Imagine you've just boarded a four-hour flight. You're settling in with your magazine when another passenger squeezes past and sits down next to you. You can't help but notice they have a chronic skin condition affecting their hands, arms and face. And then they start scratching.
How would you feel?
Dermatologist Kurt Gebauer has a pretty good idea of how most people would feel - they'd recoil and start panicking, or at the very least, feel intensely uncomfortable.
They might glare. They might demand to be moved. They might shift as far as possible in their seat to avoid contact with their neighbour.
Or they might ask intrusive questions or offer unsolicited advice.
"Most people would be horrified for themselves - not for the poor person next door who's got the problem," Dr Gebauer says. "Their first impression is 'Oh my God - what about me? Am I going to catch something?' The thing is - skin conditions are hardly ever infectious. Nothing is going to happen."
Now imagine again you've just boarded a four-hour flight. You squeeze past the person in the seat next to yours and try to settle in.
It's hard though - your chronic skin condition is worse than ever. You're intensely uncomfortable and the itching is driving you nuts. You can't help yourself - you start scratching and the person next to you visibly recoils.
They glare at you and buzz for the hostess. They loudly demand to be moved. Or they stare at you with open curiosity and start asking questions.
How would you feel?
Dr Gebauer has a pretty good idea of how this person would feel, too - he sees this kind of person every day in his dermatology practice, and many of them are wrecks.
They're stressed, not sleeping, teary, not thinking straight - some are even suicidal.
So great is the stigma attached to skin conditions such as acne, vitiligo, eczema, dermatitis or hyperhidrosis (excessive sweating), that people would rather die or hide in their homes than have to keep putting up with being kicked out of pubs or having people refuse to shake their hands, take their money, or look them in the eye.
"They have a bit of eczema, psoriasis, vitiligo - they don't look wonderful and Scandinavian or like the advertising we see," Dr Gebauer says.
"It seems to be hardwired in people's brains - some sort of hangover from the days of leprosy. Rashes and skin problems are still associated with a dirty, grubby person."
He says part of the problem is Western society's obsession with self and perfection, along with a loss of basic compassion and care for others.
The result is often, at best, thoughtless treatment of people with "embarrassing problems" such as skin conditions and, at worst, outright marginalisation - even for conditions as common as acne.
"The most common complaint we would see would be acne which, although it doesn't sound horrible, is probably your number one skin issue with people," he says. "It's probably the main thing we see that people get upset, depressed or suicidal about. It's extremely common.
"There are lots of studies with acne where they have looked at the psychological aspects and how people feel about themselves, and the psychological/psychiatric morbidity is huge."
He says other hard scientific studies have concluded that it's easier to be a parent dealing with a child with leukaemia or kidney failure than it is to care for a child with eczema.
"That's all very hard scientific data that has been studied properly," Dr Gebauer says. "The effect of skin disorders on family in time and effort and all the other bits, in terms of psychology, is quite high.
"It's all to do with things like, if you are a kid with bad skin disease, you're not going to get invited to parties. It starts at that level and just gets worse."
He says the sad thing is that many skin conditions, especially acne, are eminently treatable but sufferers don't always seek help. This may be because they are too embarrassed or else so stressed that they struggle to make rational decisions about treatment.
"Many of these things are pretty easy to fix or improve significantly," Dr Gebauer says. "There are people who get bad skin rashes who for some reason don't want treatment because of the side effects or their beliefs, or they're so emotionally devastated they can't even tell you what day it is. But these days we can make most of these conditions go away.
"What's interesting to me is how people feel about themselves. And why others respond the way they do?
"Why is it that society makes us feel like that?
"And how can we change the hardwiring and stop people from saying 'Oh my God! You look terrible!'?
"That doesn't help anyone."If you or someone you know is thinking of suicide call Lifeline on 13 11 14.
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