Malaria Flashcards
What is malaria?
Malaria is a disease caused by Plasmodium protozoa which is spread by the female Anopheles mosquito.
How many species of Plasmodium cause disease in humans?
There are four different species which cause disease in man.
What are the four species of Plasmodium that cause malaria?
The four species are Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, and Plasmodium malariae.
Which species of Plasmodium causes nearly all episodes of severe malaria?
Plasmodium falciparum causes nearly all episodes of severe malaria.
Which species of Plasmodium is the most common?
Plasmodium vivax is the most common species.
What type of malaria do the other three Plasmodium species cause?
The other three types cause ‘benign’ malaria.
What is a well-documented protective factor against malaria?
The protection from malaria that sickle-cell trait offers is well documented.
What are other protective factors against malaria?
Other protective factors include G6PD deficiency, HLA-B53, and absence of Duffy antigens.
Life cycle malaria parasite
What is Falciparum malaria?
Falciparum malaria is the commonest and most severe type of malaria.
What are the classical symptoms of Falciparum malaria?
The classical triad of symptoms includes paroxysms of fever, chills, and sweating.
How often do symptoms occur in Falciparum malaria?
Symptoms may occur every 48 hours corresponding to the erythrocytic cycle of the Plasmodium falciparum parasite.
What are common initial manifestations of Falciparum malaria?
Initial manifestations can include malaise, headache, and myalgia.
What is the hallmark symptom of malaria?
Fever is the hallmark of malaria, typically cyclical, often accompanied by sweating and sometimes rigors.
What gastrointestinal symptoms are associated with Falciparum malaria?
Anorexia, nausea, vomiting, and abdominal pain are frequent; diarrhea can occasionally occur, more commonly in children.
What respiratory symptoms may occur in Falciparum malaria?
Cough and, in some cases, mild tachypnoea may occur, though primary respiratory complications are rare in non-severe cases.
What neurological symptoms are common in Falciparum malaria?
Headache is prominent and often severe; dizziness and sleep disturbances may also be observed.
What cardiovascular symptoms may be present in Falciparum malaria?
Tachycardia may be evident; hypotension is more typical of severe malaria but can occasionally be seen in non-severe cases.
What haematological findings are significant in Falciparum malaria?
Thrombocytopaenia is the most significant finding and can occur in the absence of severe disease; mild anaemia may also be present.
What renal symptoms may occur in Falciparum malaria?
Mild to moderate increases in creatinine or blood urea nitrogen levels may be observed.
What are features of severe Falciparum malaria?
Features include schizonts on a blood film, parasitaemia > 2%, hypoglycaemia, acidosis, temperature > 39 °C, and severe anaemia.
What complications can arise from severe Falciparum malaria?
Complications include cerebral malaria (seizures, coma), acute renal failure, acute respiratory distress syndrome (ARDS), hypoglycaemia, and disseminated intravascular coagulation (DIC).
What is the first-line therapy for uncomplicated Falciparum malaria?
The 2010 WHO guidelines recommend artemisinin-based combination therapies (ACTs) as first-line therapy.
What are examples of artemisinin-based combination therapies?
Examples include artemether plus lumefantrine, artesunate plus amodiaquine, artesunate plus mefloquine, artesunate plus sulfadoxine-pyrimethamine, and dihydroartemisinin plus piperaquine.
What is the treatment for severe Falciparum malaria?
A parasite count of more than 2% will usually need parenteral treatment irrespective of clinical state.
What is the recommended treatment for severe Falciparum malaria?
Intravenous artesunate is now recommended by WHO in preference to intravenous quinine.
What should be considered if the parasite count is > 10%?
Exchange transfusion should be considered.
What does shock in severe Falciparum malaria indicate?
Shock may indicate coexistent bacterial septicaemia; malaria rarely causes haemodynamic collapse.
What is the most common cause of non-falciparum malaria?
The most common cause of non-falciparum malaria is Plasmodium vivax.
What are the other species that cause non-falciparum malaria?
Plasmodium ovale and Plasmodium malariae account for the other cases.
Where is Plasmodium vivax commonly found?
Plasmodium vivax is often found in Central America and the Indian Subcontinent.
Where is Plasmodium ovale typically found?
Plasmodium ovale typically comes from Africa.
What is another non-falciparum species that causes clinical pathology?
Plasmodium knowlesi is another non-falciparum species which causes clinical pathology.
Where is Plasmodium knowlesi predominantly found?
Plasmodium knowlesi is predominantly found in South East Asia.
What are the general features of malaria?
General features of malaria include fever, headache, and splenomegaly.
What is the fever cycle for Plasmodium vivax and ovale?
Plasmodium vivax and ovale cause cyclical fever every 48 hours.
What is the fever cycle for Plasmodium malariae?
Plasmodium malariae causes cyclical fever every 72 hours.
What syndrome is associated with Plasmodium malariae?
Plasmodium malariae is associated with nephrotic syndrome.
What stage do ovale and vivax malaria have that may cause relapse?
Ovale and vivax malaria have a hypnozoite stage and may therefore relapse following treatment.
What is the recommended treatment in chloroquine-sensitive areas?
In chloroquine-sensitive areas, WHO recommends either an artemisinin-based combination therapy (ACT) or chloroquine.
What should be used in chloroquine-resistant areas?
In chloroquine-resistant areas, an ACT should be used.
What should be avoided in pregnant women?
ACTs should be avoided in pregnant women.
What treatment should patients with ovale or vivax malaria receive after acute treatment?
Patients with ovale or vivax malaria should be given primaquine following acute treatment with chloroquine to destroy liver hypnozoites and prevent relapse.
