Travel Infections

Question 1

What is the vector for malaria?

Answer 1

female Anopheles mosquito

Question 2

What are the five species of malaria and which one is the potentially harmful one?

Answer 2

Plasmodium falciparum is potentially harmful
Plasmodium vivax 
Plasmodium ovale 
Plasmodium malariae
Plasmodium knowlesi

Question 3

What are the signs and symptoms of malaria?

Answer 3

fever
rigors
aching bones
abdominal pain
headache
dysuria
frequency
sore throat
cough
splenomegaly
hepatomegaly
mild jaundice

Question 4

What are some complications of malaria?

Answer 4

Cerebral malaria (encephalopathy)- non-immune visitors, children in endemic areas hypoglycaemia, convulsions, hypoxia
Blackwater fever-severe intravascular haemolysis, high parasitaemia, profound anaemia, haemoglobinuria, acute renal failure
Pulmonary oedema
Jaundice
Severe anaemia
Algid malaria - Gram-negative septicaemia

Question 5

What are the diagnostic tests for malaria?

Answer 5

Thick & thin blood films-Giemsa, Field’s stain
Quantitative buffy coat (QBC)-centrifugation, UV microscopy
Rapid antigen tests-OptiMal, ParaSight-F

Question 6

What is complicated malaria?

Answer 6

One or more of…

Impaired consciousness or seizures 
Hypoglycaemia
Parasite count>2%
Haemoglobin<8mg/dL
Spontaneous bleeding / DIC
Haemoglobinuria 
Renal impairment or pH <7.3
Pulmonary oedema or ARDS
Shock (algid malaria) -Gram negative bacteraemia

Question 7

What are some treatments for uncomplicated malaria?

Answer 7

Riamet ® (artemether-lumefantrine) 3 days
Eurartesim ® (dihydroartemisinin-piperaquine) 3 days
Malarone ® (atovaquone-proguanil) 3 days
Quinine 7 days (S/E nausea, tinnitus, deafness, rash, hypoglycaemia) plus oral doxycycline (or clindamycin)

Question 8

What are the treatments for complicated malaria?

Answer 8

IV artesunate (unlicensed in UK) 
IV quinine (S/E cardiac depression, cerebral irritation, N&V) plus oral doxycycline (or clindamycin)

Question 9

What are the treatments for P. vivax, P. ovale, P. malariae, P. knowlesi?

Answer 9

chloroquine 3 days
Riamet ® (artemether-lumefantrine) 3 days
add primaquine* (14 days) in vivax and ovale, to eradicate liver hypnozoites

Question 10

What are the two causative organisms of enteric/typhoid fever?

Answer 10

Salmonella typhi
Salmonella paratyphi
Found in poor sanitation and drinking water

Question 11

What are the clinical features of typhoid fever?

Answer 11

1st week: fever, headache, abdo. discomfort, constipation, dry cough, relative bradycardia, neutrophilia, confusion
2nd week: fever peaks at 7-10 days, Rose spots, diarrhoea begins, tachycardia, neutropenia
3rd week (Complications): intestinal bleeding, perforation, peritonism, metastatic infections
week 4 (Recovery): 10 - 15% relapse

Question 12

What is the incubation period for typhoid fever?

Answer 12

Incubation period: 7 days - 4 week

Question 13

What are the diagnostic tests for typhoid fever?

Answer 13

Culture blood, urine & stool

Culture bone marrow

Question 14

What is the treatment for typhoid fever?

Answer 14

Oral Azithromycin now drug of choice for Asian-acquired, uncomplicated enteric fever
IV Ceftriaxone if complicated, or concerned regarding absorption

Question 15

What virus causes Dengue?

Answer 15

Arbovirus

Question 16

What is the transmission of Dengue virus?

Answer 16

Aedes aegypti

Question 17

What are the symptoms of Dengue virus?

Answer 17

Sudden fever
Severe headache, retro-orbital pain
Severe myalgia and arthralgia
Macular/ maculopapular rash
Haemorrhagic signs: petechiae, purpura, positive tourniquet test

Question 18

What are the tests for diagnosis of Dengue Virus?

Answer 18

Clinical 
Thrombocytopenia
Leucopenia
Elevated transaminases
Positive tourniquet test

Laboratory: PCR, serology

Question 19

What are some complications of Dengue Virus?

Answer 19

Dengue haemorrhagic fever (DHF)

Dengue shock syndrome (DSS)

Question 20

How is Schistosomiasis transmitted?

Answer 20

Snails in freshwater (such as in Malawi)

Question 21

What are the three types of schistosomiasis?

Answer 21

S. haematobium
S. mansoni
S. japonicum

Question 22

What is the presentation of schistosomiasis?

Answer 22

Swimmers Itch (1st few hrs)
clears 24-48hrs
Invasive stage (after 24hrs)
cough, abdo discomfort, splenomegaly, eosinophilia
Katayama Fever (after 15-20 days)
prostrate, fever, urticaria, lymphadenopathy, splenomegaly, diarrhoea, eosinophilia
Acute disease (6-8 weeks)
eggs deposited in bowel (dysentery) or bladder (haematuria)
Chronic disease

Question 23

How is schistosomiasis diagnosed?

Answer 23

Clinical diagnosis
Antibody tests
Ova in stools and urine
Rectal snip

Question 24

What is the treatment for schistosomiasis?

Answer 24

Praziquantel 20mg/kg, two doses 6hrs apart

Prednisolone if severe

Question 25

What are the causative organisms of Tick typhus?

Answer 25

Rickettsiosis

R. conorii, R. africae

Question 26

What is the presentation of tick typhus?

Answer 26

Abrupt onset swinging fever, headache, confusion, endovasculitis, rash (macular, petechial), bleeding

Question 27

Where is tick typhus commonly imported into the UK from?

Answer 27

Southern Africa, Mediterranean, Arabian Gulf

Question 28

How is tick typhus diagnosed and managed?

Answer 28

Diagnosed by clinical features, serology

Managed with tetracycline

Question 29

What is the type of virus that causes Zika and how is it transmitted?

Answer 29

Flavivirus
Transmitted by daytime-biting Aedes mosquitos
Also by sexual contact, blood transfusion
Related to dengue, yellow fever, Jap B encephalitis and West Nile viruses

Question 30

What is the presentation of Zika virus?

Answer 30

Clinical: no or mild symptoms - headache, rash, fever, Malaise, conjunctivitis, joint pains (like dengue)
In pregnancy, can cause microcephaly and other neurological problems
Can cause Guillain-Barre syndrome