Malaria Intro

Question 1

Name the species of malaria parasite that infect humans

Answer 1

Plasmodium falciparum: killer
P. vivax: recurring disease
P. malariae: "benign", rare
P. ovale: recurring, rare
P. knowlesi, rare, killer, zoonosis

Question 2

Draw the erythrocytic asexual lifecycle

Answer 2

DO IT

Question 3

Describe and explain the distribution of the disease

Answer 3

The most important is ambient temperature and humidity (higher temperatures accelerate the parasite growth in the mosquito) and whether the Anopheles survives long enough to allow the parasite to complete its cycle in the mosquito host

Question 4

Explain how the parasite causes pathology

Answer 4

Pathological consequences are primarily associated with the destruction of erythrocytes leading to anaemia, vascular collapse, kidney failure.
In P. falciparum malaria, schizonts adhere to capillaries of internal organs and if the brain is involved, the damage caused by blockage and damage to capillaries leads to cerebral malaria which is fatal

Question 5

Discuss the challenges to malaria control

Answer 5

Insecticide resistance
Drug resistance
War
Population movements
Lack of funding
Lack of community participation
Scarce resources and socio-economic instability have hindered efficient malaria control activities

Question 6

List the options for diagnosis

Answer 6

Microscopy: the “gold standard”, time consuming and can only be performed by trained individuals. Stains + fluorescence

Serology: ELISA, immunoprecipitation

q/RT-PCR: several developed, most target the 18S rRNA gene of parasites. Very sensitive, the best can detect parasites 3 days before microscopy can

OptiMAL-IT
detection of pLDH - an enzyme in Plasmodium species’ glycolytic pathway - detected by both general specificity antibodies and specific monoclonal antibodies. Doesn’t give a positive reaction for human LDH. Differentiation of malaria parasite species is based on antigenic differences between the pLDH isoforms. Since pLDH is produced only by live Plasmodium parasites, this test has the ability to differentiate live from dead organisms

Question 7

What is the vector of malaria?

Answer 7

Female anopheles mosquito

Question 8

How many people per year does malaria infect/kill?

Answer 8

214 million people infected with P. falciparum in 2015
438,000 died in 2015 (90% in Sub-Saharan African)
Things are improving…
Between 2000-15, incidence fell by 37%, 42% in Africa
Malaria mortality rates fell by 60%, 66% in Africa in the same period