Malaria prevention Flashcards
list the different organisms causing malaria malaria
there are 100s of plasmodium species but only 5 causes malarial disease in humans :
- P.falciparum
-P.vivax
-P.malaria
-P.ovale
-P.knowlesi
why does sickle-cell anemia protects against malaria ?
P vivax attaches to the red blood cells by Duffy antigen and the people with sicle-cell anemia do not have this receptor in their red blood cells
explain the life cycle of the malaria parasite
-plasmodium -infected female anopheles mosquito hunts for blood meal in the evening and through the night
- bites a person
the Plasmodium is in a stage of development called the sporozoite waiting patiently in the mosquitos salivary gland .
-through the bite ,sporozoites spill out of the mosquito saliva and make it into the bloodstream .
- the sporozoites reach the liver and mount an attack on the hepatic parenchymal cells= where they start asexual reproduction
-at this point the Plasmodium species vary a bit over the next one to two weeks Plasmodium falciparum plasmodium, malariae and Plasmodium Knwolese->sexual reproduction
- it’s generally asymptomatic
->released into the blood and they infect RED (undergoe other 3transformational changes and asexual reproduction inside the cell)->early trophozoite(ring)->late tropozoite->schizont
- mitosis ->defferentiation into merozoites -> get released to blood ->some merozoites undergo gametogony
- another mosquito takes a bite o the infected person
which places are high risk of malaria or hae high prevence
- SubSaharan countries ->very high risk
-mostly countries at are at the equator
Malaria risk in South Africa : - low risk - eastern Mpumalanga (Northern KZN)
- moderate risk - North eastrern Limpopo (among other things that side we are close to other countries that are very high risk such as Mozambique and Zim the boarder is a bit leaky 😅)
- KZN really tried to eliminate malaria and they seem to be effectie in thier measures
which are people are at risk ?
-Travelers( 80% took no prophylaxis and
Of those that took prophylaxis, only 25% took it appropriately)
Most common travel destination – Mozambique
- People living in endemic areas
In South Africa, mainly north-eastern Limpopo and eastern Mpumalanga (northern KZN)
High risk groups :
- people located in endemic areas
-pregnant women
-children under 5
- people with other comobidities e.g HI+
In South Africa when does the risk of Malaria increases andd what is recommanded during this time ?
- June to August ->low risk places ->Only non-drug measures recommended ->places such Mpumalanga ,KZN
- September to May->MODERATE RISK ->Where malaria chemoprophylaxis is indicated. mefloquine, OR atovaquone-proguanil, OR doxycycline should be used in addition to non-drug measures from .-> (Limpopo)
Which non drug measures can one take against malaria?
- Remain indoors between dusk and dawn
- Wear long, light coloured clothing
3.Screen doorways and windows
4.Apply a DEET-containing repellent (repeat every 4-6h if outdoors) the recommanded strength is 20%-50%-> stick ,cream ,lotion and aerisol from brands like Tabard, Peaceful Sleep and Mylol.
- most effective spray is from Tabard.30%
-both peaceful sleep and tabard’s stick is 35%
lotion and cream are useless<20% - Use mosquito mats & coils,
- Use (long-lasting) insecticide-treated bed nets & IRS sprayed accommodation.
7.Spray aerosol insecticide . - Use ceiling fans /air conditioner
name the 3 chemoprophylaxis for malaria
1.Atoaquone-proguanil(S2)
2.DOXYCYCLINE (S2)
3. Mefloquine(S4)
( these are effective if the person is adharent , and ALWAYS use non-drug measures to avoid mosquito bites )
How long does someone have to take the malaria chemoprophylaxis and how frequent ?
they vary ,
ATOVAQUONE-PROGUANIL (S2):
-frequency -> daily
-start -> 1-2 days before travel.
-continue until-> 7 days after leaving malaria area
DOXYCYCLINE S2:
-frequency ->daily
-start ->1-2 days before travel
-continue until->4 weeks after leaving malaria area
MEFLOQUINE S4:
-frequency -> Weekly
-start -> 1-2 weeks before travel
-continue until-> 4 weeks after leaving malaria area .
what are the most common ADR to Mefloquine ? and special precautions ?
ADR:
-nausea
-strange dreams
-dizziness
-mood changes
-insomnia
-headache
-diarrhoea
SPECIAL PRECAUTION :
-Avoid if requires fine motor coordination
what are the most common ADR to Doxycycline ? and special precautions ?
-Photosensitivity
-Oesophageal ulceration
-GIT symptoms
-Candida super-infections (GIT/ vaginal)
SPECIAL PRECAUTIONS:
-Sunscreen
-Take with a full glass of water
-Don’t lie down for 1 hr after dose
( for the GIT sx, the drug will be better when taken with food or water ->increase absorption ->fewer side effects )
what are the most common ADR to Atovaquone proguanil ? and special precautions ?
ADR :
(Well tolerated)
-Headache
-Mouth ulcers
-Stomatitis
-Abdominal pain
SPECIAL PRECAUTIONS:
Take with water / food for better absorption
for the GIT sx, the drug will be better when taken with food or water ->increase absorption ->fewer side effects )
from people in vulnerable groups where can Mefloquine be used and where not to use it ?
- pregnacy : use
2.breastfeeding : use
3.children : use >5 years
4.HIV+: potential drug interaction
5.Epilepsy : contraindicated
6.psychiatric conditions : contraindicated (even if only as a medical history )
7.renal /hepatic impairment : contraindicated in severe hepatic impairment .
8.Diabetics ( monitor glucose levels): use
from people in vulnerable groups where can Atovaquone-proquanil be used and where not to use it ?
- pregnancy: drug interaction
- breastfeeding: USE? (CDC if >5kg baby)
- children : >11kg
4.HIV+:potential drug interactions - Epilepsy: USE
- psychiatric conditions: USE
- renal /hepatic impairment: contraindicated (GFR<30ml/min)
- Diabetics ( monitor glucose levels): USE
from people in vulnerable groups where can Doxycycline be used and where not to use it ?
- pregnancy: contraindicated
- breastfeeding: use?(is it allowed if the trip is short )
- children :> 8 years
4.HIV+:USE - Epilepsy: USE (but there are drug interactions)
- psychiatric conditions: USE
- renal /hepatic impairment: USE
8.Diabetics ( monitor glucose levels): high insulin-related hypoglycaemia
