This talk on "Fevers in Travellers" focusses history taking skills, diagnosis and treatment of Malaria and some other tropical disease that we may on rare occasions encounter in the urban ED environment of New South Wales. I would like to thank Dr Julian Chow, and his sources, for sharing this comprehensive talk on the topic, which was presented as part of the Wollongong Emergency Medicine registrar teaching program. We would welcome comments and further contributions on this topic.
1. Dr Julian Chow
Registrar Teaching at M&M Meeting
Wollongong Hospital Emergency Department
25th June 2014
2. Case study
Malaria overview
Fever in travellers from an Emergency
Department perspective
3. 36 y/o gentleman
PC:- Fevers with recent travel
Background:-
◦ Recently returned from Benin and Togo
◦ Generally fit and well, nil regular medications
4. Returned from travels 2 weeks ago
◦ 1/52 h/o intermittent fevers, nocturnal diaphoresis, myalgias, arthralgias,
bilateral frontal headache, nausea, anorexia and weight loss of 2 kg
◦ Symptoms worsened over the last 2/7
Referred by GP to I.D. via Emergency Department
◦ Positive thick and thin blood films and antigen test for P. Falciparum
◦ HIV negative
◦ Syphilis negative
Social history
◦ 2010 – Migrated from Togo to Australia
◦ 3 months travelling in Benin and Togo, West Africa to see family
◦ No h/o unwell whilst there. No precautions or chemoprophylaxis taken
◦ Mainly stayed with family in metropolitan area, no new sexual contacts /
tattoos / blood transfusion / hospitalisation
◦ Currently unemployed, single and lives with local Australian housemates
5. BP 124/76, 97 bpm, RR 20, 96% RA, 37.0C
Looks well, not in discomfort
◦ Examination fairly unremarkable
◦ Spleen edge
◦ No rashes or visible bites
6. ECG sinus rhythm
Urine analysis – NAD
Hb 151, WCC 5, Plat 98, MCV 72.7, MCH 26
UEC Ur 7.4, rest NAD
GGT 124, ALT 50
CXR - NAD
7. Admitted Dr. Adams, Infectious Diseases
◦ Artemether 80 mg + Lumefantrine 480 mg PO BD
◦ Artemisinin-based Combination Therapy (ACT)
◦ Continue for next 3/7
Repeated bloods 1/7 after admission – similar
◦ Discharged home
◦ Follow up 1/52 with ID
Bloods 1/52 after
◦ Thrombocytopenia resolved to 268
◦ LFT still remained deranged
9. Affects up to 3 billion people worldwide
Half the world’s population at risk
10. Malaria caused by Plasmodium Parasites
◦ Plasmodium falciparum (most common & lethal)
◦ Plasmodium vivax
◦ Plasmodium malariae
◦ Plasmodium ovale
Transmitted vector exclusively Anopheles
◦ Feeds at night, after monsoons
◦ Exclusively female mosquitoes
◦ Usually human hosts
11.
12. Should be suspected if history of fever
Recently visited malaria endemic area
regardless of adherence to prophylaxis
Incubation period
◦ Minimum is 6 days
◦ Falciparum in first month, all within <6 months
◦ Vivax or Ovale present later 6 months to few years
13. Physical examination – often unremarkable
Recurrent cyclical fever and sweating
◦ Every 36 hours / tertian fever / quartan fever
Children more likely with signs
◦ Hepatomegaly, splenomegaly, somnolence
Severely ill patients
◦ Jaundice, confusion, seizures
15. Blood smear + microscopy (EDTA tube)
◦ Thick slides – evaluation of parasitic count
(>2% RBC is severe)
◦ Thin slides – evaluation of type of malaria
Rapid diagnostic test (RDT)
◦ Capillary blood onto test strip, qualitative test only
17. Safety of outpatient treatment
Children with Falciparum should be admitted
for 24 hours
Consider admission for pregnant women,
infants and elderly as deteriorate rapidly
All patients to be discussed with specialist
18. Dependent on origins and parasite subtype
Uncomplicated P. Falciparum (PO)
◦ Artemisinin-based Combination Therapy (ACT)
Artemether + Lumefantrine
◦ Atovaquone + Proguanil
◦ Quinine Sulphate + Doxycycline / Clindamycin
Severe malaria (IV)
◦ Artesunate or Quinine Dihydrochloride
Other malaria
◦ ACT or Mefloquine
19. Vector avoidance
Chemoprophylaxis
◦ Not always effective, advise if symptoms develop to
see medical professional
◦ Dependent on areas visiting
Chloroquine susceptible/resistant areas
Mefloquine resistant areas
21. QUESTIONS EXAMPLES
Country of origin and
country of travel
Latent disease, possible exposures
Occupation, hobbies,
activities
Farmer, abattoir worker, cave explorer, swimming
Prophylaxis Immunisations, malaria prophylaxis, insect repellents
Treatments or procedures Blood transfusions, injections, splenectomy, gastrectomy,
tattoos
Drugs Prescribed, over-the-counter, illicit
Diet Seafood, raw food, traditional or homemade food
Sex Unprotected sex, HIV partner, multiple partners, commercial
sex
Allergies Antibiotics, food, insect bites, plant
Pets Birds, dogs, cats, other
Family history Diabetes, sickle-cell anaemia, tuberculosis
Bites Insects, snake, animal, spider, human
22.
