malaria Flashcards
what should you recommend to patients to improve protection unless they are sleeping in a well screened room, or if the room is fitted with functioning AC and sufficient well sealed into which mosquitoes cannot enter
- mosquito bed nets impregnated with pyrethroid insecticides e.g. permethrin
- vaporised insecticides are also useful
is prophylaxis absolute
no, breakthrough infection may occur
clothing that provide protection against bites
long sleeves, long trousers and socks worn after sunset
you advise a patient on what types of clothes to wear to protect them from getting bitten.
A: wear long sleeves and long trousers
B: wear socks after sunset
C: wear sunglasses and a hat
are all the above correct, or none correct, or single ones correct?
C is incorrect
A and B are correct.
which % % DEET-based insect repellant is recommended as the first choice?
A 50% DEET-based insect repellent is recommended as the first choice; there is no further increase in duration of protection beyond a DEET concentration of 50%.
In what age is DEET safe and effective when applied to the skin
adults and children over 2 months
should you advice patients to use DEET based insect repellant on their skin if they are pregnant of breastfeeding
yes you can use
however avoid ingestion
BF mothers to wash hands and breast tissue before handling infants
can also be used in children over 2 months
DEET first or suncream first?
DEET after suncream
does DEET reduce SPF of suncream?
yes. you need to apply DEET after suncream. ensure suncream of SPF 30-50
prophylaxis should be continued for …… after leaving the area (except atovaquone with proguanil HCl which should be stopped 1 week after leaving)
4 weeks after leaving
prophylaxis should be continued for 4 weeks after leaving the area, except for the following which should be stopped one week after leaving
atovaquone with proguanil hydrochloride
prophylaxis should be continued for 4 weeks after leaving the area, except for atovaquone with proguanil hydrochloride which should be stopped…
1 week after leaving
which drug can be used in pt requiring long term prophylaxis
chloroquine
however there is concern over the protective efficacy of chloroquine in certain areas where is was previously useful
which drug is licensed for use up to 1 year (although if tolerated in short term, no evidence of harm when used for up to 3 years)
mefloquine
mefloquine is licensed for use for up to …
1 year
how long can doxycycline be used for prophylaxis for
up to 2 years
how long can atovaquone with proguanil hydrochloride be used for prophylaxis for?
up to 1 year
it is important to consider that any illness that occurs within ….. and especially within ….. of return might be malaria, even if all recommended precautions were taken
if they develop any illness after their return, they should see a doctor early and specifically mention their risk of exposure to malaria
it is important to consider that any illness that occurs within 1 year and especially within 3 months of return might be malaria
is malaria a notifiable disease
yes
which drugs are unsuitable for prophylaxis in individuals with a history of epilepsy?
Both chloroquine and mefloquine
a patient is enquiring about malaria tablets before she goes on a trip with her family. she mentions that her daughter is on a lot of medications for epilepsy. which drugs can you not use for malaria prophylaxis in pt with history of epilepsy?
Both chloroquine and mefloquine
a patient is enquiring about malaria tablets before she goes on a trip with her family. she mentions that her daughter is on a lot of medications for epilepsy. you cannot use chloroquine and mefloquine in patients with a history of epilepsy. what are the alternatives?
doxycycline (but this can interact with some antiepiletpics and its dose may need adjustment)
atovaquone with proguanil
doxycycline can be used for malaria prophylaxis in pt with history of epilepsy. however, it interacts with some anti epileptics and its dose may need adjustment. name and explain some interactions
inducers:carbamazepine, phenytoin, barbiturates
these drugs DECREASE the concentration of doxycycline. adjust dose of doxy
patients with this condition are at particular risk of severe malaria. if travel to malarious area is unavoidable, rigorous precautions are required against contracting the disease.
asplenia - Asplenic individuals (or those with severe splenic dysfunction)
advice about travelling to malarious areas during pregnancy
should be avoided
if unavoidable, inform pt about risks and benefits of effective prophylaxis
this drug can be given during pregnancy, but not appropriate for most areas because their effectiveness has declined
chloroquine
what do you need to do if you give proguanil during pregnancy
give folic acid (dosed as a pregnancy at high risk of neural tube defects) for the length of time that it is used during pregnancy
dose is 5mg OD
if this drug is given during pregnancy, you must give adequate folate supplementation to the mother (dose is 5mg OD for the length of time it is used during pregnancy - high risk of neural tube defects)
proguanil
if a pregnant woman is travelling to high risk areas or there is resistance to other drugs, consider this drug in the 2nd and 3rd trimesters. it can be used in 1st trimester with caution if benefits outweigh risks.
