MEDICAL MATTERS:On a typical fortnight trip, travellers lose, on average, three days due to illness, writes MUIRIS HOUSTON.
LAST WEEK’S decision by British Airways and Virgin Atlantic to instruct its check-in staff to look out for passengers showing symptoms of swine flu raises all kinds of interesting questions.
To turn someone away from a flight, based on having symptoms that, in many cases, are indistinguishable from the common cold and other viral infections, is a big step.
Do the airlines have quick access to a medical or nursing opinion beside check-in? Or is this just a form of window dressing, a measure without scientific validity?
During the Sars outbreak in 2003, the island of Taiwan was infected by a single businessman who had flown from Hong Kong to Taipei. This index case caused an epidemic in which 800 people were hospitalised and some 75 died. The episode placed the Taiwanese health system under extreme pressure.
Subsequently, Taiwan became the first country to implement a system whereby travellers arriving at its major international airport have their body temperature measured using infrared cameras.
Unlike symptoms, increased body temperature is a sign that can be measured objectively and non-invasively.
Modern infrared cameras are able to measure differences in body temperature of less than 0.1 degree Celsius. The cameras are programmed to automatically factor in changes of body temperature that are due to environmental factors.
During a 12-month trial, infrared cameras installed at airport arrival gates recognised a body temperature above 38 degrees C in 22,000 passengers.
Dengue fever, imported from abroad, had caused epidemics in Taiwan in the past, so the authorities wanted to see if the detection of an elevated temperature could pick up cases of the disease.
All 22,000 were then assessed by a doctor; in just over 3,000 cases, physicians suspected dengue fever. Subsequent tests confirmed the disease was present in 40 travellers.
A previous programme using questionnaires analysed by airport nurses had for years failed to pick up a single case of dengue fever, so the infrared cameras were a significant improvement.
However, their success depends on the disease being looked for having a relatively high incidence among arriving passengers.
When Canadian and Australian authorities tried a similar approach after the Sars epidemic had peaked, not a single infection was picked up.
Experts reckon temperature screening will work best when there is a significant disease outbreak in the country from which the person has just departed.
The president of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID), Prof Javier Garau of the University of Barcelona, says the current rapid spread of the Influenza
A (H1N1) in the southern hemisphere increases the risk of catching flu “for all Europeans travelling abroad”.
The society released some interesting statistics on travel-related illness recently. It says one-third of European travellers experience travel- related illness.
On a typical two-week trip, ESCMID reckons travellers lose an average of three days due to illness. Of these, almost a fifth remain ill after returning home, while one in 10 require medical care. These figures are higher than I would have expected, based on personal experience.
However, I agree that diarrhoea and respiratory infection are the most common illnesses experienced by travellers during their first two weeks abroad.
“Evidence suggests that factors such as advance booking and the number of hotel’s stars seem to be a protective factor against travel- related infections, as well as sleeping in a single room or drinking mineral water,” ESCMID executive member Prof Robert Read noted.
Illnesses transmitted by ticks have become more common in the past 25 years and may be linked to global warming.
Lyme disease is the most common vector-borne disease in Europe; the ticks that carry the bug are commonly found in temperate, forested areas throughout the continent.
There is no vaccine against the disease. Preventive measures include using insect repellent on exposed skin and checking carefully every day for attached ticks. Ticks can be removed using a tweezers – ideally within 24-72 hours after they have attached themselves, so as to prevent the microbe getting into the body.
There will be a lot of hype around swine flu in the months ahead. But there is no reason for our traditional two-week break from work to become an anxiety-filled fortnight.
Dr Houston is pleased to hear from readers at mhouston@irishtimes.com but regrets he is unable to reply to individual medical queries