Editor’s Note: This is general travel health advice and is not intended to replace individual advice from your GP, specialist nurse or another qualified travel health professional, that has been tailored to your past medical history, medication or travel plans. This article was reviewed and updated on November 2026. It is routinely reviewed every 3 years unless new clinical evidence emerges.

Taking a gap year is one of the best ways to see and explore the world, but mosquitoes remain an annoying and unfortunate reality of many journeys. As well as leaving you with rage-inducing itchy bites, some mosquitoes can also carry potentially serious diseases such as malaria and dengue fever. Knowing where these diseases are a risk, how to reduce your chances of being bitten and what to do if you become ill is an important part of looking after your health and making the most of your trip.

As a former nurse with a background in emergency nursing and travel and tropical medicine, I have seen first-hand how much confusion there can be around mosquito-borne diseases, including during the ten years I ran my own online travel clinic. And as a backpacker with over 25 years of experience travelling the world, I have also had my fair share of run-ins with those irritating little pests. I even had an unfortunate bout of dengue fever while travelling in India, so I know that getting ill can be a miserable experience, even when you have taken sensible precautions.

But this isn’t something that should put you off travelling or leave you terrified of every mosquito bite. Malaria and dengue are different diseases, and understanding the risks and the simple steps you can take to reduce them will help you prepare for the trip you are taking, recognise when you need medical help and get on with enjoying your adventure.

What Are Malaria And Dengue Fever? Quick Answer

Malaria and dengue fever are two different diseases that can affect travellers and are usually spread through the bites of infected mosquitoes. Malaria is caused by a parasite that infects red blood cells, while dengue is caused by a virus. Both can cause fever and flu-like symptoms, and both can become serious, so it is important to seek medical advice if you become unwell during or after travel.

Your risk will depend on where you go and what you do, but there are practical steps you can take to protect yourself. Avoiding mosquito bites is important for preventing both diseases. Depending on your trip and individual circumstances, you may also be advised to take antimalarial medication or consider a dengue vaccine.

What Is The Difference Between Malaria And Dengue Fever?

Malaria and dengue fever are often mentioned together because both are spread by mosquitoes and can cause similar symptoms, and this can also sometimes cause a lot of confusion between the two. They are, however, different diseases, and knowing the difference can help you understand how to protect yourself and what to do if you become ill.

	Malaria	Dengue fever
What causes it?	A parasite called Plasmodium.	The dengue virus.
How is it spread?	Usually through the bite of an infected Anopheles mosquito.	Through the bite of an infected Aedes mosquito.
When do mosquitoes bite?	Mainly in the evening and at night.	Mainly during the day, particularly around early morning and evening.
How can you reduce your risk?	Avoid mosquito bites and take antimalarial medication if it is recommended for your trip.	Avoid mosquito bites. A vaccine may also be considered for some travellers.
How is it treated?	With antimalarial medicines. Some people need hospital care.	There is no specific medicine that cures dengue. Treatment focuses on managing symptoms and providing medical care when needed.

Although the mosquitoes that spread these diseases tend to bite at different times, this doesn’t mean you only need to protect yourself at certain hours. Taking precautions against bites during both the day and night helps reduce your risk of malaria, dengue and other mosquito-borne diseases.

Understanding Your Risk Before You Travel

The risk of malaria and dengue varies from one destination to another, and it can vary within the same country too. A trip spent in a city may involve different risks from one that includes rural villages, jungle trekking or time in more remote areas. The time of year, the length of your stay, your activities and the places you sleep can all influence your chances of being exposed to mosquitoes.

It is also important to remember that malaria and dengue do not necessarily occur in the same places or present the same level of risk. An area where malaria tablets are not recommended may still have a risk of dengue or other mosquito-borne diseases. Dengue can occur in towns and cities as well as other areas, so urban travel is not a reason to overlook mosquito bite prevention.

The longer you spend in an area where these diseases occur, the more opportunities there may be for exposure, but even a short visit can carry a risk. Equally, an area described as ‘low risk’ for malaria is not necessarily risk-free. The advice may be to concentrate on avoiding bites and being aware of symptoms rather than routinely taking antimalarial tablets.

