Travel related infections ad NTD's Flashcards
Apply the infection model to a patient presenting with an infection linked to travel (7)
- Where have they been?
- What are the potential diseases in that area
- When were they there? Incubation time
- What symptoms have they had?
- How might they have gotten the infection?
- Prophylaxis/vaccinations Others in group unwell?
- There might be specific important information that can give us a clue – such as elevated IgE or eosinophils in helmith infections.
Expand the description of pathogen/person/practice/place as it applies to travel related infections
Why are travel histories important?
- recognise imported (and rare) diseases
- there are different strains of pathogen (impacts on protection/detection)
- infection prevention
Different strains - present differently
Antibiotic resistance (less strict policies)
Prevent infection (to ward and lab workers) - come back to
➢ Very many travel related infections
➢ Specific to certain areas (place) or activities
➢ Recognise imported diseases (rare/unknown) in
the UK
➢ Different strains of pathogen
(antigen/resistance)
➢ Infection prevention (ward/lab)
What is the malaria vector?
Female Anopheles mosquito
What are the 5 main species of plasmodium in order of the most common organism?
5 main species of Plasmodium (protozoa):
- Plasmodium falciparum - most severe form
- resistance emerging
- Plasmodium vivax - usually less severe & relapsing
- Plasmodium ovale - usually less severe & relapsing
- Plasmodium malariae - relatively mild
- Plasmodium knowlesi - macaque monkeys – zoonotic transfer
Symptoms of malaria (10)
- Confusion
- Fever
- Chills
- Sweating
- Headache
- Seizures
- Haemoglobinuria (excretion of free haemoglobin in the urine)
- Vomiting
- Nausea
- Dry cough
Signs of malaria (5)
- Splenomegaly (to remove destroyed RBCs)
- Hepatomegaly (infection there)
- Jaundice
- Bite marks
Lifecycle of malaria
- Female mosquito bites a human
- She injects sporozoite into human bloodstream
- They make their way to the liver and infect liver cells
- The parasite develops into schizonts, creating loads of merozoites
- These merozoites burst out of the cell and journey back towards the bloodstream
- The mezozoites infect healthy red blood cells and reproduce in them
- Eventually, they rupture the cell and more meozoites are released into the blood stream and infect other cells
- Leads to the mass destruction of red blood cells
- A few of the infected cells develop into gametocytes, which can remain in the blood stream for several days and may be ingested by another mosquito during a subsequent feeding
- Inside the mosquito, the gametocytes develop into new sporozoite
Investigations of malaria (4)
- Blood film (thick and thin smears) x3
- Blood test: FBC, U&E, LFT, glucose, coagulation
- CXR - pulmonary oedema?
- CT of Head if neurological symptoms - cerebral oedema?
Diagnosis of malaria process
What are the options for management of malaria?
- Removal of vector (mosquito)
- Drugs
How can you remove the vector for malaria? (5)
- Bed nets
- Sanitation facilities
- Sprays
- Mesh windows
- Larvacides
Severe complications of malaria
What drugs can be used for malaria?
artesunate, quinine (IV/PO), doxycycline. Don’t use chloroquine (unless for P.vivax). Primaquine is given for liver-related malaria. (However, you don’t give this for G6PD patients – why? Relate this back to MEH
module!).
Form a differential diagnosis based on region of travel, incubation period
and clinical presentation
Lecture 2 of today, practice and get familiar with the symptoms of each and locations of travel and incubation period
