Travel Related Infection Flashcards
what are the unfamiliar features of imported disease?
presenting features isolation requirements diagnostic methods treatment/management unexpected complications
how are travellers at risk of infection?
temptation to take risks away from home
different epidemiology of some diseases
incomplete understanding of health hazards
stress of travel
refugees - deprivation, malnutrition, disease, injury
name some infections that are common worldwide
influenza
community acquired pneumonia
meningococcal disease
STI
name some climate or environment related health problems
sunburn heat exhaustion and heatstroke fungal infections bacterial skin infections cold injury altitude sickness
infections controllable by public health measures: sanitation
- Traveller’s diarrhoea
- Typhoid
- Hepatitis A or E
- Giardiasis
- Amoebiasis
- Helminth infections
- Viral gastroenteritis
- Food poisoning
- Shigella dysentery
- Cholera
- Cryptosporidiosis
infections controllable by public health measures: immunisation
poliomyelitis
diphtheria
infections controllable by public health measures: education
HIV
STIs
name some water related infections
- Schistosomiasis
- Leptospirosis
- Liver flukes
- Strongyloidiasis
- Hookworms
- Guinea worms
name some arthropod-borne infections and their vector
- Malaria (mosquitos)
- Dengue fever (mosquitos)
- Rickettsial infections (ticks: typhus)
- Leishmaniasis (sand flies: Kala-azar)
- Trypanosomiasis (tsetse fly: sleeping sickness)
- Filariasis (mosquitos: elephantiasis)
- Onchocerciasis (black flies: river blindness)
name some emerging infectious diseases and where
- Zika: Latin America, Caribbean
- Ebola virus disease: West Africa
- MERS-CoV: Middle East
- Swine ‘flu (H1N1): worldwide
- Avian ‘flu (H5N1 and H7N9): China
- SARS: Far East, worldwide
- West Nile Virus: USA
what is the malaria vector?
female Anopheles mosquito
name the 5 species of malaria
plasmodium falciparum plasmodium vivax plasmodium ovale plasmodium malariae plasodium knowlesi
clinical features of malaria: symptoms
fever rigors aching bones abdo pan headache dysuria frequency sore throat cough
clinical features of malaria: signs
none
splenomegaly
hepatomegaly
mild jaundice
list complications of malria
cerebral malaria (encephalopathy) blackwater fever pulmonary oedema jaundice severe anaemia algid maria
who is vulnerable to cerebral malaria (encephalopathy)?
non-immune visitors
children in endemic areas
what does cerebral malaria (encephalopathy) cause?
hypoglycaemia
convulsions
hypoxia
what is blackwater fever
severe intravascular haemolysis high parasitaemia profiund anaemia haemoglobinuria acute renal failure
what kind of septicaemia (gram +ve/-ve) does algid malaria produce?
gram -ve
diagnosi of malaria
thick and thin blood films - Giemsa, Field’s stain
Quantitative buff coat
Rapid antigen tests - OptiMal, ParaSight-F
for complicated malaria you need one or more of:
impaired consciousness or seizures hypoglycaemia parasite count >= 2% haemoglobin <= 8mg/dl spontaneous bleeding/DIC haemoglobinuria pH < 7.3 pulmonary oedema or ARDS shock
SE of quinine
nausea tinitus deafness rash hypoglycaemia IV - cardiac depression , cerebral irritation
treatment of uncomplicated p falciparum
riamet 3 days
euratesim 3 days
malarone 3 days
quinine 7 days plus oral doxycycline or clindamycin
treatment of complicated or severe p falciparum
IV artesunate (unlicensed in UK) IV quinine + oral doxy/clindamycin
treatment of p vivax, p ovale, p malariae, p knowlesi
chloroquine 3 days
riamet 3 days
add primaquine 14 days in vivax and ovale to eradicate liver hypnozoites
when giving primaquine which exzyme do you need to check for deficiency in?