Look Beyond The Country Name

When checking the risk for your trip, think about the whole route rather than just the countries on your itinerary. A few days in one location followed by a trek or an overland journey through another region may change the precautions you need. Even a stop that feels like a small part of a much bigger adventure deserves a little thought.

Start by checking the current country information and outbreak updates on TravelHealthPro, paying attention to the specific regions you plan to visit. Risk and recommendations can change, so it is worth checking again closer to departure rather than relying on an old guidebook or advice from someone who visited years ago.

Get Advice For Your Specific Trip

A pre-travel consultation can help you make sense of the information and work out what applies to you. Speak to a practice nurse, pharmacist or travel health professional and tell them as much as you can about:

• The countries and specific areas you plan to visit, including stopovers.
• When you are travelling and how long you expect to stay.
• Your planned activities, such as trekking, camping or visiting remote areas.
• The types of accommodation you are likely to use.
• Any medical conditions, regular medication, allergies or previous reactions that may affect your options.
• Whether you have had dengue before.

Your own health and circumstances matter as much as the route itself. They can affect which precautions are recommended and which antimalarial medicines or vaccines may be suitable for you. If you are pregnant, have a weakened immune system or have another condition that could increase your risk of severe illness, make sure this is discussed as part of your assessment.

What If Your Plans Are Flexible?

You don’t need to have every bus journey and hostel booked before asking for travel health advice. One of the joys of backpacking is the freedom to change your plans, stay somewhere longer or follow an opportunity you hadn’t expected. But having a broad geographical plan gives you a useful starting point for preparing for the risks you may encounter.

Start by thinking about the countries and regions you are likely to visit, your probable route through them and the activities you want to do. Then consider the ‘what ifs’: perhaps you might add a jungle trek, cross a border overland or visit a rural area you haven’t yet committed to. You don’t need to plan for every possibility, but identifying the options you are seriously considering will help you prepare for them.

This is where regional risk mapping comes in. Look at the malaria and dengue risks along your likely route and in the areas you might reasonably add to it. This can help you identify where the risks change, which parts of your journey may need different precautions and where you might need to seek further advice before changing direction. Talk through that outline with a travel health professional before you leave, so you can build some flexibility into your plan.

For example, if you may visit an area where antimalarials are recommended, you can discuss obtaining a suitable supply from a reputable UK source before you leave. Where they are appropriate for both you and the destination, medicines such as doxycycline or atovaquone/proguanil are normally started one to two days before entering a malaria-risk area. They must then be taken throughout your time in the area and continued for the prescribed period afterwards, which differs between the two medicines. Your travel health professional can help you plan how and when to take them for your itinerary.

Establishing a strong routine for avoiding mosquito bites from the start is a sensible first line of defence, particularly when you may be moving between areas with different risks. Take an effective repellent with you and think about clothing and sleeping arrangements as part of your preparation. Bite prevention remains important whether or not you need antimalarial medication, and it helps reduce the risk of dengue and other mosquito-borne diseases too.

It is also worth researching where you could get help or replenish supplies along your likely route. Before heading somewhere remote, find out where you could access medical care and how you would get there if you became ill. Consider where you could obtain more repellent or seek professional advice if you extend your trip, and carry enough supplies for the time you expect to spend away from reliable services.

If your plans change significantly while you are away, check the current advice for your new destination and seek further travel health advice before entering an area where different precautions may be needed. Don’t assume that suitable antimalarial medication will be readily available or that you can wait until you arrive to start taking it.

The aim isn’t to plan every moment of your trip around mosquitoes. It is to have a practical plan that gives you room to be flexible, while knowing how to look after yourself wherever your adventure takes you.

Malaria: What Travellers Need To Know

Malaria is a potentially serious infection caused by parasites called Plasmodium. It is usually spread through the bite of an infected female Anopheles mosquito. Once inside the body, the parasites travel to the liver before entering and multiplying in red blood cells.

