Troublesome Tropical Travellers

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Troublesome Tropical Travellers

Dr Patrick Lillie

Consultant, Acute Medicine and

Infectious Diseases, SGH

Outline

• Why worry about returned travellers?

• Investigations / assessment

• Undifferentiated febrile illness

– Malaria

– Viral Haemorrhagic Fevers

– Arboviral infections (Dengue, Zika, Chikungunya)

– Enteric Fever

– Leptospirosis

• Odds and ends

Tropical medicine

• Increased travel to the tropics – visiting

relatives, backpacking, business

• Malaria is the big thing to know about, but

remember standard infections

• Fever, diarrhoea and rashes are the

commonest things people present with

Acute and potentially life threatening tropical

infections – Geosentinel survey 1996-2011

82, 825 ill Western travellers (57 sites in 26 countries)Jensenius et al. Am J Trop Med

Hyg 2013

Jensenius et al. Am J Trop Med Hyg 2013

Presentation of infections after travel

Wilson et al. CID (2007) Geosentinel survey

Leder et al. Ann Intern Med 2013 Geosentinel surveillance of Returned Travellers 2007 - 2011

Approximately 23.3% of ill returning travellers present with a fever

What to ask

• Where they’ve been (rural / urban), hotels,

hostels, stop offs

• When did they go, how long for, how long

back

• What did they do (safari, animals, water

exposures). Vaccines and prophylaxis

• Presenting features (fevers, rash, diarrhoea)

1112

1283

1401 1388

1504

1576 1576

1469

1339

1221

13381386

11391087

1179

1263

1149

1002

1192 1174

4 11 13 7 14 16 9 9 16 5 11 8 5 6 6 7 8 2 7 3

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Year

Malaria Cases UK, 1995-2014

P.falciparum Deaths

Broderick et al, BMJ open 2012

Risk factors for malaria mortality

Checkley et al, BMJ 2012

Risk factorNo (%) of

fatal cases

Odds ratio (95% CI) of death

Crude P value Adjusted* P value

Purpose of visit to country

with endemic malaria:

Tourism81/2740

(2.96) 9.4 (6.1 to

14.7)<0.001

8.2 (5.1 to

13.3)<0.001

Visiting friends and

relatives

26/8077

(0.32)

Calendar month of

presentation:

December49/1922

(2.55) 4.5 (3.2 to

6.2)<0.001

3.7 (2.6 to

5.2)<0.001

All other months135/23 132

(0.58)

Birth in African country with

endemic malaria:

No142/5849

(2.43) 6.2 (4.3 to

8.9)<0.001

4.6 (3.1 to

9.9)<0.001

Yes36/8937

(0.40)

Checkley et al, BMJ 2012

Risk factors for malaria death in the UK

Checkley et al, BMJ 2012

Symptoms / Signs

• Very non specific

• Fever, muscle aches, diarrhoea, headache,

coma, respiratory distress

• Lab findings – thrombocytopenia, anaemia,

raised LDH, renal impairment, DIC

Pathophysiology of severe malaria

• Anaemia – red cell destruction and

sequestration, marrow suppression

• Micro-vascular obstruction, cytokine

dysfunction

• Hypoglycaemia of unknown cause

• Capillary leak / increased vascular permiability

Severe malaria

Artemisin drugs

• The best treatment for malaria (SEAQUAMAT and AQUAMAT)

• Active against drug resistant strains of P. falciparum, but new evidence of resistance in SE Asia

• Lower parasitaemia much quicker than other drugs

• Used in combination normally – resistance emerges if used alone

Artesuntate for malaria

SEAQUAMAT AQUAMAT

Lancet, 2010Lancet, 2005

Drug management

• 1st line – IV artesunate 2.4mg/kg at 0, 12 and

24 hours then daily.

• If no artesunate available – IV quinine

20mg/kg (up to 1.4g) loading dose then

10mg/kg (700mg) t.d.s. + 2nd agent

(doxycycline / clindamycin if pregnant)

• Exchange transfusion – consider if

parasitaemia >20%, use artesunate first

Non Severe falciparum

• All patients with falciparum should be

admitted initially.

• Riamet (Co-artemether) is the preferred

treatment, Malarone or Quinine + doxycyline

as alternatives

• Will need daily FBC and blood films

Non falciparum malarias

• Almost always managed as an outpatient

• Chloroquine remains the drug of choice, given

orally

• For vivax and ovale, to erradicate hypnozoites

primaquine for 2 weeks needed

• Need G6PD levels before using primaquine

Ebola / VHF issues

VHF assessment

Viral Haemorrhagic Fevers

• Very rare, but everyone worries about them!

• Risk assessment for VHF should be done on all

patients returning from an endemic area with

a febrile illness

• 23.3% of patients tested during the Ebola

outbreak had malaria (1% had Ebola)

It’s Friday, it’s 5 to 5pm…

• 28 year old woman, returned 5 days ago from

north eastern Zimbabwe / Zambian border.