G6PD
what organisms cause enteric fever?
salmonella typhi
salmonella paratyphi
clinical features of enteric fever: incubation period
7 days - 4 weeks
clinical features of enteric fever: 1st week
fever headache abdo pain constipation dry cough relative bradycardia neutrophilia confusion
clinical features of enteric fever: 2nd week
fever peaks at 7-10 days rose spots diarrhoea begins tachycardia neutropneia
clinical features of enteric fever: 3rd week (complications)
intestinal bleeding
perforation
peritonism
metastatic infection
diagnosis of enteric fever: clinical
not easy
based on evolution of features
diagnosis of enteric fever: lab
culture blood, urine, stool
culture bone marrow
treatment of enteric fever
oral azithromycin
IV ceftriaxone
clinical features of dengue fever
sudden fever severe headaches, retro-orbital pain severe myalgia and arthralgia macular/maculopapular rash haemorrhagic signs - petechiae, purpura, positive tourniquet test
diagnosis of dengue fever: clinical
thrombocytopenia
leukopenia
elevated transaminases
positive tourniquet test
diagnosis of dengue fever: lab
PCR
Serology
management of dengue fever
no specific
IV fluids
fresh frozen plasma
platelets
complication sof dengue fever
dengue haemorrhagic fever
dengue shock syndrome
prevention of dengue fever
avoid bites
new vaccine - dengvaxis
where is schistosomiasis found?
freshwater
freshwater snails
what organisms can cause schistosomiasis ?
schistosoma haematobium
s. mansoni
s. japonicum
clinical features of schistosomiasis: 1st few hours
swimmers itch clears after 24-48 hrs
clinical features of schistosomiasis: invasive stage > 24 hrs
cough
abdo discomfort
splenomegly
eosinophilia
clinical features of schistosomiasis: karaymama fever (15-20 days)
prostrate fever urticaria lymphadenopathy splenomegaly diarrhoea eosinophilia
clinical features of schistosomiasis: acute disease (6-8 weeks)
eggs deposited in bowel (dysentery) or bladder (haematuria)
diagnosis of schistosomiasis
clinical diagnosis
antibody tests
ova in stools and urine
rectal snip
treatment of schistosomiasis
praziquantel 20mg/kg, two doses 6 hrs apart
prednisolone if severe
organisms and diseases of rickettsiosis
tick typhus - r. conorrii, r. africae rocky mountain spotted fever - r. rickettsi endemic typhus - r. prowazeki murine or endemic typhus - r. mooseri scrub typhus - r, tsutsugamushi
what type of rickettsiosis is most common imported to the UK?
tick typhus
where does tick typhus come from?
Southern Africa
Mediterranean
Arabian Gult
signs and symptoms of tick typhus
abrupt onset swinging fever headache confusion endovasculitis rash (macular, petechial) bleeding
diagnosis of tick typhus
clinical features
serology
treatment of tick typhus
tetracycline
give examples of viral haemorrhagic fevers
ebola
congo-crimea haemorrhagic fever
lassa fever
marburg disease
what is the maximum incubation period for viral haemorrhagic fevers?
3 weeks
what is the treatment for viral haemorrhagic fevers?
supportive
what type of virus is zika?
flavivurus
how is zika transmitted?
daytime biting Aedes mosquito
sexual contact
blood transfusion
what is Zika related to?
dengue
yellow fever
Jap B encephalitis
West Nile virus
clinical features of zika
mild or no symptoms headache rash fever malaise conjunctivitis joint pains Guillain-Barre syndrome
in pregnancy what can zika cause?
microcephaly and other neurological problems
returned traveller. what diseases cause rash?
typhoid
thypus
dengue
returned traveller. what diseases cause jaundice?
hepatitis
malaria
yellow fever
returned traveller. what diseases cause lymph nodes?
leishmania
trypanosomiasis
returned traveller. what diseases cause hepatomegaly?
malaria
typhoid
amoebic abscess
returned traveller. what diseases cause spleenomegaly?
visceral leishmaniasis
typhoid
malaria
