Do planes and trains make us sick?

Poor air quality

When it comes to flying, many of us believe that the air circulating on a plane makes us more likely to catch a cold. However: "There is no evidence to suggest that the air-conditioning on a plane contributes to you getting ill," reassures Dr Eleanor Atkins of Bupa UK. "The air we breathe on a plane, is made up of a combination of fresh and recirculated air, so it's not just recycled air."

However, before you breathe a sigh of relief, there are other ways in which contracting a förkylning or virus might be more likely when travelling. Coming into contact with a large number of people increases your risk of getting sick - as does being trapped in a carriage with them for hours on end. "If you're using a bus, train or plane, there's a higher risk of germs spreading because you're in a confined space," explains Atkins.

"Planes are probably the riskiest form of transport when it comes to spreading illnesses. You'll often be mixing with people from around the globe, bringing you in contact with bugs your immune system hasn't met before," adds Dr Dan Robertson of video consultation platform Push Doctor.

When it comes to transferral of germs, your risk may increase from the moment you enter a station, bus terminal or airport. Touchscreens, check-in desks, door handles and even seat belt buckles can be riddled with bacteria - and as transport hubs are likely to have high footfall, the risk of exposure is increased.

"The bacteria that cause us to get ill can live on surfaces for up to eight hours, and these surfaces can be touched by thousands," explains Atkins. "Surfaces that are handled regularly, like a door handle or a lift button, carry lots of germs because they're used by so many people."

Remember your mum warning you to wrap up warm to keep yourself well? Turns out, she knew what she was talking about. Spending time shivering on a station platform, waiting in a draughty bus station or even feeling the chill of overenthusiastic air-conditioning systems can increase your risk of getting sick - or worsen existing symptoms. "Lower body temperatures may weaken your body's immunsystem, and can help some viruses thrive," says Atkins.

Lack of humidity when flying could also put passengers at increased risk of infection. At high altitude there is less moisture in the air - which could have an impact on our natural mucus barriers, giving viruses a better chance of taking hold.

Often, travelling can mean an early start, crossing to a different time zone or even travelling overnight, meaning we're likely to feel fatigued. This is bad news for our immune system, which can be weakened when we're sleep-deprived, according to a recent studie. This means that even car journeys, where we might feel safe from some of the other risks associated with travel, can make us more susceptible to infection if we disrupt our usual sleep patterns by driving at night.

Cruise ships have come in for a bit of battering in the press in recent years, with outbreaks of stomach bugs such as norovirus seemingly rife. Rather than anything nautical, however, it is the proximity of others, together with large-scale catering and buffet facilities that contribute to this risk.

"When lots of people are together in a confined space, illnesses can spread more easily. It only takes one person working with food to not observe proper hygiene practices, or to continue working whilst suffering from a virus, or returning to work too soon after being ill, to make hundreds of people ill," explains Robertson.

Whether you're nipping into service stations or buying snacks from a vending machine, it's all-too-easy to make poor food choices when on the move. Unfortunately, poor diet "can lead to a detriment in your cellular development, which inevitably increases the chances of catching an illness, particularly if this is a regular habit when you're travelling by car," explains Robertson.

Staying safe

Want to avoid the worst of the travel nasties? Here's how you can keep yourself protected on the go.

Wash your hands

Hand hygiene is key to staying well, so wearing gloves if practical or washing regularly can help. "Germs can get into your body through your eyes, nose and mouth," explains Atkins. "Washing your hands with hot water and soap will remove any germs on your hands."

Use antibacterial gel (but only if necessary)

"If you can't access soap and water, you can use antibacterial gel, but this won't protect you against all illnesses (especially viruses) so there's no substitute for good handwashing, particularly before you have a bite to eat," adds Robertson.

Hold on to your heat

Feeling the chill? It's worth digging out a scarf! "Keeping warm can help you avoid coughs, colds and flu. If it's a particularly cold day, wear a jacket, scarf and gloves. When travelling, try to sit away from any draughty areas, especially for a long journey," explains Atkins.

Eat right

"To try to stay healthy during your journey, opt for a handful of berries and nuts over a bag of crisps. Keeping well hydrated and ensuring fresh air is circulating throughout the vehicle is also important," advises Robertson.

The downside of drink

You know those tempting offers of free alcohol you get when you're flying? They come with a distinct downside. At best, alcohol can exacerbate the effects of jetlag when you're flying. At worst, the combination of dehydration and alcohol fuelled sleep on a plane can increase your risk of deep vein thrombosis, or DVT. So stick to non-alcoholic drinks and get up and walk around the cabin regularly.

Avoid spreading germs

If you are suffering from a cold or virus yourself, protect other passengers by ensuring you catch any coughs or sneezes in a tissue and practise good hand hygiene at all times.