Travel related infections Flashcards
What are the 3 categories for incubation periods?
less than 10 days
10-21 days
21+ days
How can tropical infections be aquired?
- food/ water
- insect/ tick bite
- swimming
- sexual contact
- animal contact (bite/ safari)
- beach/ recreational activities
Which species of malaria are most common and where are they common?
- plasmodium falciparum is most common in africa
- plasmodium vivax and ovale are most common in india
What mosquito carries the malaria protozoa?
female anopheles
What is the incubation period of p. falciparum and p. vivax/ ovale?
falciparum: 6-12 days
p. vivax/ ovale: up to 1 yr + (usually 10-17 days)
What will be presentation of mild malaria?
- always have fever, other symptoms are more vague and variable
- headache
- dry cough
- muscular fatigue and pain
- chills and sweating
- nausia
- vomiting
- mild hepatoslenomagaly
What will be the presentation of a severe malarial infection?
- fluid in lungs
- Loss of liver function
- loss of renal function
- confusion, fits and seizures
- low/ normal WBC
- low platelets
- DIC
- acidosis
- hypoglycaemia
- tachycardia, arrthmias, hypotension
What investigations should be done for someone with malaria?
- 3 blood films (need 3 negatives to exclude it)
- FBC, U&E, LFTs, glucose and coagulaiton
- head CT if CNS symptoms
- CXR
What will be blood test and blood film results of someone with malaria?
- anaemia, low WBC and platelets (haemolytic anaemia makes spleen enlarge so more blood pools in spleen)
- LFT normal when mild
- urea and creatinine increase- renal injury
- bilirubin high (heamolysis)
- high CRP
- protozoa seen as dark purple dots within RBCs on blood film
Describe the life cycle of plasmodium falciparum
- Enter blood through mosquito as a sporozoite
- then go into hepatocyte and become a schizont
- which multiplies within hepatocyte and becomes a merozoite
- merozoite reproduce within the RBC and then destroy them by haemolysis
- merozoites travel in blood and in some RBCs become gametocytes which go back into mosquito when mosquito takes their blood
- in mosquito it matures into sporoziote
What is the result of a salmonella thyphi/ paratyphi infection?
thyphoid and paratyphoid (which is milder) - enteric fever
Where is enteric fever common and how is it aquired?
asia, some in africa and S america
- faecal oral from contaminated food and water
WHat is incubation period and symptoms of enteric fever?
7-14 days
- fever
- headache
- abdodiscomfort
- sometimes constipation, diarrohea or nothing
- dry cough
What is major complication of enteric fever?
intestinal haemorhagge and perforation
How is malaria treated?
If P. flaciparum: artesunate or quinine and doxycycline
If other: chloroquine (lots of resisstance to this) or primaquine (will destroy dormant protozoa in liver to stop reoccurance)
Can you have the same malarial infection twice?
Yes
although some ppl in afria how have lots of infections develop some immunity
Who is most at risk from malarial infection?
young, old and pregnant ppl
How is malaria prevented?
- bite prevention (nets, repellant, clothing)
- chemoprophylaxis- start before and continue after return (artesunate, quinine, chloroquinine, primaquine)
What is common disease in cambodia/ south asia causing fever, back pain, headache, widespread flat rash?
dengue fever- from mosquito
Where would you find info on travel infections?
WHO website, journal of infection
Where is MERS coronavirus common?
Middle east (Middle East Respiratory Syndrome)
What will be signs of MERs infection?
fever, cough, shortness of breath, consolidation on lungs (in CXR), roughly 14 days after travel to country, low blood O2
What infection commonly causes an itchy rash and then a week later high eosinophil count, low grade fever, lethargy, body ache, wheeze?
schistomiasis