• Stayed on a farm, daughter bitten by a tick

• Had an unexplained bite on her arm

• Treated for malaria 1 week ago whilst there

• Fever, diarrhoea, subtle rash, myalgia

Risky exposure

• “Oh and a bat urinated on my head”

• Negative malaria film, therefore VHF risk

• PCR tests – CCHF, Ebola, Marburg, Rift Valley

Fever, Leptospira, Ricketsia, Lassa, Malaria

• All negative – stool culture positive for Shigella

sonneii

Southampton possible VHF casesGender Age Country visited Risk group Final diagnosis

Female 32 Seirra Leone HCW, Ebola

outbreak

Unknown

Male 42 Seirra Leone Ebola outbreak Unknown

Female 34 Seirra Leone HCW, Ebola

outbreak

Malaria

Male 28 South Sudan Animals, health

care

Unknown

Male 43 Liberia Ebola outbreak Cholecystitis

Female 30 Uganda HCW Possible tick

typhus

Female 30 Zimbabwe Bat Urine, ticks Shigellosis

Tropical fever and rash

• Short history, joint pains and diffuse macular

rash

– Arboviruses (Dengue, Zika, Chikungunya)

– Typhus

– Measles, Rubella

– Parvovirus

– Rheumatic fever

ArbovirusesWide global distribution

Dengue

• ≤10 day incubation

period

• Abrupt onset fever,

arthralgia and rash

• Retro-orbital pain

classically

• Marked

thrombocytopaenia,

transaminitis and

leucopaenia

Zika

• Clinically

indistinguishable from

dengue (often milder,

80% subclinical). Rash

sometimes itchy

• First described in

Uganda

• Microcephaly and post

infective neurological

complications a concern

Testing for Zika

Men

• If symptomatic

– Serum, EDTA and urine if

partner pregnant

• Previously symptomatic and

partner pregnant

– Semen

• Asymptomatic

– No testing

Women

• Symptomatic, not pregnant

– Serum and EDTA

• Symptomatic, pregnant

– Serum, EDTA and urine

• Previous symptoms,

pregnant

– No viral tests, USS and

obstetric follow up

Rickettsial disease

• Tick / louse / mite

borne disease

• High fevers, myalgia,

vasculitic looking rash

• Look for eschar of tick

bite

• Responds quickly to

doxycycline

García-García, AJTMH 2010

HIV Seroconversion rash

• Tend not to get rashes

with EBV glandular

fever (unless amoxicillin

induced)

• Widespread macular

erythematous

• Consider streptococcal,

parvovirus and syphillis

• Can involve hands and

feet

Enteric fevers

• Salmonella typhi / paratyphi A-C

• Undifferentiated febrile illness, GI disturbance

• Incubation period 3 – 60 days (generally 14-

21). Faeco-oral transmission

• Vaccine is partially protective against S.typhi

not paratyphi

• Most common in Indian subcontinent / SE

Asia, increasing drug resistance

Enteric fevers• Multiple complications

– most serious are

perforation, coma,

shock

• Typhoid facies

• Rose spots

• Treatment – Ceftriaxone

or azithromycin initially

(quinolones are best,

but very high resistance

rates).

Leptospirosis

• Zoonotic infection with

Leptospira interrogans /

ictahaemorrhagica

• Found in urine of

rodents, cattle, multiple

other animals

• Often acquired during

water exposure (tubing

down the Mekong)

Leptospirosis

• Undifferentiated febrile illness

• Marked myalgia, conjunctival suffusion

• Hepatic / renal dysfunction (disproportionate

bilirubin)

• Meningo-encephalitis and pulmonary

haemorrhage are uncommon but bad news

• Sensitive to various antibiotics, commonly

doxycycline or ceftriaxone used

Tropical skin lesions• Leishmaniasis

– Cutaneous / mucocuatneous

– Rolled edge, multiple or single

– Transmitted by sandflybites

– Old world less worrying, new world worse

– Pentavalentantimonials for treatment

Tropical skin again

• Cutaneous larva migrans

– Migration of the dog /

cat hookworm

through skin

– Often after walking on

beaches with faeces

on

– Serpiginous rash, itchy

– Mebendazole /

albendazole /

ivermectin

Eosinophillia post tropical travel

• Worms

– Schistosomiasis (African Great Lakes)

– Strongyloidiasis (All tropical areas)

– Filarial infection (Lymphatic filariasis,

onchocerciasis, loa loa) Asia / West Africa

– Liver / lung flukes (Fascioliasis, Opsithorciasis,

Paragonamiasis) Mostly SE Asia

• Stool microscopy, serology, blood films

Geographically restricted infections

• Fungi

– Histoplasmosis (Mississipi delta, caves / rural elsewhere in Africa / S.America / Asia)

– Penicilliosis – SE Asia only

– Coccidiodies – Arizona / southern USA

– Paracoccidiodes – S.America

• Melioidosis – SE Asia, paddy fields / soil

All the above present as fevers, cough, skin lesions, TB like disease

Helpful things

• Local ID team

• WHO website for outbreak information -

http://www.who.int/csr/don/en/

• Public Health England website -

https://www.gov.uk/government/organisation

s/public-health-england

• British Infection Association guidelines -

http://www.britishinfection.org/guidelines-

resources/published-guidelines/

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