Post-Travel Illness: What Returning Travellers Need to Know and When to Seek Help

Reviewed by GPhC Pharmacist at Halton Pharmacy, Leeds

Most travel health advice focuses on getting ready to go vaccines, malaria tablets, avoiding bites. But coming home matters just as much, and it’s talked about far less.

Some infections picked up abroad don’t show symptoms until days, weeks, or even months after you’re back. A few especially malaria can get serious fast without quick diagnosis and treatment.

Key rule: If you have a fever after travelling, treat it as a medical emergency until malaria has been ruled out. This applies even if you took antimalarial tablets.

Fever After Travel: Always Take It Seriously

Malaria (Plasmodium falciparum) is the most dangerous type. Without treatment, it can lead to organ failure or death within 24–48 hours of symptoms starting.

Important facts:

• Antimalarial tablets reduce your risk they don’t remove it completely.
• No antimalarial tablet gives 100% protection.
  
  

The rule: If you develop a fever within 3 months of returning from a malaria-risk country, get seen urgently and have a malaria blood test no matter how carefully you took your tablets.

Other post-travel illness to know about:

• Dengue fever  fever, severe muscle pain, rash, pain behind the eyes. Usually shows up within 2 weeks of return.
• Typhoid fever fever 1–3 weeks after return, often with stomach symptoms.
• Chikungunya fever with severe joint pain.
• Viral haemorrhagic fevers  rare, but possible after travel to sub-Saharan Africa.

Common Post-Travel Illness

Stomach and Gut Issues

• Traveller’s diarrhoea is the most common illness picked up abroad. It usually clears up within 7–14 days.
• If diarrhoea lasts more than 2 weeks, get a stool test. It could be a parasite infection like Giardia, Entamoeba, or Cryptosporidium.
• Treatment depends on which parasite (if any) is found.

Skin Conditions

• Cutaneous larva migrans  an itchy skin infection from hookworm larvae in soil or sand
• Myiasis  infection from botfly larvae
• Infected insect bites
• Tinea versicolor  a common fungal skin condition
  
  

Most of these aren’t dangerous, but they do need proper identification and treatment.

Schistosomiasis: Often Missed

If you’ve had contact with freshwater in:

• Sub-Saharan Africa
• The Nile river system
• Parts of the Middle East
• Southeast Asia
  
  

You should be tested for schistosomiasis when you return ideally 8–12 weeks after exposure.

• A raised white blood cell count (eosinophilia) on a routine blood test can be an early clue.
• Katayama fever (the acute form) can cause fever, cough, hives, and stomach pain in the weeks after exposure and is often misdiagnosed.
  
  

See our dedicated schistosomiasis blog for more detail.

When to See a GP vs. When to Go to A&E

 Go to A&E or call 999 if:

• You have a fever and have been to a malaria-risk country in the last 3 months
• You’re getting worse quickly
• You have a severe rash with fever
• You’re confused or losing consciousness

 See a GP urgently (same day) if:

• You have any fever within 4 weeks of returning from a tropical destination — even if you’re not getting worse
• Diarrhoea has lasted more than 2 weeks
• You’ve developed an unexplained rash after travel
• You notice blood in your urine after freshwater exposure
  
  

Note: Halton Pharmacy can give initial advice and point you to the right care, but we can’t diagnose or treat tropical infections ourselves.

Post-Travel Health Checks

Some travel clinics and GP practices offer a structured check-up for high-risk travellers, which may include:

• Full blood count (checking for eosinophilia)
• Liver function tests
• Hepatitis screening
• HIV and STI screening, where relevant
• Schistosomiasis blood test
• TB testing for long-stay travellers in high-risk areas
  
  

If you had significant exposure risk during your trip, ask your GP or travel health provider about this.

This article is for general information only. It’s not personal medical advice. To talk about travel health at Halton Pharmacy, Selby Road, Leeds LS15 7JR, please book a travel health consultation.