CHAPTER 4: MALARIA IN PDW

Question 1

Where are %% of malaria incidences observed.

Answer 1

90% In Africa.

Question 2

How may deaths a year are attributed to malaria.

Answer 2

400,000 deaths each year.

Question 3

How much does antimalarial drugs cost.

Answer 3

<$1

Question 4

What are the four countries that account for almost half the malaria deaths worldwide.

Answer 4

Nigeria.
Democratic Republic of Congo.
Tanzania.
Niger.

Question 5

What are the two patient populations we are most concerned about when thinking about Malaria.

Answer 5

Mother/Pregnant women.
Children under the age of 5.

Question 6

What are the complications associated with pregnant woman contracting malaria infection.

Answer 6

Placental malaria, plasmodium falciparum infected erythrocytes sequester in the placenta, resulting in maternal anaemia and also puts the mother at risk of death before and after childbirth.

Question 7

(a) Describe briefly malaria life cycle in the liver and erythrocyte; (b) What stage is responsible for the clinical presentation of malaria symptoms.

Answer 7

a. In the liver cells, sporozoites infect the cells and undergo maturation that leads to the release of merozoites.
In the blood, erythrocytes are infected by merozoites which later becomes trophozoite. Trophozoite reproduce asexually and later the hemolysis leads to release of merozoites.
b. Symptoms of anaemia and fever is due to hemolysis and release of parasite in the blood.

Question 8

What is the %% of children that account for Malaria death in Africa.

Answer 8

80% deaths attributed to children under age of 5, according to WHO malaria report 202

Question 9

How is malaria transmitted.

Answer 9

Migrant workers e.g. Gold mining North East Myanmar.
Seasonal workers (farming). For example, seasonal workers who are carrier that transport parasites to the highlands and other location in Ethiopia where there is lower malaria prevalence.
Troops.

Question 10

Which method is a quantitive in diagnosis of malaria.

Answer 10

Molecular methods such as PCR: expensive but accurate.

Question 11

Which method is qualitative in diagnosis of malaria.

Answer 11

Antigen test ‘dipsticks’

Question 12

What intervention in the future could lead to better diagnosis.

Answer 12

In mobile devices there is an inserted chip that could detect disease.

Question 13

What are the drawbacks (figure associated) with subjective diagnosis vs blood film.

Answer 13

Subjective diagnosis leads to misdiagnosis and poorer patient prognosis. For example Malawi, one study showed that when clinical predicators (rectal temperature, nailbed pallor, and splenomegaly) were used as treatment indications, rather than using only a history of subjective fevers, a correct diagnosis increased from 2% to 41% of cases.

Question 14

Fill the table for Malaria treatment, prevention and eradication.

Answer 14

Question 15

List the malaria drugs.

Answer 15

Quinine derivatives
• Aminoquinolones: Primaquine , Chloroquine
• DiHydroFolate (DHF) inhibitors
• Artemesinin Combination Products (ACT’s)

Question 16

What are the limitations associated with antimalarial drugs.

Answer 16

Compliance
Cost
Safety
GMP Counterfeit
Resistance.

Question 17

What are the limitations associated with antimalarial drugs concerning safety: THINK DEFICIENCY.

Answer 17

Primaquine derivatives: Not effective in patient with G6PD deficiency because it causes hemolysis.

Question 18

What are the limitations associated with antimalarial drugs concerning cost: THINK EXPENSE/POTENTIAL.

Answer 18

Malarone (fixed-dose combination): Too expensive to distribute and patient population in Africa don’t have the financial means to afford treatment or healthcare system that pays for it. Also there is resistance potential.

Question 19

What is the limitation of antimalarial drugs concerning course of treatment, PK, cost.

Answer 19

Anti-malarial combination is it tends to be long course, which again for patient population can be costly/not viable in their impoverished circumstances, and short half-life, for example artemisinin (1.4-2.6 h), means there is now no anti-malarial coverage over days which would be ideal.

Question 20

What are the limitations associated with antimalarial drugs concerning drug resistance (6 factors).

Answer 20

Question 21

What is your ideal antimalarial drug.

Answer 21

Short course (<3 days), full day coverage, OD administration, easily accessible form e.g. dispersible tablets for 5 year olds. (<$1 manufacture).

