Malaria

Malaria is a very serious and potentially fatal disease caused by a parasite that invades human-feeding mosquito. Common symptoms include fever, excretion problems, headaches and muscle aches and pains.

ABCD of Malaria Prevention

A – Awareness of the Risk

What causes malaria and how common is malaria infection?

Malaria is caused by a type of Plasmodium parasite that infects red blood cells, with the parasite being transmitted by the Anopheles mosquito.

According to the World Health Organisation:

Over 250 million cases have been reported yearly in 2022 with an estimated 600,000 deaths
95% of cases and deaths are reported in Africa
2/3 of this total are in children under 5 years old

Can it affect British travellers?

In 2019, there were 1,719 cases of malaria imported into UK with 15 deaths. However, there is a huge issue of underrepresentation, with a PHS report citing only 56% of cases have been captured
85.8% of these cases came from Plasmidium falciparum
87% of people who had died had not taken chemoprophylaxis

Pre-COVID, malaria has been on the rise with cases above the mean in 6 of the last 7 years.
Image taken from https://www.gov.uk/government/publications/malaria-in-the-uk-annual-report/malaria-imported-into-the-uk-2021.

UK travellers at the highest risk of infection

Decide not to take, takes incorrect or does not complete antimalerial medication
Unaware of malaria risk so do not seek advice from trained professionals

Risk factors one must consider when making their risk assessment for malaria

Temperature, altitude and season
Rural versus urban location
Type of accommodation
Length of stay
Drug resistant P. falciparum strains

B – Bite Prevention

The most effective way to prevent malaria infection is by not allowing mosquito biting.

A prevalent way of achieving this is can be through the use of insect repellant:

DEET is an insect repelant and is strongly recommended by Malaria guidelines (2021)
Also known as N,N-diethyl-m-toluamide and has been used as insect repellant for over 60 years
Longest protection length of any repellant (needs reapplying every 2-3 hours in very humid and hot conditions)
Can be used anyone over the age of 2 months
However DEET has negative effects after excessive use and some people are allergic. Negative effects include seizures, uncoordinated movements, agitation, aggression and skin irritation
Alternative, less invasive options include: Picaridin/Icaridin and Eucalyptus
Citrodora

Other bite avoidance methods include:

Mosquito nets; prevents mosquitoes entering or biting through, long lasting nets last 3-5 years
Minimising accessibility to skin; this invludes wearing loose fitting, long-sleeves and trousers, even more effective if DEET or permethrin is impregnated on the outside
Room protection; Use air conditioning, fans, mesh door, knockdown spray, plugin vaporisers and mosquito coils

More information on bite avoidance can be found on the government website.

C – Chemoprophylaxis

Chemoprophylaxis is the administration of a medication for the purpose of preventing incidence of disease

Medication is taken before, during and after the trip to kill malaria parasites if contracted whilst away

Main medication options:

Doxycycline – an antibiotic used to treat chest, dental and skin infections
Lariam – A specific anti-malaria medicine often taken as a tablet to prevent Plasmodium replication in the red blood cells
Atovaquone & Proguanil – antimalarial mediciations that kill the Plasmodium parasites
Chloroquine – builds up toxic substances within the parasite, eventually leading to their death

How to decide which malaria medication to administer:

Potential risks (side effects)
Drug availability
You must discuss pros and cons of suitable medications to help the patient make an informed decision

Medication Profiles

Doxycycline:

Course: 1 capsule daily starting 1-2 days before, every day
during trip and 4 weeks after
How to be safe taking it: take with food, plenty of
water, upright 30 minutes, limit sun exposure, thrush
Who can not take the medication: child under 12, pregnancy*,
breastfeeding, allergy to tetracycline
*Do not take with oral typhoid tablets*

Mefloquine (lariam):

Course: Weekly tablet, starting 2-3 weeks before, weekly
during trip and 4 weeks after, *3-week trial recommended first time*
How to be safe taking it: Requires careful risk assessment due to possible
neuropsychiatric problems
Who can not take the medication: current or previous history of
depression, neuropsychiatric disorders, epilepsy and those with heart issues
Possible side effects: nightmares, insomnia, anxiety,
depressed mood, confusion.
*Do not prescribe to pilots or scuba divers*

Atovaquone & Proguanil:

1 tablet daily, starting 1-2 days before, every day during trip and 7 days after
Who can not take the medication: Those on HIV medication, tetracyclines and metoclopramide
Common side effects: headaches, GI upset. Occasionally abnormal dreams

Long term use:

When to administer medication

Always use a malaria map to make an informed decision on when to administer medication

There is risk of P.falciparum and P. vivax infection at all times of the year, however in many regions the risk is so low that it should only be administered to those of high risk i.e. >70 years old, long term travellers visiting friendsfamily, immunosuppressed, pregnant women and young children.
When someone is at too much risk i.e. poor splenic function or completely immunocompromised, travel should be strongly advised against.
In high risk areas atovaquone/proguanil OR doxycycline OR mefloquine is advised
In low risk areas atovaquone/proguanil OR doxycycline OR mefloquine is advised only for those at high risk
In low to no risk areas medications are not advised due to potential adverse effects
*Always check dosage before administration*

D – Diagnosis and Treatment

SUSPECTED MALARIA IS A MEDICAL EMERGENCY
Patients must report any flu like symptoms promptly and must inform clinician of their travel
to a malarial area
Symptoms: Can be non-specific and ‘flu-like. They also commonly do not appear until at least 8 days after arrival into the malarial region
Malaria can only be confirmed via a blood test

Complex Cases

Complex cases when dealing with malaria infection include those who are pregnant, young children and have Sickle Cell Anaemia

For those who are pregnant you must ask:

Is the trip necessary?
What trimester is the mother currently on?
Are their ante-natal notes easily accessible?

Medications in Pregancy:

Mefloquine is the first choice but risk assessments are vital
Doxycycline can also be used up to 15 weeks gestation
A&P should ideally be avoided in pregnancy but can be used in 2nd & 3rd trimesters if no alternative available.
Needs 5mg Folate supplement

Child Travellers:

Children are especially viable to Malaria through not taking precautions to avoid infection
When prescribing drugs, children must be weighed to ensure correct dosage is given
Exact dose will be provided on the manufacturers website

Sickle Cell Anaemic:

SCA confers a level of protection against maleria, but NEVERTHELESS, patients still require chemophrophylaxis

Useful Recourses about Malaria

Large areas of Africa and South Asia and parts of Central and South America, the Caribbean, Southeast Asia, the Middle East, and Oceania
Databases like NaTHNaC have interactive searchable malaria maps and general information for countries with a risk of malaria infection

*Always check malaria maps when patients are travelling to at risk countries*

Travax has an in depth document describing the malaria risk level to travellers
UK HSA also has a useful document outlining how to prevent malaria whilst travelling

Further information on malaria: