation Medicine in the UK has shown that this results in poor work performance due to impairment of mental faculties. Dehydration also contributes to this effect, so plenty of non gaseous and non alcoholic liquids are a must.
Thanks to Brian Doyle for information on the air purifier and AHI face-masks. Any other tips for improving in-flight health to mhouston@irish-times.ie, or leave a message on 01-6707711, ext. 8511.