Infection 8 Travel Related Infections + Neglected Tropical Diseases

Question 1

Why are neglected tropical diseases classified as neglected?

Answer 1

Almost absent from global health agenda
Little funding
Associated stigma + social exclusion

Question 2

What questions need to be asked when a travel related infection is suspected?

Answer 2

Where have they been?
When were they there? Incubation time
Symptoms
Any idea on how they got the infection
Vaccinated?
Others in group unwell?

Potential diseases in that area

Question 3

What are the five species of malaria which affect humans?

Answer 3

Plasmodium falciparum
Plasmodium vivax
Plasmodium ovale
Plasmodium malariae
Plasmodium knowlesi

Question 4

What is the most severe species of malaria?

Answer 4

Plasmodium falciparum

Question 5

What is the vector for malaria?

Answer 5

Female Anopheles mosquito

Question 6

Incubation period of malaria

Answer 6

Minimum 6 days

Plasmodium falciparum can be 4 weeks
Plasmodium vivax/ovale can be 1 year

Question 7

What can the incubation period of plasmodium falciparum be?

Answer 7

4 weeks

Question 8

What can the incubation period of plasmodium vivax/ovale be?

Answer 8

Up to 1 year

Question 9

What type of organism is plasmodium?

Answer 9

Protozoa

Question 10

Investigation needed for suspected malaria

Answer 10

Blood film x3 - thick + thin smears
Blood tests - FBC, U+E, LFT
CXR - chest x ray
Head CT

Question 11

Management of malaria

Answer 11

Removal of vector - bed nets, sanitation
Drugs - artesunate, quinine (IV/PO), doxycycline, primaquine (liver related malaria)

Question 12

Drugs used to treat malaria

Answer 12

Artesunate IV or IM
Along side - Quinine
- Doxycycline

Primaquine - liver related malaria*

Question 13

What drug should be given for liver related malaria?

Answer 13

Primaquine

Question 14

What drug shouldn’t be used for malaria from plasmodium falciparum?
Why?

Answer 14

Chloroquine
Widespread resistance

Question 15

Who should you not give primaquine to?

Answer 15

G6PD patients

Question 16

What is the most common species of plasmodium causing malaria?

Answer 16

Plasmodium falciparum

Question 17

Presentation of malaria

Answer 17

High heart rate
Low BP
O2 sats 90%
Mild confusion
Bite/puncture mark
Hepatosplenomegaly
Vomiting + nausea
Fever
Headache
Fatigue
Sweating + chills
Dry cough

Question 18

Describe the life cycle of plasmodium falciparum

Answer 18

1- female anopheles mosquito bites human
2- injects sporozoites
3- sporozoites infect hepatocytes
4- sporozoites mature to merozoites
5- merozoites burst out of cell + infect bloodstream
6- merozoites attack erythrocytes
7- plasmodium asexually replicate and mature in RBCs
8- merozoites burst out of erthyrocytes (schizont)
9- process repeats

Question 19

What is a schizont?

Answer 19

Name of erythrocyte when merozoites are ready to burst out of them

Question 20

Name of erythrocyte when merozoites are ready to burst out of them

Answer 20

Schizont

Question 21

What is incubation time?

Answer 21

Time from when a person becomes infected until they start to see the onset of symptoms

Question 22

What causes a fever?

Answer 22

Cytokine release
Pyrogens

Question 23

What are paroxysm fever?

Answer 23

Fevers that occur in short bursts

Question 24

How does malaria cause symptoms of haemolytic anaemia?
What is the exception?

Answer 24

Destruction of erthyrocytes

Plasmodium falciparum doesnt

Question 25

Symptoms of haemolytic anaemia

Answer 25

Pallor Jaundice Dark coloured urine Weakness Dizziness confusion

Question 26

What is icterus?

Answer 26

Yellow eye - jaundice

Question 27

Prevention of malaria

Answer 27

Insecticide spray Clothing that covers whole body Mosquito nets Avoid still lakes Chemoprophylaxis

Question 28

Why should you avoid still lakes to prevent malaria?

Answer 28

Anopheles mosquitos lay eyes in stagnant water

Question 29

What are the categories for recurrent malaria?

Answer 29

- **Recrudescence** - parasite not killed - **Relapse**- cleared merozoites, dormant hypnotises in liver are no longer dormant - **Reinfection** - cured but new case

Question 30

Blood test result of malaria

Answer 30

Low WBC, platelets + Hb High urea, bilirubin, CRP

Question 31

Why does malaria cause by plasmodium falciparum not cause haemolytic anaemia?