23. * Evaluation should also include the differential diagnoses that would be considered in
a non-traveller with fever
† Travel to high-risk area, rural or prolonged travel, non-compliance with prophylaxis
24.
25. Full septic screen, LFT + thick & thin slides
Reverse barrier nursing + isolated room
Negative pressure rooms if aerosol infection (SARS)
Ensure staff are vaccinated and minimise number of
staff in contact with patient
Public health department to be contacted
SEEK EXPERT ADVISE
26. Haemorrhage (or bruising)
Neurologic impairment (mental status or
paralysis)
Acute respiratory distress
Skin changes (rashes or jaundice)
27. Both Aedes mosquito borne viral infection
◦ Similar Sx - Fever, malaise, N&V, headache, myalgia
◦ Southern Asia, western Pacific, central Africa, South America
◦ Virology or antibodies in serum
Dengue
◦ Incubation period 4-7 days
◦ Bone pain (“break bone fever”)
◦ Transient macular rash, petechia, lymphadenopathy,
hepatomegaly
◦ Reduced WCC and platelets, deranged LFT
◦ Recover after 3-7 days with symptomatic Rx
◦ Dengue shock syndrome (DSS) – ↓plasma protein, hypotension,
pleural effusions, ascites, bleeding. Mx supportive and fluid +/-
Chikungunya
◦ Rarely fatal. Joint pain may persist for several months
◦ Mainstay of Rx is symptomatic management
28. Salmonella typhi and S. Paratyphi
◦ Faeco-oral transmission route
◦ Incubation period 7-14 days
Malaise, fever, dry cough, abdo discomfort,
constipation/diarrhoea, splenomegaly, confusion
or hallucinations
Rose spots – pink macular spot
Ix – mild anaemia, WCC normal
Mx – Isolate, barrier nursing, ID admission,
Ciprofloxacin or Cefotaxime
29. Key in history
Isolation + sepsis pathway
Tropical medicine is a vast specialty
Seek specialist advise from Infectious
Diseases in all travellers with fevers
Normal haemoglobin levels, mild microcytosis and hypochromic
Mild thrombocytosis
Slightly dry with a urea of 7.4
Mildly deranged LFT
Predominantly those living in Sub Saharan Africa where healthcare is poorly accessible.
Widely pandemic in the Americas, South and South East Asian countries and to some extent part of Europe.
207 million cases of malaria in 2012, 42% mortality rates in Africa
In Africa where a child dies every minute from malaria
Three main stages, human liver stage, human blood stage and the mosquito stage
During a blood meal, mosquito inoculates sporozoites into human host
These then infect hepatocytes
Which mature to schizonts
The rupture of schizonts into blood stream
Infects red blood cells
May either mature to form more Schizonts which further ruptures to spread the infection
Or mature to male or female Gametocytes
Anopheles mosquito strikes back, ingests the Gametocytes which multiplies within the mosquito’s stomach
Eventually, spreads to the salivary glands of the mosquito
In pandemic areas, undiagnosed fever is malaria until proven otherwise. Can lead to resistance
To rule out malaria, at least 3 slides need to be negative. Must be taken 12-24 hours apart