There are several species of malaria parasite that can infect humans. Some can cause particularly severe illness, while others can remain dormant in the liver and cause malaria to return months or even years later. The type of parasite and how quickly the infection is diagnosed and treated can affect how serious the illness becomes.

Malaria occurs in parts of Africa, Asia, Central and South America and elsewhere, but the risk varies considerably between and within countries. Not every destination has a risk, and not every traveller needs antimalarial medication. What matters is understanding the risk along your particular route and taking the precautions recommended for you.

Malaria can be life-threatening if it is not diagnosed and treated promptly, but it is also preventable and treatable. Knowing how to reduce your risk and when to seek medical help makes a significant difference.

What Are The Symptoms Of Malaria?

The symptoms of malaria can be difficult to recognise because they often resemble flu or other common illnesses. They can include:

• A high temperature, or feeling hot, cold or shivery.
• Sweating.
• Headache.
• Muscle aches and tiredness.
• Nausea, vomiting, abdominal pain or diarrhoea.

Not everyone will experience the same symptoms, and they may not all appear at once. You might initially feel as though you have picked up a minor illness, but malaria can become serious quickly, so it is important not to dismiss symptoms or wait to see if they pass.

Symptoms often begin within a few weeks of infection, but malaria can also develop months after travel and, in rare cases, even later. You may feel perfectly well throughout your trip and only become ill after you have returned home.

You cannot tell whether you have malaria based on symptoms alone. Diagnosis requires a blood test, which is why prompt medical assessment is so important. If you develop a fever or other symptoms during or after visiting a malaria-risk area, seek medical advice urgently and explain where you have travelled. Don’t wait until you get home if you are still travelling, and remember that taking antimalarial medication or not remembering a mosquito bite does not rule malaria out.

How Is Malaria Prevented?

Preventing malaria is not about relying on one tablet or one bottle of repellent. It starts with understanding the risk in the places you plan to visit, then using the precautions that are appropriate for your trip. A useful way to remember the key steps is the ABCD of malaria prevention.

• A is for awareness of risk. Check current advice for the specific areas you plan to visit, not just the countries on your itinerary. A travel health professional can help you understand what the risk means for your trip and which precautions are appropriate for you.
• B is for bite prevention. Use an effective insect repellent, cover exposed skin where practical and think about how you will protect yourself while sleeping. Mosquitoes that spread malaria bite mainly in the evening and at night, but avoiding bites during the day is important too, as other mosquito-borne diseases have different biting patterns.
• C is for chemoprophylaxis. This is the medical term for taking antimalarial medication to reduce your risk of developing malaria. Tablets are recommended for some destinations, but not every trip. If you need them, take them as advised before, during and after your time in the malaria-risk area. The timing depends on the medicine.
• D is for diagnosis. If you develop a fever or other symptoms during or after visiting a malaria-risk area, seek medical advice urgently and explain where you have travelled. This applies even if you took antimalarials. Prompt diagnosis allows treatment to begin as quickly as possible.

Antimalarials significantly reduce the risk of malaria when taken correctly, but no medication provides complete protection. They also do not prevent dengue or other mosquito-borne diseases, so avoiding bites remains important whether or not you are taking tablets.

Equally, if antimalarials are recommended for your trip, mosquito avoidance is not a substitute for taking them. The strongest approach is to use the precautions appropriate for your journey together.

How Is Malaria Treated?

Malaria can be treated with antimalarial medicines, but suspected malaria is a medical emergency and treatment needs to begin as quickly as possible once it is diagnosed. This is why getting a blood test and a prompt diagnosis is so important: the sooner malaria is identified, the sooner the right treatment can begin.

The medicine used will depend on the type of malaria parasite, where the infection was acquired, how severe the illness is and whether you have already taken antimalarials. Treatment may involve a different medicine or dose from the one used to prevent malaria.

Some people will need hospital treatment, particularly if they have severe malaria or are at risk of complications. Others may be able to take their treatment without staying in hospital, following a medical assessment. In either case, it is important to complete the full course and follow the advice given by your healthcare team, even if you start to feel better.

Some types of malaria can remain dormant in the liver and cause the illness to return later. If you have one of these infections, you may need additional treatment to help prevent a relapse.

