Malaria, Typhoid and Dengue Flashcards
What is Malaria?
Malaria is a parasitic infection caused by protozoa of the genus Plasmodium.
What is the epidemiology of Malaria?
Pregnant women and children aged under 5 years remain the most susceptible to disease in endemic areas.
Almost all cases of malaria in non-endemic areas are imported by people travelling from endemic areas, either as tourists or as migrants visiting friends or relatives. Each year, 25 million to 30 million people from the US and Europe travel to the tropics, of whom approximately 10,000 to 30,000 acquire malaria.
What is the aetiology of Malaria?
Risk factors for severe infection include low host immunity (i.e., individuals living in non-endemic areas), pregnancy, age <5 years, immunocompromise (e.g., underlying HIV infection), and older age.
During a blood meal, an infected female Anopheles mosquito injects 8 to 15 malarial sporozoites, which rapidly enter hepatocytes. Reproduction by asexual fission (tissue schizogony) takes place to form a pre-erythrocytic schizont. This part of the life-cycle produces no symptoms. After a period of time, 30 to 40 thousand merozoites are released into the bloodstream to penetrate erythrocytes after attaching via receptors.
What would you find in the history and exam of Malaria?
Fever, headache, myalgia, anorexia, diarrhoea, seizures, jaundice
What investigations would you do for Malaria?
Thick and Thin blood films with Giemsa stain
Rapid tests
FBC, clotting profile, U/E, Cr, LFTs, BMs, urinalysis, ABG
What is the management of Malaria?
Chloroquine phosphate
if unable to take oral: artesunate
What are the complications of Malaria?
AKI hypoglycaemia Metabolic acidosis Anaemia DIC Seizure
What is Typhoid?
Typhoid infection is a faecal-oral transmissible disease caused by the bacterium Salmonella enterica, serotype S typhi.
What is the epidemiology of Typhoid?
Highest incidence is in the Indian subcontinent and among travellers returning from that area.
Prolonged febrile illness with normal white blood cell count in returnees from an endemic area should increase suspicion.
What is the aetiology of Typhoid?
Humans are the only known reservoir, and transmission occurs through food and water contaminated by acutely ill or chronic carriers of the organism.
What would you find in the history and exam of Typhoid?
High fever Dull frontal headache Abdominal pain anorexia constipation cough diarrhoea Malaise Nausea
What investigations would you do for Typhoid?
Definitive diagnosis is by blood culture.
FBC, LFTs
Blood culture
Stool culture
Urine culture
Bone marrow culture
What is the management of Typhoid?
Ceftriaxone + Azithromycin
encephalopathy- steroids
What are the complications of Typhoid?
Typhoid hepatitis
Sepsis
Death
What is Dengue?
Notifiable disease. In dengue-endemic regions, suspected, probable, and confirmed cases of dengue infection should be reported to the relevant authorities as soon as possible.
