Summer's not quite over yet, and if you're planning on jetting off before the season winds down, it's worth dispelling some travel health myths that you may have come across. Some are fairly harmless, but others can leave you unprotected against some genuinely serious health risks like malaria and dehydration.
Here's 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 bloodstream after you've left a risk area, which is exactly why most antimalarial tablets need to be continued well past your return flight.
Exactly how long depends on which tablet you're taking. Malarone and doxycycline need seven more days after you leave the risk area, while mefloquine (Lariam) needs a full four weeks, because it works differently against the parasite's liver stage.1
It's also worth knowing that malaria symptoms can take anywhere from a week to several months to appear, and rarely even longer. If you feel unwell within a year of coming home, mention your travel history to a doctor, even if you finished your course exactly as prescribed.1
If you're 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 species that spreads malaria, do mostly bite between dusk and dawn, but that's not the whole story. Several other mosquito-borne illnesses are spread by species that are just as happy to bite in broad daylight.
Aedes mosquitoes, which spread dengue, Zika, chikungunya and yellow fever, are typically most active in the early morning and late afternoon, and travellers are advised to guard against bites throughout the day, not only 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 end up being bitten before you've even ventured out and explored where you're staying.2
That means repellent, ideally at least 50% DEET, covered skin and mosquito nets matter whether you're heading out for breakfast or an evening walk, alongside taking your prescribed antimalarial tablets if you're travelling somewhere malaria is present.1
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 travelling to higher-risk destinations, and the underlying cause is usually a bacteria, virus or parasite from contaminated food and poor hand hygiene rather than water alone.3
Drinking bottled water is a sensible precaution, but there are many ways that your food and drink can still come into contact with the local water - ice cubes made with tap water, as well as the washing of salads and vegetables under the tap for example. Undercooked food and buffets left out too long are also common culprits, especially in warmer and more humid climates where bacteria can grow and multiply much faster, alongside not washing your hands before eating.3
Most cases settle on their own within three to five days with rest, fluids and a rehydration sachet such as Dioralyte, but 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 simply tiredness that a long sleep fixes. It's a result of your body clock being out of sync with the local time, and extra sleep alone won't reset it.
There's evidence that melatonin can make jet lag symptoms less severe and shorten recovery time by around a day to a day and a half after crossing several time zones. The effect tends to be more noticeable when travelling east, since your body finds it harder to advance its clock forward than to delay it, which is why the flight home sometimes feels easier than the flight out.4
The usual approach is a 3mg tablet taken at your normal bedtime once you've arrived at your destination, not any earlier than 8pm or later than 4am local time, continued for up to five nights.4
Melatonin tablets are available from Pharmica following a short online consultation, and are worth considering on top of the basics: staying hydrated, getting daylight at the right times, and going easy on alcohol in the air.
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 existing health conditions, need to think about. In reality, sitting still for a long flight is a risk factor on its own, whatever your age or health.
Flights of four hours or more are generally considered to carry an increased DVT risk for any traveller, since prolonged, cramped sitting slows blood flow in the legs.6
Certain things do push that baseline risk higher, including pregnancy, recent surgery, some hormone-based medications such as the combined pill or HRT, obesity, and a personal or family history of blood clots, so it's worth being extra diligent about movement and hydration if any of those apply to you.6
Getting up to walk every hour or so, doing simple calf raises in your seat and staying hydrated help reduce the risk for everyone, and compression socks are widely available from a pharmacy if you want extra reassurance on a longer flight. Swelling, pain or redness in one leg after a flight is worth getting checked promptly.6 Our travel health kit guide covers what else is worth packing before a long-haul trip.
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. Travel vaccination advice. 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.