Answer 31

1- P. falciparum creates sticky protein 2- protein coats surface of RBCs 3- RBCs clump together + occlude blood vessels 4- organ ischaemia

Question 32

What is Legionellosis?

Answer 32

Collection of conditions caused by Legionella bacteria

Question 33

What is the gram stain of Legionella bacteria?

Answer 33

Gram negative

Question 34

Most likely place of infection for Legionnaire’s disease Examples

Answer 34

Where the water is at a temperature high enough to help bacteria grow *e.g. poorly maintained shower system, AC unit*

Question 35

Mode of transmission of Legionella bacteria

Answer 35

Inhalation of droplets of water

Question 36

Incubation of legionnaire’s diease

Answer 36

2-10 days

Question 37

Initial signs and symptoms of Legionnaire’s disease

Answer 37

Headache Muscle/chest pain Chills Fever >40°

Question 38

Progressive signs and symptoms of Legionnaire’s disease

Answer 38

Cough Shortness of breath Nausea Vomiting Diarrhoea Confusion

Question 39

Treatment of Legionnaire’s disease

Answer 39

Antibiotics *clarithromyin*

Question 40

What is the microorganism that causes Legionnaire’s disease?

Answer 40

Legionella pneumophilia

Question 41

What other condition does Legionnaire’s disease commonly present similar signs and symptoms to?

Answer 41

Pneumonia

Question 42

What is the characteristic image in malaria blood film?

Answer 42

Headphone/wedding ring

Question 43

Where do plasmodium species remain dormant within the human body?

Answer 43

Liver

Question 44

What is schistosomiasis?

Answer 44

Genus of flatworm

Question 45

Transmission of schistosomiasis

Answer 45

Through unprotected skin contact in areas of fresh water contaminated with helminths released from snails

Question 46

What type of microorganisms is helminths?

Answer 46

Parasite

Question 47

Symptoms of acute schistosomiasis

Answer 47

Fever Diarrhoea Coughs Rashes Abnominal pain Muscle + joint pain

Question 48

Result of chronic inflammation associated with schistosomiasis

Answer 48

Damage due to host’s immune response - anaemia - cystitis - CVS + respiratory issues - neurological - seizures, dizziness

Question 49

Diagnosis of schistosomiasis

Answer 49

Confirmed by finding eggs in urine or stool sample Blood test for antibiotics

Question 50

Treatment of acute schistosomiasis

Answer 50

Steroids - reduces inflammation

Question 51

Treatment of schistosomiasis

Answer 51

*praziquantel*

Question 52

What is *praziquantel* used for and when is it most effective (what does this mean)?

Answer 52

- To treat schistosomiasis - Most effective once worms have matured - Patients often aren’t given treatment until a number of weeks post infection

Question 53

What is another name for typhoid fever?

Answer 53

Enteric fever

Question 54

Cause of typhoid fever

Answer 54

Salmonella typhi

Question 55

What type of microorganism is Salmonella typhi?

Answer 55

Bacteria Rod shaped Gram negative

Question 56

Gram stain of Salmonella typhi

Answer 56

Rod shaped gram negative

Question 57

Presentation of typhoid fever

Answer 57

Fever Abdominal pain Constipation If left untreated: Delirium GI haemorrhage Bowel perforation

Question 58

Where is typhoid fever most common?

Answer 58

Where there is poor sanitation and limited access to clean water

Question 59

Who are more susceptible to typhoid fever and why?

Answer 59

Children Immune systems are still developing

Question 60

Treatment of mild typhoid fever

Answer 60

IV *Ceftriaxone Cephalosporin Azithromycin Macrolide* At home

Question 61

Treatment of serious typhoid fever

Answer 61

Infections of antibiotics in hospital

Question 62

Vaccinations of typhoid fever

Answer 62

1 injections or 3 tablets

Question 63

What is dengue fever cause by?

Answer 63

Dengue virus

Question 64

Transmission of dengue virus

Answer 64

Mosquitoes

Question 65

Presentation of dengue

Answer 65

Mild or asymptomatic Intense headache Fever Widespread red rash Muscle/joint pain

Question 66

Treatment of dengue

Answer 66

No specific treatments Normally resolves itself within a few days Supportive treatments - paracetamol - take plenty of fluids

Question 67

Treatment of severe dengue

Answer 67

No treatment Intensive care required - IV fluids - O2 if needed - blood transfusion - platelet transfusion

Question 68

Symptoms of severe dengue

Answer 68

Restlessness Acute fever Severe abdominal pain Petechiae - due to low platelets Nosebleeds Large decrease in BP - shock

Question 69

Why would aspirin and NSAIDs make dengue worse?

Answer 69

COX enzymes are blocked Needed to help with clotting