mefloquine
use of doxycycline for prophylaxis during pregnancy
doxy is CI in pregnancy
however it can be used for malaria prophylaxis if other regimens are unsuitable, and if the entire course of doxy can be completed before 15 weeks gestation
doxycycline is contraindicated in pregnancy however it can be used for malaria prophylaxis if other regimens are unsuitable, and if the entire course can be completed before ….
before 15 weeks gestation
this combination should be avoided during pregnancy however it can be used during 2nd and 3rd trimester if no suitable alternative. you will also need to give folate supplementation during the length of time it is used during pregnancy (using 5mg which is the dose for pregnancy at high risk of neural tube defects)
Atovaquone with proguanil hydrochloride
travellers taking warfarin need to begin malaria chemoprophylaxis ….. before departure and their INR needs to be stable before departure
2-3 week before departure
when should warfarin INR be measured for pt taking chemoprophylaxis?
before starting chemoprophylaxis
7 days after starting
after completing course
who should carry emergency standby treatment (2)
Travellers on prophylaxis and visiting remote, malarious areas if they are likely to be more than 24h away from medical care
Also consider in long term travellers living in or visiting remote, malarious areas that may be far from appropriate medical attention - this does not replace the need to consider prophylaxis
in order to use standby emergency treatment appropriately, the traveller should be provided with
written instructions which include seeking urgent medical attention if fever (38°C or more) develops 7 days (or more) after arriving in a malarious area and that self-treatment is indicated if medical help is not available within 24 hours of fever onset.
should you use the same drug that was used for chemoprophylaxis for emergency standby treatment
A drug used for chemoprophylaxis should not be considered for standby treatment for the same traveller due to concerns over drug resistance and to minimise drug toxicity.
Travellers planning journeys across continents can travel into areas that have different malaria prophylaxis recommendations. The choice of prophylaxis medication must …
reflect overall risk to ensure protection in all areas; it may be possible to change from one regimen to another.
important info regarding settles immigrants or long term visitors in the UK
Settled immigrants (or long-term visitors) in the UK may be unaware that any immunity they may have acquired while living in malarious areas is lost rapidly after migration to the UK, or that any non-malarious areas where they lived previously may now be malarious.
chloroquine has a severe interaction with the following antibiotic drug call. what is the interaction and what is it classed as?
macrolides - severe interaction, MHRA says caution.
Azithromycin, clarithromcyin, erythromycin. might increase the risk of serious CV adverse effects when given with chloroquine?
A patient wants some malaria tablets before he goes away next week. you look at his PMR and see that he is taking takes azithromycin three times a week for COPD prophylaxis. from this information which anti-malarial would you ideally want to avoid and why?
ideally avoid chloroquine because A + C = increased risk of CV events including angina, chest pain and HF and mortality.
chloroquine is associated with ocular toxicity. this is unlikely if the dose of chloroquine phosphate does not exceed ….
4mg/kg daily
MHRA advice on hydroxychloroquine, chloroquine - increase risk of CV events when used with this abx class, and reminder of psychiatric reactions
- study found co-admin of azith + hydroxychloroquine in pt with RA was associated with increased risk of CV events (incl angina, chest pain, HF) and mortality
- chloroquine has a similar safety profile to HC - if it cannot be avoided, caution in pt with RF for cardiac events & seek urgent medical attention if any signs of symptoms develop
- also psychiatric reactions associated with chloroquine (typically within 1st month of treatment), including in pt with no Hx psychiatric disorders
chloroquine is …toxic so there is increased risk of …toxicity with drugs e.g.
ototoxic
ototoxicity risk with loop diuretics, aminoglycosides, vincristine vinblastine etc
important side effect of mefloquine and which patients it is contraindicated in
- potentially serious neuropsychiatric reactions
- common: abnormal dreams, insomnia, anxiety, depression
- psychiatric symptoms should be regarded as potentially prodromal for a more serious event
- adverse reactions may occur and persist up to several months after discontinuation due to Long half life
- avoid for prophylaxis if Hx psychiatric disorders (including depression) or convulsions
a patient needs some anti malarial tabs for prophylaxis. she takes sertraline 100mg daily. she is contraindicated for this drug because…
mefloquine contraindicated for prophylaxis if Hx psychotic disorders including depression
it is associated with potentially serious neuropsychiatric reactions
long half life so can persist up to several months after discontinuation
mefloquine - family of quinine so it has this important interaction with drugs
increased risk of QT prolongation with amiodarone, antipsychotics, dronedarone, fluconazole, erythromycin, methadone, etc
a patient is taking atovaquone with proguanil for prophylaxis of malaria. they develop diarrhoea and vomitting. what does this mean.