The reassuring news is that malaria is treatable and most people make a full recovery with prompt diagnosis and appropriate care. The key is not to delay getting help if you become unwell.

Dengue Fever: What Travellers Need To Know

Dengue fever is a viral infection usually spread through the bite of an infected Aedes mosquito. It occurs in many tropical and subtropical regions, including parts of Asia, Africa, Central and South America, the Caribbean and the Pacific. Local transmission has also occurred in some parts of southern Europe.

Dengue can occur in towns and cities as well as rural areas, so you don’t have to be trekking through a jungle or travelling somewhere remote to be exposed. The mosquitoes that spread dengue mainly bite during the day.

Unlike malaria, dengue is not caused by a parasite, and antimalarial medication does not protect against it. Many people who catch dengue have no symptoms, while others develop an illness that can leave them feeling extremely unwell. Most people recover, but dengue can sometimes become severe and potentially life-threatening.

Understanding the risk, avoiding mosquito bites and knowing when to seek medical help are important parts of preparing for your trip.

What Are The Symptoms Of Dengue Fever?

Dengue does not always cause symptoms, but when it does, the illness can begin suddenly and leave you feeling extremely unwell. Symptoms usually develop between four and ten days after a bite from an infected mosquito and can include:

• A high temperature.
• A severe headache, sometimes with pain behind the eyes.
• Muscle and joint pain, which can be intense.
• Nausea or vomiting.
• Swollen glands.
• A skin rash.
• Tiredness and fatigue.

These symptoms can resemble flu and other infections, including malaria, so it is not possible to know for certain what is causing them based on how you feel alone. If you become unwell during or after travelling, seek medical advice and tell the healthcare professional where you have been. If you have visited a malaria-risk area, seek advice urgently so that malaria can be assessed too.

What Is Severe Dengue?

Most people with dengue recover, but a small number develop a more serious form of the illness known as severe dengue. This can cause complications including bleeding, fluid leaking from blood vessels and damage to organs. Without prompt hospital treatment, it can be life-threatening.

Severe dengue is rare in travellers, but it is important to recognise the warning signs. These can appear a few days after the illness begins, sometimes as the fever is starting to come down. A falling temperature can feel like a welcome sign that you are getting better, but if other symptoms appear or worsen at this stage, you need urgent medical attention.

Warning signs can include:

• Severe abdominal pain.
• Persistent vomiting.
• Rapid breathing.
• Bleeding from the gums or nose, or blood in your vomit or poo.
• Extreme tiredness or restlessness.

If you develop any of these symptoms after travelling in an area where dengue occurs, go to hospital as soon as possible. If you are back in the UK, call 999 or go to A&E. Tell the medical team where you have travelled and whether you have already been diagnosed with dengue.

Having had dengue before can increase the risk of severe illness if you are infected again, although this does not mean a second infection will necessarily be severe. Whatever your previous history, the important thing is to seek help promptly if you are unwell and not wait for symptoms to become severe before asking for medical advice.

How Is Dengue Fever Prevented?

The most important way to reduce your risk of dengue is to avoid being bitten by mosquitoes. The Aedes mosquitoes that spread dengue mainly bite during the day, so it is important to protect yourself while you are out exploring as well as when you are relaxing or sleeping.

Use an effective insect repellent on exposed skin, wear clothing that covers your arms and legs where practical, and consider how to keep mosquitoes out of your accommodation. Screens, closed doors and windows, and mosquito nets where needed can all help reduce the chances of being bitten.

Is There A Vaccine For Dengue?

A dengue vaccine is available in the UK and may be considered for some travellers following an individual risk assessment. It is usually considered for people who have previously had dengue and are travelling to an area where there is a risk of infection.

Vaccination may also be considered in some circumstances for someone who has not previously had dengue. This requires a discussion with a travel health clinician experienced in assessing the potential risks and benefits of the vaccine. Your destination, travel plans, medical history and whether the vaccine is suitable for you will all form part of that decision.

