Makindo Medical Notes

Related Subjects: |Fever in a traveller |Malaria Falciparum |Malaria Non Falciparum |Viral Haemorrhagic Fevers (VHF) |Lassa fever |Dengue |Marburg virus disease |AIDS HIV |Yellow fever |Ebola Virus |Leptospirosis |Crimean-Congo haemorrhagic fever |African Trypanosomiasis (Sleeping sickness) |American Trypanosomiasis (Chagas Disease) |Incubation Periods |Notifiable Diseases UK

🌡️ Fever = ≥38°C. Any patient returning from a malarial area in the past 3 months with flu-like symptoms must be assumed to have falciparum malaria until proven otherwise. 🦟 Always send urgent thick & thin films. Hours matter. Mortality can occur before the post-take ward round. 👉 Non-falciparum malaria may present up to 1 year later, but falciparum rarely after 3 months.

⚠️ Red Flags & Key Rule-Out

• 🦟 Malaria = most important diagnosis to exclude → thick & thin blood films, repeat if negative.
• 🧍‍♂️ Ask: Does this patient need isolation? (e.g. Ebola, MERS, VHF).
• 💊 Think antimicrobial resistance if hospitalised in Africa/Asia/Middle East.

🌍 Common Causes of Fever in Travellers

⏳ Incubation Period Clues

🧪 Investigations

• 📊 FBC, Differential WCC, U&E, LFTs, Glucose, CRP
• 🦟 Malaria: rapid antigen test + thick/thin films (repeat 12–24 hrs if negative)
• 💉 Blood cultures (aerobic & anaerobic)
• 🧫 Urine MCS, Stool culture (esp. Salmonella/typhoid)
• 🫁 CXR (pneumonia/TB), Abdominal USS (abscess, hepatosplenomegaly)
• 🧬 HIV, viral serologies as indicated
• ♀️ Pregnancy test (guides imaging/drug safety)

💡 Teaching Pearls

• 🦟 Malaria = until proven otherwise. Never send home a febrile traveller without excluding it.
• ⏱️ Repeating films is vital → parasites may not be detectable initially.
• 🌍 Always ask: where, when, how long, exposures (mosquitoes, fresh water, animals, food)?
• 👩‍⚕️ If uncertain, isolate first, then investigate → protect staff & public health.
• 📚 Non-falciparum malaria (vivax/ovale) may relapse months later due to dormant liver hypnozoites.

Cases — Fever in a Traveller

• Case 1 — Malaria (Falciparum): A 30-year-old man returns from Nigeria with fever, sweats, and headache. He took no prophylaxis. Exam: febrile, mild jaundice, splenomegaly. Blood film: trophozoites of *Plasmodium falciparum*. Diagnosis: Malaria. Management: Admit; treat with IV artesunate if severe, or oral artemisinin-based combination therapy if uncomplicated.
• Case 2 — Typhoid Fever: A 25-year-old woman returns from India with 7 days of fever, abdominal pain, and constipation. Exam: relative bradycardia, “rose spots” on abdomen, tender hepatosplenomegaly. Blood culture: *Salmonella typhi*. Diagnosis: Enteric fever. Management: IV ceftriaxone (or azithromycin if sensitive); supportive fluids and monitor for intestinal perforation.
• Case 3 — Dengue Fever: A 22-year-old student returns from Thailand with fever, severe myalgia (“breakbone fever”), retro-orbital pain, and a blanching rash. Platelets 95 ×10⁹/L, haematocrit rising. Diagnosis: Dengue fever. Management: Supportive care, fluids, avoid NSAIDs/aspirin; admit if warning signs (abdominal pain, bleeding, rising haematocrit).
• Case 4 — Rickettsial Infection (African Tick Bite Fever): A 35-year-old safari traveller in South Africa presents with fever, headache, and an eschar at the site of a tick bite. Exam: generalised rash and lymphadenopathy. Diagnosis: Rickettsial infection. Management: Doxycycline, supportive care. Usually rapid response.
• Case 5 — Acute Schistosomiasis (Katayama Fever): A 28-year-old backpacker returns from Uganda after swimming in Lake Victoria. He has fever, eosinophilia, cough, and urticaria. Diagnosis: Acute schistosomiasis (Katayama fever). Management: Symptomatic initially; definitive therapy with praziquantel once infection established.

Teaching Commentary 🌍

Fever in a returning traveller is always malaria until proven otherwise. Key initial steps: detailed travel history (location, exposures, prophylaxis, vaccines), prompt malaria film/RDT, and infection control if viral haemorrhagic fever possible. Important differentials: malaria, enteric fever, dengue, rickettsial infections, viral hepatitis, schistosomiasis, HIV seroconversion. Red flags: altered mental state, hypotension, jaundice, bleeding, severe thrombocytopenia. Early recognition and empiric management (while awaiting confirmation) saves lives.