Travel related infections Flashcards
Why are travellers vulnerable to infection? (5)
temptation to take risks away from home
different epidemiology
incomplete understanding of health hazards
stress of travel
refugees: deprivation, malnutrition, disease, injury
List some infections common worldwide
influenza
STD
community acquired pneumonia
meningococcal
List some climate or environment related health problems
sunburn heat exhaustion and heat stroke cold injury altitude sickness fungal infections bacterial skin infections (staph aureus)
Infections controllable with sanitation
travellers diarrhoea hepatitis A/E typhoid cholera food poisoning shigella dysentery helminth infection
Infections controllable with immunisation
poliomyelitis
diptheria etc
Infections controllable with education
HIV and AIDS
6 water related infections
schistosomiasis leptospirosis liver flukes stronglyloidiasis hook worms guinea worms
List some arthropod borne infections
malaria
dengue fever
rickettsial infections
leishmaniasis
list some emerging infectious diseases
zika
ebola
swine and avian flu
Vector for malaria
female anopheles mosquito
5 species of malaria
severe = plasmodium falciparum
P. vivax, ovale, malariae, knowlesi
symptoms of malaria
fever, rigors, aching bones, abdominal pain, headache, dysuria and frequency, sore throat and cough
Possible signs of malaria
splenomegaly
hepatomegaly
mild jaundice
6 complications of malaria
cerebral malaria blackwater fever jaundice pulmonary oedema severe anaemia algid malaria = gram -ve septicaemia
Black water fever
severe complication of malaria causing haemoglobinuria, acute renal failure, high parasitaemia, profound anaemia and severe intravascular haemolysis
3 ways to diagnose malaria
thick and thin blood films - giemsa, fields stain
quantitative buffy coat - centrifugation, UV microscopy
Rapid antigen tests
Try and name the 9 things which makes malaria complicated
haemoglobinuria haemoglobin <8mg/dl parasite count >2% pulmonary oedema or ARDS renal impairment or pH<7.3 hypoglycaemia cerebral malaria spontaneous bleeding shock - algid malaria
4 treatments and durations for uncomplicated P. falciparum
riamet - 3 days
eurartesim - 3 days
malarone - 3 days
quinine - 7 days (+oral doxycycline)
Side effects of quinine
nausea, deafness, tinnitus, rash, hypoglycaemia
2 treatments of complicated P.falciparum
IV artesunate
IV quinine + oral doxycycline
Side effects of IV quinine
cardiac depression, nausea and vomiting
3 treatments of P.vivax, ovale, malariae, knowlesi and duration
chloroquine - 3 days
riamet - 3 days
primaquone
When is primaquone used in treatment?
P. vivax and ovale
or to eradicate liver hypnozoites
What must you check for before giving primaquine?
G6PD deficiency
4 malaria control programmes
mosquito breeding sites - drain standing water
larvacides
mosquito killing sprays
human behaviour
2 causative organisms of typhoid fever
salmonella typhi
salmonella paratyphi
How is salmonella (para) tyhphi spread?
poor sanitation and unclean drinking water
incubation period of typhoid fever
7 days to 4 weeks
1st week typhoid fever symptoms
fever, headache, abdo discomfort, constipation, dry cough, relative bradycardia, neutrophilia, confusion
2nd week typhoid fever symptoms
fever peaks at 7-10days, rose spots on trunk, diarrhoea, tachycardia, neutropenia
3rd week complications of typhoid fever
perforation, intestinal bleeding, peritonism, metastatic infection
relapse % in 4th week of typhoid fever
10-15
Why is clinical diagnosis of typhoid fever difficult?
evolution of features
Lab diagnosis of typhoid fever
salmonella typhi or paratyphi
culture blood, urine and stool
culture bone marrow??
Treatment of typhoid fever
oral azithromycin IV ceftriaxone (complicated)
What mosquito transmits dengue fever?
aedes aegypti
onset of symptoms of dengue fever
sudden onset of
- fever
- arthralgia and myalgia
- headache and retroorbital pain
signs of dengue fever
macular/maculopapular rash
haemorrhagic signs - petechiae, purpura, +ve tourniquet test
tourniquet test
capillary fragility
4 clinical diagnostics of dengue fever
thrombocytopenia
leucopenia
high transaminases
+ve tourniquet test
2 lab diagnosis of dengue fever
PCR and serology
Complications of dengue fever
dengue haemorrhagic fever
dengue shock syndrome
3 Treatments of complications of dengue fever
IV fluids
fresh frozen plasma
platelets
2 ways to prevent dengue fever
avoid bites
new vaccine dengvaxia (2016)?
3 causative organisms of schistosomiasis
s. haematobium
s. mansoni
s. japonicum
What animal is used in the transmission of schistosomisasis?
fresh water snails
5 stages of schistosomisasis
swimmers itch (hrs) invasive stage (>24hrs) katayama fever (15--20 days) acute disease (6-8 weeks) chronic disease
invasive stage of schistosomisasis signs
cough
splenomegaly
abdominal pain
katayama fever of schistosomisasis signs
fever
urticaria
diarrhoea
Lymph nodes
acute disease schistosomisasis signs
eggs in bowel or bladder
diagnosis of schistosomisasis
clinical
antibody tests
ova in stools and urine
rectal snip
Treatment of schistosomisasis
praziquantel
prednisolone if severe
signs of rickettsiosis
tick bite
amculopapular rash
2 causative organisms of rickettsiosis
R. conorii
R. africae
clinical features of rickettsiosis
swinging fever confusion bleeding headache endovasculitis rash
How is rickettsiosis diagnosed?
clinical features and serology
management of rickettsiosis
tetracycline
List some viral haemorrhagic fevers
ebola
CCHF
maximum incubation of VHF?
3 weeks
treatments of viral haemorrhagic fevers
isolation
supportive
what type of virus is zika?
flavivirus
Mosquito in zika and when they bite
aedes mosquito
daytime
How else can zika be transmitted?
sexual contact and blood transfusion
What other infections is zika related to?
dengue fever and yellow fever
clinical features of zika
headache rash fever malaise joint pains conjunctivitis
What can zika cause in pregnancy?
microcephaly and neurological problems
What can zika virus cause?
guillian barre syndrome
treatment for zika virus
no antivirals
mosquito control measures
vaccines in development
History in a returning traveller with fever
tropical area? precautions? risk? symptoms? incubation period
Infections causing a rash
typhoid, typhus and dengue
Infections causing jaundice
hepatitis, malaria, yellow fever
Infections causing LN
leishmaniasis and trypanosomiasis
infections affecting the liver
malaria, typhoid, amoebic abscess
Infections affecting the spleen
visceral leishmaniasis, typhoid, malaria
Investigations for fever in returning traveller
FBC malaria blood films LFT CXR blood culture stool microscopy and culture urinalysis and culture
Treatment for fever in returning traveller
Isolation - PPE?
supportive measures
empirical treatments
specific treatment