The vaccine is not recommended for every traveller and does not replace mosquito bite prevention. Whether or not you are vaccinated, taking precautions against bites remains an important part of protecting yourself from dengue and other mosquito-borne diseases.

Antimalarial medication does not prevent dengue, so you will still need to protect yourself from mosquito bites even if you are taking tablets to prevent malaria.

How Is Dengue Fever Treated?

There is no specific medicine that cures dengue. Treatment focuses on managing symptoms, maintaining hydration and monitoring for signs that the illness is becoming more serious. Most people recover without hospital treatment, but it is important to seek medical advice if you think you may have dengue.

If a healthcare professional advises that you can recover at home or in your accommodation, rest and drink plenty of fluids. Paracetamol can help with fever and pain, provided it is suitable for you and you follow the instructions on the packet or the advice of your healthcare professional.

Avoid aspirin and anti-inflammatory painkillers such as ibuprofen if you have or suspect dengue, as they can increase the risk of bleeding. If you take aspirin or another medicine regularly because it has been prescribed for you, seek medical advice about what to do rather than stopping it yourself.

Some people need to be monitored or treated in hospital, particularly if they have warning signs of severe dengue or are unable to drink enough fluids. Hospital care may include careful monitoring, fluids and treatment for complications.

If you feel worse or develop any warning signs, seek further medical help immediately, even if you have already been assessed. With appropriate care, most people recover, although it is not unusual to feel tired for some time afterwards.

How To Avoid Mosquito Bites When Travelling

Avoiding mosquito bites is one of the most useful things you can do to protect your health while travelling. It helps reduce your risk of malaria and dengue, as well as other infections spread by mosquitoes. It also saves you from at least some of those maddeningly itchy bites.

Different mosquitoes bite at different times, so make bite prevention part of your routine throughout the day and night. No single precaution will prevent every bite, but combining a few practical measures can make a real difference.

Use An Effective Insect Repellent

Apply an effective insect repellent to exposed skin, following the product instructions. A repellent containing 50% DEET is recommended for travel to areas where mosquito-borne diseases are a risk.

If DEET is unsuitable or unavailable, there are effective alternatives. These include repellents containing icaridin, also known as picaridin. For protection against malaria-carrying mosquitoes, a preparation containing at least 20% icaridin is advised. A travel health professional can help you choose a suitable product, particularly if you are travelling with young children or have concerns about your skin or health.

Apply repellent to exposed areas that are easy to miss, such as your ankles, feet and the backs of your hands. Follow the instructions for reapplication, and reapply as needed if mosquitoes begin to take an interest. If you are also using sunscreen, apply it first and the repellent afterwards. Official guidance says to use an SPF 30–50 sunscreen, as DEET can reduce the protection provided by it. Personally I would recommend just going for the 50.

Keep your repellent somewhere accessible during travel, rather than buried at the bottom of your backpack. Mosquitoes don’t wait until you have checked into your accommodation: you may be exposed while waiting for transport, arriving at an airport or making your way to your first night’s stay.

Cover Up Where Practical

Loose-fitting clothing that covers your arms and legs provides an additional barrier against bites. Lightweight, breathable fabrics can make this more comfortable in hot weather. Socks and covered shoes can also help protect your feet and ankles.

You don’t need to spend your entire trip wrapped up from head to toe, but covering more skin can be particularly useful when mosquitoes are active or when you are spending time outdoors. Some mosquitoes can bite through thin or tight-fitting clothing, so loose layers are generally more helpful.

Think About Where You Sleep

Before you settle into a room, have a look at how well it is protected. Screens on windows and doors can help keep mosquitoes out. Air conditioning can also reduce the likelihood of bites, but it is important that the room is kept closed and mosquitoes cannot get in. If a door has been opened, check the room for mosquitoes.

If your accommodation is not adequately protected, or you are sleeping outdoors, use an insecticide-treated mosquito net. Check it for holes and tuck it securely under your mattress or sleeping mat. If you are carrying your own net, make sure you have a way to hang it.

Mosquitoes that spread dengue can bite during the day too, so think about protection if you are resting or sleeping during daylight hours.