caution in diarrhoea or vomiting as reduced absorption of A
stop prophylaxis one week after leaving area with this anti-malarial, with all others stop after 4 weeks
atovaquone with proguanil
how long before travel into endemic area should prophylaxis with chloroquine be started
1 week
how long before travel into endemic area should prophylaxis with mefloquine be started
2-3 weeks
how long before travel into endemic area should prophylaxis with atovaquone with proguanil hydrochloride be started
1-2 days
how long before travel into endemic area should prophylaxis with doxycyline hydrochloride be started
1-2 days
prophylaxis with the following 2 should be started 1-2 days before travelling into endemic area
doxycycline
atovaquone with proguanil
who needs to be involved in the treatment of suspected malaria
Expert advice must be sought in all patients suspected to have malaria.
If malaria is diagnosed in a returned traveller, what should you advice other members of the family or travelling group
they may have shared the same exposure risk and they should seek medical attention if they develop symptoms.
If the infective species is not known, or if the infection is mixed and includes falciparum parasites, initial treatment should be as for
falciparum malaria.
Falciparum malaria is caused by which species
Plasmodium falciparum.
malaria is caused by …
parasite
Patients with falciparum malaria should usually be admitted to hospital initially due to
risk of rapid deterioration even after starting treatment.
….. combination therapy is recommended for the treatment of uncomplicated P. falciparum malaria
Artemisinin
these two options can be considered for non-falciparum malaria
Either an artemisinin combination therapy (such as artemether with lumefantrine or artenimol with piperaquine phosphate) or chloroquine
what can be given for non-falciparum malaria treatment throughout pregnancy.
chloroquine
Summarise how many days before travel the following drugs need to be taken
malarone
chloroquine
proguanil
mefloquine
doxycycline
malarone (A+P): 1-2 days
chloroquine: 1 week
proguanil: 1 week
mefloquine: 2-3 weeks
doxycycline: 1-2 days
summarise the dosage for the following
malarone
chloroquine
proguanil
mefloquine
doxycycline
malarone (A+P): 1 daily
chloroquine: 1 weekly
proguanil: 1 daily
mefloquine: 1 weekly
doxycycline: 1 daily
which ones have dosage of one weekly
which ones have dosage of one daily
one weekly: chloroquine + mefloquine
one daily: A+P, Proguanil, doxycycline
summarise how long after travel the following need to be taken for
malarone
chloroquine
proguanil
mefloquine
doxycycline
malarone: 1 week
the rest: 4 weeks
which ones can be used long term
way to remember: PC LONG
progunail (now taken off the market)
chloroquine
max use for malarone, mefloquine, doxycycline
malarone 1 yr
mefloquine 1 yr
doxycycline 2 yrs
Patient is travelling to an area high risk malaria. The doctor has prescribed chloroquine for prophylaxis. This is his PMR: warfarin 3mg, warfarin 1mg, paracetamol 500mg tablets, atorvastatin 20mg, metformin 500mg, gliclazide 80mg. When should he start taking the prophylaxis tablets?
- 1-2 days before - 2-3 weeks before - 1 week before
2-3 weeks before because he is on warfarin. Otherwise, chloroquine is taken 1 week before travel.
which one requires reduced dose in RI
proguanil
patient is on this antimalarial med and has stated that their vision has changed. which drug is it?
chloroquine ototoxic - refer if symptoms
which one needs to be avoided in Hx psychiatric disorders
mefloquine
a couple has come in to the surgery for some anti malarial tabs because they will be staying in liberia for 3 years. which one is appropriate for 3 years use?
malarone
chlorouqine
atovaquone
mefloquine
doxycyline
answer: chloroquine
PC LONG (proguanil and chloroquine) are safe for long term treatment
proguanil has been discontinued in the uk. therefore, the only other one you should use in pregnancy ideally is
chloroquine
