Summer's not quite over yet. If you're jetting off before the season winds down, it's worth clearing up a few travel health myths you might have come across.
Some are fairly harmless. Others can leave you unprotected against genuinely serious risks, like malaria and dehydration. Here are five myths worth setting straight before you head off.
Myth 1: You only need to take anti-malaria tablets while you're actually abroad
This one catches out more travellers than you'd think, and it's a serious mistake. Malaria parasites can still be developing in your body after you've left a risk area. That's why most antimalarial tablets need to be continued well after your return flight.
Exactly how long depends on your tablet. Malarone (atovaquone and proguanil) needs to be taken for seven more days after you leave the risk area. Doxycycline and mefloquine (Lariam) need a full four weeks.1 That's because Malarone also works on the parasite's early stage in your liver, while the others only act once it reaches your blood.
Malaria symptoms can take anywhere from a week to several months to appear, and occasionally even longer. If you feel unwell within a year of coming home, tell a doctor about your travel, even if you finished your course exactly as prescribed.1
Fever, sweats or flu-like symptoms after a trip to a malaria area need urgent medical help. Make sure you say where you've been.
Not sure which antimalarial suits your trip? Our guide to choosing the right antimalaria tablet is a good place to start, ideally a few weeks before you fly.
Myth 2: Mosquito bites are only something to worry about after dark
It's true that Anopheles mosquitoes, the type that spreads malaria, mostly bite between dusk and dawn. But that's not the whole story. Several other mosquito-borne illnesses are spread by mosquitoes that are just as happy to bite in broad daylight.
Aedes mosquitoes spread dengue, Zika, chikungunya and yellow fever. They're usually most active in the early morning and late afternoon, so you'll need to guard against bites throughout the day, not just at night.2
These day-biting mosquitoes also tend to breed close to where people live, in flowerpots, buckets and other small pools of standing water around buildings. So you can be bitten before you've even left your accommodation.2
That means repellent (ideally 50% DEET), covered skin and mosquito nets all matter, whether you're heading out for breakfast or an evening walk. If you're travelling somewhere with malaria, keep taking your prescribed antimalarial tablets too.1
Wearing sun cream as well? Put it on first, then apply your repellent on top.
Myth 3: Sticking to bottled water means you won't get traveller's diarrhoea
Traveller's diarrhoea affects an estimated 20 to 60% of people visiting higher-risk destinations. The cause is usually bacteria, a virus or a parasite picked up from contaminated food or poor hand hygiene, not just the water.3
Bottled water is a sensible precaution. But there are plenty of other ways local tap water can reach you, like ice cubes, or salads and vegetables washed under the tap.
Peel it, cook it or leave it. A simple rule for fruit, salads and street food.
Undercooked food and buffets left out too long are common culprits too, especially in hot, humid climates where bacteria multiply faster. So is not washing your hands before you eat.3
Most cases settle on their own within three to five days with rest, fluids and a rehydration sachet such as Dioralyte. See a doctor if it lasts longer than five to seven days, or comes with a high fever, blood in your stools or signs of dehydration.3
Myth 4: Jet lag will just sort itself out if you get enough sleep
Jet lag isn't just tiredness that a long sleep can fix. It happens because your body clock is out of sync with local time, and extra sleep alone won't reset it.
There's evidence that melatonin can ease jet lag symptoms. It can also help you recover around a day to a day and a half sooner after crossing several time zones.4
The effect tends to be stronger when you travel east. Your body finds it harder to move its clock forward than back, which is why one direction of a trip often feels easier than the other.4
The usual approach is one 3mg tablet at your normal bedtime once you've arrived, for up to five nights. Do not take it earlier than 8pm or later than 4am local time.4
Melatonin can make you drowsy. Do not drive or use machinery if you feel sleepy after taking it.
Melatonin tablets are available from Pharmica after a short online consultation. They work best alongside the basics: staying hydrated, getting daylight at the right times and going easy on alcohol on the flight.
Myth 5: Only older travellers need to worry about DVT on flights
Deep vein thrombosis (DVT) tends to get filed away as something only older travellers, or people with health conditions, need to think about. In reality, sitting still on a long flight is a risk factor in itself, whatever your age or health.
Flights of four hours or more are generally thought to carry a higher DVT risk for any traveller. That's because long spells of cramped sitting slow the blood flow in your legs.5
Some things push that risk higher. These include pregnancy, recent surgery, hormone medicines such as the combined pill or HRT, obesity, and a personal or family history of blood clots. If any apply to you, be extra careful about moving and staying hydrated.5
Get up and walk every hour or so, do simple calf raises in your seat and keep drinking water. Compression socks are widely available from pharmacies if you'd like extra reassurance on a longer flight.
Swelling, pain or redness in one leg after a flight is worth getting checked promptly.5 Our travel health kit guide covers what else to pack for a long-haul trip.
Sudden breathlessness or chest pain after a flight could mean a blood clot has reached your lungs. Call 999 straight away.
Frequently asked questions
Do I need anti-malaria tablets for the whole country, or just certain areas?
Risk can vary hugely within a single country, so it isn't simply a case of "this country, yes" or "this country, no". A pharmacist or travel clinic will look at your exact itinerary, including which regions you're visiting and the time of year, to work out whether antimalarials are recommended and which one suits your trip.
How do I protect myself from mosquito bites during the day?
Use a repellent containing at least 50% DEET, cover up with loose, long clothing where practical, and bear in mind that day-biting mosquitoes often breed in small pools of standing water close to accommodation, not just out in the open.
When should I see a doctor about traveller's diarrhoea?
Most cases settle on their own within three to five days with rest and fluids. See a doctor if it lasts longer than five to seven days, or if you develop a high fever, blood in your stools, or signs of dehydration such as reduced urination or dizziness.
How long does jet lag usually last?
As a rough guide, it takes about one day to recover for every time zone crossed, though eastward travel tends to take longer to adjust to than westward travel. Melatonin can help shorten this for some people.
Is the increased DVT risk only linked to long-haul flights?
The increased risk is generally associated with trips of four hours or more, whether by plane, train, car or coach, so it isn't limited to long-haul flying specifically.
References
- NHS. Malaria: Prevention. nhs.uk
- World Health Organization. Dengue and severe dengue. who.int
- NICE Clinical Knowledge Summaries. Diarrhoea: prevention and advice for travellers. cks.nice.org.uk
- NHS. Common questions about melatonin. nhs.uk
- NHS. Deep vein thrombosis (DVT). nhs.uk
This article is intended for informational purposes only and does not replace professional medical advice. Always read the patient information leaflet supplied with your medication and speak to a healthcare professional if you have specific concerns.