Make Bite Prevention Part Of Your Routine

The best precautions are the ones you can use consistently throughout your trip. Keep repellent in your daypack, think about protection when choosing accommodation and adjust your routine when you move to a different environment.

Bite avoidance remains important even if you are taking antimalarial medication or have received a dengue vaccine. Those measures provide protection against particular diseases; reducing mosquito bites can help protect you from several infections at once.

What To Do If You Become Ill During Or After Travel

Feeling ill away from home is never much fun, especially if you are in an unfamiliar place and aren’t sure where to get help. Most illnesses travellers experience will not be malaria or dengue, but if you have been somewhere either disease occurs, it is important to take symptoms seriously and get the right medical advice.

Seek Medical Help While You Are Travelling

If you develop a fever, flu-like symptoms or feel unusually unwell in an area where malaria or dengue occurs, seek medical advice promptly. If you have visited a malaria-risk area, you need urgent assessment. Don’t wait until you get home, continue with a long journey or assume it is just a minor illness that will pass.

Depending on where you are, you may be able to ask your accommodation or travel insurer’s assistance service for help finding a suitable medical facility. If you are somewhere remote, use the plan you made before travelling to reach medical care. Don’t delay seeking urgent treatment while waiting for an insurer to respond.

If you are seriously unwell or develop warning signs such as severe abdominal pain, persistent vomiting, bleeding or rapid breathing, go to hospital as soon as possible or call the local emergency number.

Give A Clear Travel History

When you speak to a healthcare professional, explain that you have been travelling and tell them where you have been. Include the countries and regions you have visited, when you were there and any malaria-risk areas you passed through, even if you stayed only briefly.

Tell them about any antimalarial medication you have taken, any previous dengue infection, your symptoms and when they began. If you have already been assessed, tested or given treatment elsewhere, share those details too. This information helps the healthcare team decide which infections need to be considered and what tests or treatment you may need.

Remember that taking antimalarials does not completely rule out malaria, and you may not remember being bitten by a mosquito. If malaria is a possibility, it needs to be assessed promptly with a blood test.

If you are given a diagnosis or treatment, ask for a written record or keep a copy of any test results and discharge information. This can help if you need further care later in your trip or after returning home.

If You Become Ill After Returning Home

Some infections can develop after your trip has ended, so always mention your travel history when seeking medical advice. This matters even if you felt well while you were away or returned home months ago.

If you develop a fever or other symptoms after visiting a malaria-risk area, seek urgent medical advice from your GP or NHS 111 and explain where you have travelled. Malaria can develop months after infection and, rarely, even later.

If you develop symptoms of severe dengue after visiting a dengue-risk area, call 999 or go to A&E. Do not drive yourself. Tell the medical team about your travel history and any diagnosis or treatment you have already received.

Seek Help Again If You Are Getting Worse

If you have been tested for malaria and the first result is negative, but you are still unwell or malaria remains a concern, seek further medical advice. A single negative test does not always rule malaria out, and a healthcare professional may need to arrange further tests.

If you have been diagnosed with dengue, pay particular attention to the warning signs as your fever starts to settle. Severe abdominal pain, persistent vomiting, bleeding, rapid breathing, extreme tiredness or restlessness need urgent hospital assessment, even if you have already seen a healthcare professional.

Getting checked when something doesn’t feel right is not overreacting. It gives you the best chance of getting the care you need and getting back to your travels when you are well enough.

Be Prepared, Not Scared

Malaria and dengue are worth taking seriously, but they are not a reason to be frightened of travelling. For most backpackers, preparing for mosquito-borne diseases is simply another part of getting ready for a trip, alongside arranging insurance, checking vaccinations and packing a first aid kit.

Take the time to understand the risks along your route, get individual advice before you leave and make mosquito bite prevention part of your everyday routine. If you need antimalarial medication, take it as advised, and if you become ill during or after your trip, don’t hesitate to seek medical help.

You can’t prevent every bite or remove every risk, and you don’t need to spend your gap year worrying about mosquitoes. A little preparation means you can look after your health while getting on with what you came to do: exploring, having adventures and enjoying your travels.