troublesome tropical travellers
TRANSCRIPT
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/