World Health Scares:  The Truth (Part 2)

Is it okay to eat EU beef? Are your sperm dying off? Are your fillings killing you? Is your mobile phone frying your brain?

For all the newspaper columns devoted to mercury, mobile phones and mad-cow disease, most of us are still in the dark about the genuine risks. We've separated the certainties from the scare-mongering to unravel the truth about some of the world's biggest health scares. You'll have heard of some of them, others not. But they're all worth knowing about...

The 20th century's worst viral epidemic emerged during World War 1 and by the time it had run its course, 20 million people were dead more than the combined military and civilian fatalities of the war. And while we now have vaccines against flu, the virus, with its many strains, still has the potential to become a lethal epidemic.

1955 POLIO
The first anti-polio vaccine was approved in the US in 1955 but in some cases the vaccine actually triggered the disease. However, today doctors use perfected vaccines and, thanks to intensive international immunisation campaigns, polio myelitis has disappeared from North America and is rare in Australia, and Europe.

1962 DDT
In the early Sixties, US biologist Rachel Carson proved that DDT - an insecticide widely
used around the world - accumulates in the body fat of living beings, passes into the food chain and remains there for decades, causing cancer and adversely affecting hormones and the nervous system. It has since been banned in most countries.

The world's first artificial sweetener, saccharin was developed in 1879. A century later, Canadian scientists found evidence that it might be responsible for bladder cancer in rats. Eight years later, the International Agency for Research on Cancer (IARC) rated saccharin as "possibly carcinogenic to human". Following 11 years of extensive research, the IARC re-evaluated its rating and downgraded the sweetener to "not classified as to its carcinogen city" because humans apparently don't develop cancer in the same way as rats.

ALTHOUGH DEEP-VEIN THROMBOSIS (DVT) has been around for centuries, airlines publicly started paying attention to it in October last year when an otherwise healthy 28-year-old British woman, Emma Christofeersen, collapsed
and died at Heathrow Airport after disembarking from a 20-hour flight from Sydney. Due to the limited leg-room for those in standard seats, the phenomenon was quickly dubbed "economy class syndrome" and remains a real health issue for anyone who flies.

Sitting with your knees bent for several hours can restrict your circulation, causing your blood to suddenly thicken and form a clot in the calf. In your leg, they just cause discomfort, but they can break off and travel to the lungs, causing a fatal obstruction.

Who is most at risk?
Those with a family or personal history of blood clotting; immobilised passengers, such as those wearing a plaster cast on their legs; and anyone over the age of 45. You're 10 times more at risk if you're 75 than if you're 25.

What can you do to prevent it?

The Aviation Health Institute in the UK estimates that four hour or more of idle flying time can cause DVT. It is recommended that you move around, so take a walk up and down the aisle, every hour or so. The following exercises are also recommended:

  • Rest an empty one-litre plastic bottle on its side on the floor. Place your right foot on the bottle and roll over it, alternately touching the floor with your toes and heels and then repeat with your left foot. Try to complete 50 touches as quickly as possible.
  • When the film is about to start, move to the back of the plane and stand on your toes at full stretch, then return to a standing position with your entire foot flat on the floor. Do this until the end of the opening credits and then repeat the exercise in the closing credits, all under the cover of darkness.

John Scurr, a consultant vascular surgeon from University College Hospital in the UK, who is carrying out research on DVT, advises that you drink lots of water to increase blood flow and take an aspirin to thin the blood and prevent it clotting. Also, try to get a seat on the aisle. It means you don't have to clamber over others to get in and out when going to the bathroom.

THE FLESH-EATING Ebola virus didn't earn it celebrity superbug status for the number of deaths in Africa - its 1,200 toll is significant
alongside the millions wiped out by AIDS. Rather, it's feared because of its brutal efficiency if untreated, it has a 60 percent fatality rate. Also, the drugs are very expensive, putting them beyond the reach of Third World medical services. After an incubation period of between three to 20 days, victims fall in and die in a week, racked with fever, diarrhoea and internal bleeding.

Part of the fear about the disease comes from the mystery that surrounds it. When it shows up in the animal kingdom, it's benign; but when it crosses over the humans, it somehow finds a way to the immune system and begins ravaging blood vessels. Researchers have been testing a promising vaccine but, like trials before it, encouraging success rates with lab rats plunged to zero when it was tested on primates. But the search goes on because, even though Ebola's incidence is small scale and isolated at the moment, things could change.

the first recorded infection, AIDS reigns as the world's greatest viral scourge. In Third World Africa, the virus has reduced average life expectancy by 15 to 20 years. Currently, there are 36 million people living with either HIV or AIDS in the world. Infection rates are even rising because young people are becoming complacent about safe sex.

In February, researchers at a US conference announced that the current battalion of AIDS drugs can restore the immune systems of 60 percent of patient. At least 15 vaccines are now being tested, but there are formidable obstacles, most notably the number of strains of the virus - 183. However, researchers believe a vaccine will be found by 2010.

THOSE DISTURBING STORIES about men growing breasts and 10year-old girls becoming pregnant after eating hormone-enhanced meat are true. It's caused by a hormone called DES that's been linked to feminisation in humans. DES was banned in some countries like Australia 30 years ago. However, there are still question marks over its presence in meat from some South- and Latin-American countries.

    Countries like Australia , Canada and the US, still uses a variety of other hormones to improve beef quality (usually to make it leaner), despite the fact the European Union banned them in 1988. The World Health Organisation claims that they mimic naturally occurring hormones and are therefore completely safe in the levels present in beef. But this is disputed by scientists from the European Commission, who insist that oestradio, the mostused hormone, is a catalyst for cancerous tumours.