Question 22

What are the potential damage of self medicating at Medicine Sellers e.g. Africa Village Stalls (DDCQ).

Answer 22

Incorrect Diagnosis, Incorrect Dosing, Poor Compliance, Poor Quality medicines.

Question 23

How could self-medication at Medicine sellers be addressed: solution.

Answer 23

Solution employed by Indian government involved the setting up of specialised medical centres with specialist volunteers that can DDCQ: Diagnose, Dose correctly, help with Compliance, and provide Quality medicines.

Question 24

a. How can Malaria be prevented (3 methods, memorise). b. What is covered in the classes.

Answer 24

1. Vector Control.
2. Preventative Chemotherapy.
3. Vaccine.

Question 25

What does seasonal malaria chemoprevention contain.

Answer 25

Sulfadoxine-pyrimethamine (SP).

Question 26

What has been the age extension of seasonal malaria chemoprevention and what have been the benefit.

Answer 26

Extending the SMC age range up to 10 years of age effective in Senegal with high coverage and impact.

Question 27

What is seasonal chemoprevention

Answer 27

Community-based intervention to prevent malaria in those most vulnerable to the disease’s effects (e.g. <5 years). It involves administering monthly courses of antimalarial medicines during peak malaria transmission season.

Question 28

What is mass administration chemoprevention

Answer 28

Involves giving treatment to an entire population or every person in a geographical area regardless of ascertainment of disease or infection status.

Question 29

What is classed in IRS.

Answer 29

IRS: Indoor Residual Spraying.
Indoor: Room Surfaces.
Outdoor: Larvicides onto stagnant water (surfactant).

Question 30

What is classed in ITN.

Answer 30

Bed nets.
Long-lasting insecticide treated nets (LLTN).

Question 31

For vector control: what are the the drugs used to impregnante bed nets and used in IRS.

Answer 31

Question 32

What are the issues associated with insecticides.

Answer 32

Insecticide resistance.
Pyrethroid resistance is occurring major malaria vector Anopheles in Africa.

Question 33

What are the genes involved in pyrethroid resistance.

Answer 33

Mutations on the gene encoding for the sodium channel, knockdown resistance (kdr) cause resistance to DDT and/or pyrethroid insecticides.

Question 34

How can insecticide resistance be combated.

Answer 34

Rotating insecticides.
Using combination of ITN non-pyrethroid + pyrethroid.
Mosaic nets instead of plastic nets impregnted with pyrethroid.

Question 35

What is an example of ITN non-pyrethroid + pyrethroid.

Answer 35

Piperonyl butoxide + pyrethroid.

Question 36

What does education vector control involve.

Answer 36

Trained healthcare professionals such as pharmacist, nurses, doctors to volunteer in teaching population of how to use bed nets, indoor spraying insecticides and when to seek medical help when symptoms of malaria arise.

Encouraging and educating pregnant women to seek antenatal care where they educate why preventative chemotherapy is required to prevent malaria causing deleterious effects to them.

Teaching school children on what malaria is and what to avoid- puddles, leakages

Question 37

What is the requirement for an effective vaccine for preventing malaria.

Answer 37

Malaria vaccine with protective efficacy if more than 80% against clinical disease and last longer than four years.

Question 38

Why is there no widely effective vaccine yet for Malaria.
( Look at My Whole Family)

Answer 38

Question 39

What is the name of the vaccine in pilot trial in Ghana, Kenya and Malwai fo Malaria.

Answer 39

Mosquirix piloted by WHO for children aged 5 to 17 months.

Question 40

What is the potential downside Mosquirix.

Answer 40

Not pragmatic, as vaccine who need to be administered x 4 a year and that increases cost to African countries that may not be able to afford it.

Question 41

Whats the name of the vaccine with 450 participants that showed good efficacy for Malaria protection.

Answer 41

New Oxford Vaccine showed 77% efficacy in the high dose group in the trial report.

Question 42

Fill the table for the method used in eradication of malaria.

Answer 42

Question 43

What type of blood films are preferred: thin or thick films and why.

Answer 43

Thin films allow for species identifications whereas thick films pick up lower level of infection due to larger volume of blood. Also the parasite is distorted so it is difficult to distinguish species.