Health Advice for Travellers: Staying Safe During Your Trip

Article by: Dr Ooi Poh Siang, Family Medicine Specialist

01 December 2025

Holiday shiok, but health cannot take holiday!

Travelling can be exciting, but it also exposes travellers to different environments, climates, foods, and health risks. With proper knowledge and preparation, most travel-related illnesses can be prevented. This article summarises key health precautions travellers should follow during the journey and at the destination.

1. During the Flight

Cabin Pressure and Dry Air

Commercial airplanes are pressurised to the equivalent of being 2,000–2,500 metres above sea level. Most healthy travellers feel normal, but those with certain medical conditions may experience symptoms due to the lower oxygen level. These include:

Anaemia
Chronic lung or heart disease
Previous stroke
People who normally require home oxygen

Cabin air is also very dry. This can cause irritation of the eyes, nose, and throat. Drinking water regularly and using eye drops or saline nasal spray can help reduce discomfort.

Reducing the Spread of Infection

Respiratory infections such as influenza can spread easily in crowded areas like airports and inside aircraft, especially during boarding and after landing.

Travellers should:

Wash hands frequently with soap and water
Use hand sanitiser with at least 60% alcohol when soap is not available
Avoid touching surfaces unnecessarily
Wear a well-fitting mask (e.g., N95) in crowded or enclosed areas
Cover the mouth and nose when coughing or sneezing
These steps help reduce the risk of catching or spreading respiratory illnesses.

Preventing Deep Vein Thrombosis (DVT)

Long periods of sitting can increase the risk of blood clots in the legs (DVT) or lungs (pulmonary embolism). This risk is higher in travellers with:

Previous DVT or pulmonary embolism
Cancer
Recent surgery
Pregnancy or postpartum
Hormonal therapy
Obesity
Older age
Limited mobility
Blood clotting disorders
Very short or very tall travellers may also have increased risk due to seat height and reduced legroom.

To reduce the risk of DVT:

Choose an aisle seat when possible
Stand up and walk around every 1–2 hours
Perform calf and ankle exercises while seated
Wear graduated compression stockings
High-risk travellers may need medication (to be discussed with their doctor)
Drinking water is helpful for comfort but does not specifically prevent DVT. Avoid excessive alcohol as it may worsen dehydration and reduce movement.

2. Food and Water Safety

Food and water can carry harmful germs in many parts of the world, especially where hygiene and sanitation are uncertain. Travellers should be careful when choosing what to eat and drink.

Food Safety Tips

Avoid:

Raw or undercooked meat, seafood, or eggs
Unwashed fruits and vegetables
Food prepared in visibly unhygienic environments
Certain tropical fish may contain toxins that remain even after cooking

Drinking Water Safety

Contaminated water can cause diarrhoea, vomiting, and other infections. Only use:

Sealed bottled water
Boiled, filtered, or properly disinfected water
Safe water for brushing teeth, preparing food, and making ice
Hot drinks made from freshly boiled water (like tea or coffee) are generally safe

Recreational Water Safety

Swimming in contaminated rivers, lakes, beaches, or poorly maintained swimming pools can cause infections affecting the stomach, skin, ears, or eyes. Even clear water can be contaminated. Good hand hygiene is one of the best ways to prevent illness.

Wash hands:

Before eating or preparing food
After using the toilet
After touching animals
After caring for someone who is unwell
Hand sanitiser is useful when soap is not available, but it is less effective for certain germs, especially when hands are visibly dirty.

3. Sun Exposure

Travellers often spend more time outdoors and may visit places with stronger sunlight, especially near the equator, at high altitude, or between 10 a.m. and 4 p.m. Some medical conditions, such as lupus, can make people more sensitive to sunlight.

How to Protect Yourself from Sunburn

Avoid direct sun exposure between 10 a.m. and 4 p.m.
Stay in shaded areas whenever possible
Wear long-sleeved clothing and a wide-brimmed hat
Use sunglasses to protect the eyes
Apply broad-spectrum sunscreen with SPF 30 or higher and reapply regularly

Sunburn is common but preventable with proper protection.

4. Heat and Cold Illness

Heat-Related Illness

Heat exposure can cause a range of conditions:

Mild: heat cramps, dizziness
Moderate (heat exhaustion): tiredness, dehydration, irritability, confusion
- Treatment: rest in a cool place and drink fluids containing salt and sugar
Severe (heat stroke): a medical emergency
- Requires rapid cooling and immediate hospital care

Prevention:

Stay well hydrated
Avoid heavy activity in extreme heat
Seek shade and take regular breaks
Wear light, breathable clothing

Cold-Related Illness

Hypothermia occurs when the body temperature falls below 35°C. Early symptoms include feeling very cold and shivering. Severe symptoms include confusion, clumsiness, and unconsciousness.

Other cold injuries include:

Trench foot: caused by prolonged exposure to cold, wet conditions
Chilblains: painful or itchy red-purple spots on fingers, toes, or ears
Frostbite: freezing of the skin and deeper tissues, which may cause permanent damage

Prevention:

Keep the body warm and dry
Wear proper cold-weather clothing
Use layers to trap heat
Seek shelter early in extreme cold

5. Marine Animal Hazards

Water activities such as swimming, snorkelling, or diving may expose travellers to marine creatures like jellyfish, corals, and hydroids. Box jellyfish, common in some Malaysian waters especially from October to June, can cause severe pain, collapse, dangerous heart rhythms, or even death.

If stung:

Rinse the affected area with plenty of seawater
Remove any tentacles using seawater, tweezers, or the edge of a plastic card
Do NOT use fresh water, as it may worsen the sting
Vinegar may help inactivate stingers for some Indo-Pacific species
Apply ice packs for mild pain
Avoid home remedies such as alcohol or urine
Seek immediate medical attention, especially if a box jellyfish sting is suspected

Conclusion

Travelling is enjoyable, but it is important to prepare well to stay healthy. Getting a proper check-up, taking the recommended vaccines, and planning your safety steps can prevent many problems. During your trip, simple habits like keeping clean, eating safe food and drinking clean water will help protect you. After you return, watch for any symptoms and see a doctor if you feel unwell. With good preparation and basic precautions, you can travel safely and enjoy your journey with peace of mind.

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